CN115703853B - Supported double-center catalyst and preparation method and application thereof - Google Patents
Supported double-center catalyst and preparation method and application thereof Download PDFInfo
- Publication number
- CN115703853B CN115703853B CN202110895080.1A CN202110895080A CN115703853B CN 115703853 B CN115703853 B CN 115703853B CN 202110895080 A CN202110895080 A CN 202110895080A CN 115703853 B CN115703853 B CN 115703853B
- Authority
- CN
- China
- Prior art keywords
- catalyst
- hours
- temperature
- drying
- vanadium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 212
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 238000006243 chemical reaction Methods 0.000 claims abstract description 132
- 239000011651 chromium Substances 0.000 claims abstract description 123
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 78
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 76
- -1 aluminum compound Chemical class 0.000 claims abstract description 70
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 70
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 63
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims abstract description 59
- 238000007654 immersion Methods 0.000 claims abstract description 43
- 239000003607 modifier Substances 0.000 claims abstract description 33
- 238000011068 loading method Methods 0.000 claims abstract description 32
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 21
- 239000002243 precursor Substances 0.000 claims abstract description 12
- 238000005470 impregnation Methods 0.000 claims description 69
- 238000010438 heat treatment Methods 0.000 claims description 63
- 238000000034 method Methods 0.000 claims description 51
- 239000011148 porous material Substances 0.000 claims description 50
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 30
- 230000008569 process Effects 0.000 claims description 21
- 238000001354 calcination Methods 0.000 claims description 15
- 150000001336 alkenes Chemical class 0.000 claims description 13
- 229910052751 metal Inorganic materials 0.000 claims description 12
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 11
- 125000005287 vanadyl group Chemical group 0.000 claims description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 230000003213 activating effect Effects 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 6
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 6
- 150000004820 halides Chemical class 0.000 claims description 6
- YBYIRNPNPLQARY-UHFFFAOYSA-N 1H-indene Natural products C1=CC=C2CC=CC2=C1 YBYIRNPNPLQARY-UHFFFAOYSA-N 0.000 claims description 5
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 5
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 5
- 125000000217 alkyl group Chemical group 0.000 claims description 5
- 125000004432 carbon atom Chemical group C* 0.000 claims description 5
- 125000000058 cyclopentadienyl group Chemical group C1(=CC=CC1)* 0.000 claims description 5
- ZSWFCLXCOIISFI-UHFFFAOYSA-N endo-cyclopentadiene Natural products C1C=CC=C1 ZSWFCLXCOIISFI-UHFFFAOYSA-N 0.000 claims description 5
- 125000003983 fluorenyl group Chemical group C1(=CC=CC=2C3=CC=CC=C3CC12)* 0.000 claims description 5
- 125000003454 indenyl group Chemical group C1(C=CC2=CC=CC=C12)* 0.000 claims description 5
- ZOYIPGHJSALYPY-UHFFFAOYSA-K vanadium(iii) bromide Chemical compound [V+3].[Br-].[Br-].[Br-] ZOYIPGHJSALYPY-UHFFFAOYSA-K 0.000 claims description 5
- 229910021552 Vanadium(IV) chloride Inorganic materials 0.000 claims description 4
- 239000004927 clay Substances 0.000 claims description 4
- JTJFQBNJBPPZRI-UHFFFAOYSA-J vanadium tetrachloride Chemical compound Cl[V](Cl)(Cl)Cl JTJFQBNJBPPZRI-UHFFFAOYSA-J 0.000 claims description 4
- VJNMUKGZDONIAN-UHFFFAOYSA-N 1-methylisoquinolin-6-amine Chemical compound NC1=CC=C2C(C)=NC=CC2=C1 VJNMUKGZDONIAN-UHFFFAOYSA-N 0.000 claims description 3
- 101150039077 CRCP gene Proteins 0.000 claims description 3
- 229910021551 Vanadium(III) chloride Inorganic materials 0.000 claims description 3
- 150000004703 alkoxides Chemical class 0.000 claims description 3
- 229910000323 aluminium silicate Inorganic materials 0.000 claims description 3
- 229910052570 clay Inorganic materials 0.000 claims description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims description 3
- 229910052736 halogen Inorganic materials 0.000 claims description 3
- 239000000395 magnesium oxide Substances 0.000 claims description 3
- QLOKAVKWGPPUCM-UHFFFAOYSA-N oxovanadium;dihydrochloride Chemical compound Cl.Cl.[V]=O QLOKAVKWGPPUCM-UHFFFAOYSA-N 0.000 claims description 3
- 239000000377 silicon dioxide Substances 0.000 claims description 3
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 3
- 229910001887 tin oxide Inorganic materials 0.000 claims description 3
- JTWLHYPUICYOLE-UHFFFAOYSA-J vanadium tetrafluoride Chemical compound [F-].[F-].[F-].[F-].[V+4] JTWLHYPUICYOLE-UHFFFAOYSA-J 0.000 claims description 3
- HQYCOEXWFMFWLR-UHFFFAOYSA-K vanadium(iii) chloride Chemical compound [Cl-].[Cl-].[Cl-].[V+3] HQYCOEXWFMFWLR-UHFFFAOYSA-K 0.000 claims description 3
- 239000011787 zinc oxide Substances 0.000 claims description 3
- CMAOLVNGLTWICC-UHFFFAOYSA-N 2-fluoro-5-methylbenzonitrile Chemical compound CC1=CC=C(F)C(C#N)=C1 CMAOLVNGLTWICC-UHFFFAOYSA-N 0.000 claims description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 2
- 230000000379 polymerizing effect Effects 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims 1
- 125000005843 halogen group Chemical group 0.000 claims 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 abstract description 83
- 239000005977 Ethylene Substances 0.000 abstract description 83
- 229920000642 polymer Polymers 0.000 abstract description 37
- 238000009826 distribution Methods 0.000 abstract description 23
- 230000002902 bimodal effect Effects 0.000 abstract description 11
- 238000007334 copolymerization reaction Methods 0.000 abstract description 11
- 230000037048 polymerization activity Effects 0.000 abstract description 11
- 239000001257 hydrogen Substances 0.000 abstract description 8
- 229910052739 hydrogen Inorganic materials 0.000 abstract description 8
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 abstract description 7
- 230000035945 sensitivity Effects 0.000 abstract description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 192
- 238000001035 drying Methods 0.000 description 182
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 162
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 147
- 239000000243 solution Substances 0.000 description 98
- 229910052757 nitrogen Inorganic materials 0.000 description 96
- 239000002904 solvent Substances 0.000 description 70
- 239000012018 catalyst precursor Substances 0.000 description 67
- 238000010992 reflux Methods 0.000 description 59
- MCULRUJILOGHCJ-UHFFFAOYSA-N triisobutylaluminium Chemical compound CC(C)C[Al](CC(C)C)CC(C)C MCULRUJILOGHCJ-UHFFFAOYSA-N 0.000 description 46
- 239000011261 inert gas Substances 0.000 description 39
- 238000004321 preservation Methods 0.000 description 33
- 238000003756 stirring Methods 0.000 description 31
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 30
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 30
- 238000003860 storage Methods 0.000 description 30
- 238000005406 washing Methods 0.000 description 30
- 239000000725 suspension Substances 0.000 description 28
- 229910004298 SiO 2 Inorganic materials 0.000 description 27
- 230000004913 activation Effects 0.000 description 24
- 230000003197 catalytic effect Effects 0.000 description 21
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 20
- 239000004698 Polyethylene Substances 0.000 description 19
- 229920000573 polyethylene Polymers 0.000 description 19
- 238000001816 cooling Methods 0.000 description 18
- 238000002474 experimental method Methods 0.000 description 18
- 239000000178 monomer Substances 0.000 description 18
- 230000000052 comparative effect Effects 0.000 description 17
- 230000018044 dehydration Effects 0.000 description 16
- 238000006297 dehydration reaction Methods 0.000 description 16
- 230000000694 effects Effects 0.000 description 16
- 230000001105 regulatory effect Effects 0.000 description 16
- 238000011049 filling Methods 0.000 description 15
- 239000012535 impurity Substances 0.000 description 15
- 239000011259 mixed solution Substances 0.000 description 15
- 239000003960 organic solvent Substances 0.000 description 15
- 125000005234 alkyl aluminium group Chemical group 0.000 description 14
- 239000012298 atmosphere Substances 0.000 description 14
- 238000007599 discharging Methods 0.000 description 14
- 238000001914 filtration Methods 0.000 description 14
- 238000005086 pumping Methods 0.000 description 14
- 229910001220 stainless steel Inorganic materials 0.000 description 14
- 239000010935 stainless steel Substances 0.000 description 14
- 239000004711 α-olefin Substances 0.000 description 13
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 12
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 12
- 230000009467 reduction Effects 0.000 description 12
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 11
- VOITXYVAKOUIBA-UHFFFAOYSA-N triethylaluminium Chemical compound CC[Al](CC)CC VOITXYVAKOUIBA-UHFFFAOYSA-N 0.000 description 11
- LIKMAJRDDDTEIG-UHFFFAOYSA-N 1-hexene Chemical compound CCCCC=C LIKMAJRDDDTEIG-UHFFFAOYSA-N 0.000 description 10
- 229910052786 argon Inorganic materials 0.000 description 10
- 239000001307 helium Substances 0.000 description 9
- 229910052734 helium Inorganic materials 0.000 description 9
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 9
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 8
- AFABGHUZZDYHJO-UHFFFAOYSA-N dimethyl butane Natural products CCCC(C)C AFABGHUZZDYHJO-UHFFFAOYSA-N 0.000 description 8
- QWTDNUCVQCZILF-UHFFFAOYSA-N isopentane Chemical compound CCC(C)C QWTDNUCVQCZILF-UHFFFAOYSA-N 0.000 description 8
- 239000003446 ligand Substances 0.000 description 7
- CPOFMOWDMVWCLF-UHFFFAOYSA-N methyl(oxo)alumane Chemical compound C[Al]=O CPOFMOWDMVWCLF-UHFFFAOYSA-N 0.000 description 7
- 230000002194 synthesizing effect Effects 0.000 description 7
- VXNZUUAINFGPBY-UHFFFAOYSA-N 1-Butene Chemical compound CCC=C VXNZUUAINFGPBY-UHFFFAOYSA-N 0.000 description 6
- KWKAKUADMBZCLK-UHFFFAOYSA-N 1-octene Chemical compound CCCCCCC=C KWKAKUADMBZCLK-UHFFFAOYSA-N 0.000 description 6
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 6
- 239000012190 activator Substances 0.000 description 6
- 238000003780 insertion Methods 0.000 description 6
- 230000037431 insertion Effects 0.000 description 6
- YNLAOSYQHBDIKW-UHFFFAOYSA-M diethylaluminium chloride Chemical compound CC[Al](Cl)CC YNLAOSYQHBDIKW-UHFFFAOYSA-M 0.000 description 5
- 230000009977 dual effect Effects 0.000 description 5
- 229920001519 homopolymer Polymers 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 230000035484 reaction time Effects 0.000 description 5
- OFBQJSOFQDEBGM-UHFFFAOYSA-N Pentane Chemical compound CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 4
- TYYBBNOTQFVVKN-UHFFFAOYSA-N chromium(2+);cyclopenta-1,3-diene Chemical compound [Cr+2].C=1C=C[CH-]C=1.C=1C=C[CH-]C=1 TYYBBNOTQFVVKN-UHFFFAOYSA-N 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 238000007598 dipping method Methods 0.000 description 4
- 239000011363 dried mixture Substances 0.000 description 4
- NNPPMTNAJDCUHE-UHFFFAOYSA-N isobutane Chemical compound CC(C)C NNPPMTNAJDCUHE-UHFFFAOYSA-N 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 239000012299 nitrogen atmosphere Substances 0.000 description 4
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical class [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 4
- PBKONEOXTCPAFI-UHFFFAOYSA-N 1,2,4-trichlorobenzene Chemical compound ClC1=CC=C(Cl)C(Cl)=C1 PBKONEOXTCPAFI-UHFFFAOYSA-N 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 239000003153 chemical reaction reagent Substances 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 229910052801 chlorine Inorganic materials 0.000 description 3
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 3
- 238000005227 gel permeation chromatography Methods 0.000 description 3
- 230000001976 improved effect Effects 0.000 description 3
- 238000011065 in-situ storage Methods 0.000 description 3
- 125000002524 organometallic group Chemical group 0.000 description 3
- 239000002685 polymerization catalyst Substances 0.000 description 3
- 230000000630 rising effect Effects 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 230000002195 synergetic effect Effects 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 229910052719 titanium Inorganic materials 0.000 description 3
- 239000008096 xylene Substances 0.000 description 3
- ZGEGCLOFRBLKSE-UHFFFAOYSA-N 1-Heptene Chemical compound CCCCCC=C ZGEGCLOFRBLKSE-UHFFFAOYSA-N 0.000 description 2
- AFFLGGQVNFXPEV-UHFFFAOYSA-N 1-decene Chemical compound CCCCCCCCC=C AFFLGGQVNFXPEV-UHFFFAOYSA-N 0.000 description 2
- CRSBERNSMYQZNG-UHFFFAOYSA-N 1-dodecene Chemical compound CCCCCCCCCCC=C CRSBERNSMYQZNG-UHFFFAOYSA-N 0.000 description 2
- OEOUWMSQXZQDIP-UHFFFAOYSA-N CC[Al](CC)CC.CC1=CC=CC=C1 Chemical compound CC[Al](CC)CC.CC1=CC=CC=C1 OEOUWMSQXZQDIP-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- 229920000089 Cyclic olefin copolymer Polymers 0.000 description 2
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- 239000007825 activation reagent Substances 0.000 description 2
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000003426 co-catalyst Substances 0.000 description 2
- 229920001577 copolymer Polymers 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- GCPCLEKQVMKXJM-UHFFFAOYSA-N ethoxy(diethyl)alumane Chemical compound CCO[Al](CC)CC GCPCLEKQVMKXJM-UHFFFAOYSA-N 0.000 description 2
- 229920001038 ethylene copolymer Polymers 0.000 description 2
- 150000002367 halogens Chemical group 0.000 description 2
- 239000001282 iso-butane Substances 0.000 description 2
- 239000012968 metallocene catalyst Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- CRSOQBOWXPBRES-UHFFFAOYSA-N neopentane Chemical compound CC(C)(C)C CRSOQBOWXPBRES-UHFFFAOYSA-N 0.000 description 2
- HHQFLEDKAVLHOM-UHFFFAOYSA-N oxovanadium;trihydrofluoride Chemical compound F.F.F.[V]=O HHQFLEDKAVLHOM-UHFFFAOYSA-N 0.000 description 2
- YWAKXRMUMFPDSH-UHFFFAOYSA-N pentene Chemical compound CCCC=C YWAKXRMUMFPDSH-UHFFFAOYSA-N 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 2
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 229910002027 silica gel Inorganic materials 0.000 description 2
- 239000000741 silica gel Substances 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 230000008093 supporting effect Effects 0.000 description 2
- JLTRXTDYQLMHGR-UHFFFAOYSA-N trimethylaluminium Chemical compound C[Al](C)C JLTRXTDYQLMHGR-UHFFFAOYSA-N 0.000 description 2
- OCJBOOLMMGQPQU-UHFFFAOYSA-N 1,4-dichlorobenzene Chemical class ClC1=CC=C(Cl)C=C1 OCJBOOLMMGQPQU-UHFFFAOYSA-N 0.000 description 1
- WWUVJRULCWHUSA-UHFFFAOYSA-N 2MP Natural products CCCC(C)=C WWUVJRULCWHUSA-UHFFFAOYSA-N 0.000 description 1
- SUWJESCICIOQHO-UHFFFAOYSA-N 4-methylhex-1-ene Chemical compound CCC(C)CC=C SUWJESCICIOQHO-UHFFFAOYSA-N 0.000 description 1
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- 238000005481 NMR spectroscopy Methods 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 229910021550 Vanadium Chloride Inorganic materials 0.000 description 1
- WFISYBKOIKMYLZ-UHFFFAOYSA-N [V].[Cr] Chemical compound [V].[Cr] WFISYBKOIKMYLZ-UHFFFAOYSA-N 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 150000001335 aliphatic alkanes Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- UNTBPXHCXVWYOI-UHFFFAOYSA-O azanium;oxido(dioxo)vanadium Chemical compound [NH4+].[O-][V](=O)=O UNTBPXHCXVWYOI-UHFFFAOYSA-O 0.000 description 1
- 238000000071 blow moulding Methods 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 238000012662 bulk polymerization Methods 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000012986 chain transfer agent Substances 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- ZHXZNKNQUHUIGN-UHFFFAOYSA-N chloro hypochlorite;vanadium Chemical compound [V].ClOCl ZHXZNKNQUHUIGN-UHFFFAOYSA-N 0.000 description 1
- 150000001844 chromium Chemical class 0.000 description 1
- ILSAAZMXLRJGAP-UHFFFAOYSA-N chromium cyclopenta-1,3-diene Chemical compound [Cr].C1C=CC=C1.C1C=CC=C1 ILSAAZMXLRJGAP-UHFFFAOYSA-N 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- GUJOJGAPFQRJSV-UHFFFAOYSA-N dialuminum;dioxosilane;oxygen(2-);hydrate Chemical compound O.[O-2].[O-2].[O-2].[Al+3].[Al+3].O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O GUJOJGAPFQRJSV-UHFFFAOYSA-N 0.000 description 1
- 238000005906 dihydroxylation reaction Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 229940069096 dodecene Drugs 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 238000010528 free radical solution polymerization reaction Methods 0.000 description 1
- 238000012685 gas phase polymerization Methods 0.000 description 1
- 239000000499 gel Substances 0.000 description 1
- RYPKRALMXUUNKS-UHFFFAOYSA-N hex-2-ene Chemical compound CCCC=CC RYPKRALMXUUNKS-UHFFFAOYSA-N 0.000 description 1
- 229920001903 high density polyethylene Polymers 0.000 description 1
- 238000004742 high temperature nuclear magnetic resonance Methods 0.000 description 1
- 239000004700 high-density polyethylene Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000010952 in-situ formation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 description 1
- 125000000959 isobutyl group Chemical group [H]C([H])([H])C([H])(C([H])([H])[H])C([H])([H])* 0.000 description 1
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 229920002521 macromolecule Polymers 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 229910052901 montmorillonite Inorganic materials 0.000 description 1
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical compound CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 1
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 125000003136 n-heptyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 125000001280 n-hexyl group Chemical group C(CCCCC)* 0.000 description 1
- 125000000740 n-pentyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 125000004123 n-propyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 1
- 229920006280 packaging film Polymers 0.000 description 1
- 239000012785 packaging film Substances 0.000 description 1
- RPESBQCJGHJMTK-UHFFFAOYSA-I pentachlorovanadium Chemical compound [Cl-].[Cl-].[Cl-].[Cl-].[Cl-].[V+5] RPESBQCJGHJMTK-UHFFFAOYSA-I 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000010557 suspension polymerization reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000006276 transfer reaction Methods 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
- 229910001928 zirconium oxide Inorganic materials 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
Abstract
The invention discloses a supported double-center catalyst and a preparation method and application thereof, wherein the supported double-center catalyst comprises a carrier and active components, and the preparation method comprises the following steps: step 1, immersing a carrier in a modifier solution for an immersion reaction, wherein the modifier solution comprises a modifier, and the modifier is an organic aluminum compound; and 2, loading the precursor of the active component on the modified carrier, wherein the precursor of the active component comprises an organic chromium source and an inorganic vanadium source, so as to obtain the supported double-center catalyst. The catalyst has the characteristics of high polymerization activity, excellent hydrogen regulation sensitivity and good copolymerization performance, and can be applied to the existing single-kettle ethylene polymerization process to prepare polymer products with wide molecular weight distribution and bimodal distribution.
Description
Technical Field
The invention belongs to the field of catalysts, and particularly relates to a supported vanadium-chromium double-center catalyst, and a preparation method and application thereof.
Background
Polyethylene has excellent mechanical properties and processability and is widely used in various fields of national life, such as food packaging films, blow molding containers, agricultural films, water supply and drainage pipelines, automobile parts, electronic devices and the like. The consumption of polyethylene is also increasing year by year, and the annual output of the polyethylene breaks through 1 hundred million tons at present, so that the development of a new catalytic technology for synthesizing the polyethylene has important significance.
Currently, catalysts for synthesizing polyethylene, which are widely used in industry, mainly comprise three major categories: ziegler-Natta titanium based catalysts, chromium-based catalysts (mainly comprising inorganic chromium Phillip catalysts and organic chromium S-2 catalysts) and metallocene catalysts. The general characteristics of the above-mentioned catalyst polyethylene products are that the molecular weight is unimodal and that the distribution of short chain branches in the ethylene/alpha-olefin copolymer generally tends to be concentrated and the low molecular weight fraction (the product obtained with metallocene catalysts is substantially uniformly distributed along the molecular weight). However, the results of the physical research on the polymer show that compared with the unimodal polyethylene, the polyethylene product with wide and bimodal molecular weight distribution has better mechanical properties and excellent processability. In addition, the introduction of a small amount of short-chain branches into the high molecular weight component of the polyethylene can also obviously improve the long-term mechanical properties of the product, such as the slow crack growth (Krishnaswamy,R.K.;Yang,Q.;Fernandez-Ballester,L.;Kornfield,J.A.Effect of the Distribution of Short-Chain Branches on Crystallization Kinetics and Mechanical Properties of High-Density Polyethylene.Macromolecules.2008,41,1693-1704.). resistance for synthesizing the bimodal polyethylene with excellent short-chain branches distributed in the high molecular weight component, currently, two or more reaction kettles are commonly used in industry for series operation, and the preparation method is realized by regulating and controlling the concentration of chain transfer agent and comonomer of each reaction kettle. But obviously the equipment investment and operating costs of the process are increased.
At the same time, industry and academia are actively exploring new, more green and low cost production processes. More reports are reported therein to develop a composite double-center catalyst, namely, two catalysts are blended or co-supported on a certain carrier, and the research starting point is that the catalyst can have the characteristics of two active centers at the same time, and even shows more excellent catalytic characteristics by utilizing the synergistic effect between the two active centers. The bimetallic center polyethylene catalyst (CN 103626899A and CN 104448067A) has excellent catalytic synergistic effect under most conditions, so that the polymerization activity, copolymerization performance and the like of the catalyst are obviously improved on the basis of the original single-metal catalyst, the molecular weight of the synthesized polymer is distributed in a broad peak or a double peak, and the comonomer is also intensively distributed in a high molecular weight component, so that the series of catalysts has great advantages in the aspect of synthesizing the high-performance bimodal polyethylene by a single-kettle method, and the series of catalysts are likely to partially replace the double-kettle serial connection process for synthesizing the high-performance bimodal polyethylene material commonly used in industry because the equipment investment for synthesizing the high-performance bimodal polyethylene in a single reaction kettle by utilizing the double-center catalytic technology is lower, the operation difficulty is lower and the energy consumption is lower compared with the latter.
Disclosure of Invention
The invention mainly aims to provide a supported double-center catalyst and a preparation method and application thereof, so as to overcome the defects of low polymerization activity and low comonomer insertion rate of the double-center catalyst in the prior art.
In order to achieve the above object, the present invention provides a method for preparing a supported double-center catalyst comprising a carrier and an active component, the method comprising the steps of:
Step 1, immersing a carrier in a modifier solution for an immersion reaction, wherein the modifier solution comprises a modifier, and the modifier is an organic aluminum compound;
And2, loading the precursor of the active component on the modified carrier, wherein the precursor of the active component comprises an organic chromium source and an inorganic vanadium source, so as to obtain the supported double-center catalyst.
The preparation method of the supported double-center catalyst provided by the invention comprises the step of roasting the carrier before dipping the modifier solution so as to remove water and part of hydroxyl on the surface of the carrier.
The preparation method of the supported double-center catalyst comprises the steps of carrying an organic chromium source and an inorganic vanadium source in steps or carrying the organic chromium source and the inorganic vanadium source simultaneously.
The preparation method of the supported double-center catalyst comprises the steps of roasting at 200-900 ℃, wherein the temperature rising rate in the roasting process is 0.1-10 ℃/min, and the roasting time is 1-10 h; the loading method of step 2 is impregnation.
The invention relates to a preparation method of a supported double-center catalyst, wherein the carrier is at least one of silicon oxide, aluminum oxide, aluminosilicate, inorganic clay, titanium oxide, zirconium oxide, magnesium oxide, ferric oxide, tin oxide and zinc oxide; the specific surface area of the carrier is 100-1000 m 2/g, the pore volume is 0.3-5.0 cm 3/g, and the average pore diameter is 5-50 nm.
The preparation method of the supported double-center catalyst comprises the step of preparing an organic aluminum compound from at least one of trialkylaluminum AlR 3, dialkylaluminum alkoxide AlR 2 OR, dialkylaluminum halide AlR 2 X, aluminoxane and ethyl sesquialuminum chloride, wherein R is an alkyl group with 1-12 carbon atoms, and X is halogen.
The invention relates to a preparation method of a supported double-center catalyst, wherein the organic chromium source contains at least one of cyclopentadienyl ligand, indenyl ligand and fluorenyl ligand; the inorganic vanadium source is a vanadium-containing halide.
The invention relates to a preparation method of a supported double-center catalyst, wherein the structural formula of an organic chromium source is as follows: crCp 1Cp2, wherein Cp 1 and Cp 2 are independently one of cyclopentadienyl, indenyl and fluorenyl, and Cp 1 is the same or different from Cp 2; the vanadium source is at least one selected from vanadium trifluoride, vanadium trichloride, vanadium tribromide, vanadium tetrafluoride, vanadium tetrachloride, vanadyl difluoride, vanadyl dichloride, vanadyl dibromide, vanadyl trifluoride and vanadyl trichloride.
In order to achieve the above purpose, the present invention also provides a supported double-center catalyst, which is prepared by the preparation method of the supported double-center catalyst, wherein the content of Cr is 0.1wt% -8 wt%, the content of V is 0.1wt% -10 wt%, and the content of modifier is 0.1-10 wt% based on the total mass of the supported double-center catalyst.
In order to achieve the above object, the present invention further provides a method for polymerizing olefins, using the supported double-center catalyst.
The olefin polymerization method comprises an activation step of the supported double-center catalyst, wherein an activation reagent is an alkyl aluminum compound.
The invention has the beneficial effects that:
1. The two active centers in the double-active-center catalyst can better represent respective catalytic performance, and also show good catalytic synergistic effect, and meanwhile, the catalytic activity of the catalyst can be further improved by modifying the catalyst carrier;
2. compared with the traditional single-center and double-center catalysts, the bimetallic center catalyst can lead the molecular weight distribution of a polymer to be wider and to be in bimodal distribution when being used for olefin polymerization, comprises a lower molecular weight ethylene homopolymer A synthesized by an organic chromium active center, a higher molecular weight ethylene copolymer B synthesized by an organic vanadium active center, and the relative content of the two components A and B can be mainly adjusted by adjusting the relative content of the two active centers in the catalyst;
3. The two active centers of the bimetallic center catalyst have strong sensitivity to an activated reagent aluminum alkyl compound, namely, a chlorine-containing activated reagent has strong activation effect on a vanadium component, but has weak activation effect on an organic chromium component, and the relative content of an A component and a B component in the polymer can be sensitively regulated and controlled by utilizing the differential reaction of the two chromium components and the vanadium component on a cocatalyst through regulating the activator component;
4. The bimetallic center catalyst carrier is treated by the modifier, so that the copolymerization efficiency of the catalyst can be improved, namely the comonomer insertion rate of the bimetallic center catalyst with the carrier treated by the modifier is higher under the same comonomer addition amount;
Thus, the supported dual site catalysts of the present invention can produce ethylene homopolymers and ethylene/alpha-olefin copolymers having a relatively broad molecular weight distribution, even bimodal distribution, containing lower molecular weight ethylene homopolymers and higher molecular weight copolymers of ethylene and alpha-olefins in a single reactor. The catalyst also has higher ethylene homopolymerization and ethylene and alpha-olefin copolymerization reactivity.
Detailed Description
The following describes the present invention in detail, and the present examples are implemented on the premise of the technical solution of the present invention, and detailed embodiments and processes are given, but the scope of protection of the present invention is not limited to the following examples, in which the experimental methods of specific conditions are not noted, and generally according to conventional conditions.
The invention provides a preparation method of a supported double-center catalyst, which comprises a carrier and active components, and comprises the following steps:
Step 1, immersing a carrier in a modifier solution for an immersion reaction, wherein the modifier solution comprises a modifier, and the modifier is an organic aluminum compound;
And2, loading the precursor of the active component on the modified carrier, wherein the precursor of the active component comprises an organic chromium source and an inorganic vanadium source, so as to obtain the supported double-center catalyst.
In one embodiment, the support further comprises a calcination operation to remove water and a portion of the hydroxyl groups from the support surface prior to impregnating the modifier solution.
The calcination operation may be performed in either a fluidized state or a non-fluidized state, but is preferably performed in a fluidized state. In one embodiment, the calcination operation is performed in an inert atmosphere such as nitrogen or argon to prevent residual oxygen in the support from reacting with the chromium or vanadium source during subsequent processing. The temperature of the calcination may be 200 to 900 ℃, preferably 300 to 600 ℃, the temperature rising rate of the calcination process is 0.1 to 10 ℃/min, preferably 3 to 5 ℃/min, and the calcination time may be 1 to 10 hours, preferably 2 to 4 hours. The hydroxyl density of the carrier surface has double influences on the active components, on one hand, the hydroxyl with the too high density has poisoning effect on the active center, and the hydroxyl with the too low density is unfavorable for the loading of a chromium source and a vanadium source, so the invention can remove part of the hydroxyl by roasting the carrier, and the surface of the catalyst carrier has proper hydroxyl density.
In one embodiment, the carrier of the present invention is a porous inorganic carrier, and may be at least one of silica, alumina, aluminosilicate, inorganic clay, titania, zirconia, magnesia, iron oxide, tin oxide, and zinc oxide; among them, the inorganic clay is preferably montmorillonite, and the silica is preferably amorphous porous silica gel. In another embodiment, the support of the invention has a specific surface area of from 100 to 1000m 2/g, a pore volume of from 0.3 to 5.0cm 3/g and an average pore diameter of from 5 to 50nm.
In one embodiment, the modifier used for the modification of the support is an organoaluminum compound including aluminum alkyls and derivatives thereof such as aluminum trialkyl AlR 3, aluminum dialkylalkoxides AlR 2 OR, aluminum dialkylhalides AlR 2 X, aluminoxane, ethyl silsesquioxane chloride and the like wherein R is an alkyl group such as an alkyl group having 1 to 12 carbon atoms, more such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-dodecyl and the like and X is a halogen such as fluorine, chlorine, bromine and iodine, preferably chlorine. Wherein, the aluminoxane is the reactant of alkyl aluminum and water. The modifier of the present invention may be used alone or in combination of two or more. As a specific example, the modifier may be at least one of triethylaluminum, triisobutylaluminum, diethylaluminum ethoxide, diethylaluminum chloride and methylaluminoxane.
In one embodiment, the step of modifying the support comprises: and (3) placing the carrier after roasting treatment and the modifier organic aluminum compound into an organic solvent for carrying out an impregnation reaction to obtain the modified carrier. The organic solvent in the impregnation process is an inert organic solvent, and the organic aluminum compound enters porous inorganic carrier pore channels through an impregnation stirring method and is adsorbed on the surface of the porous inorganic carrier pore channels. In detail, the organoaluminum compound enters the pores of the carrier to react with hydroxyl groups, and is anchored to the surface of the carrier, and is physically adsorbed to the inner surfaces of the pores of the carrier. Not only can remove partial physical adsorption water and hydroxyl on the surface of the silica gel carrier, but also is beneficial to the interaction between the active components of the catalyst and the organic aluminum compound.
In another embodiment, the inert organic solvent may be at least one of n-hexane, n-heptane, n-octane, benzene, toluene, xylene, etc. The dipping temperature is 20-180 ℃, preferably 45-120 ℃, and the dipping time is 1-24 hours, preferably 4-12 hours; the solvent in the system is evaporated and removed at high temperature after the impregnation is finished to achieve the aim of drying, wherein the drying is performed at 60-150 ℃, preferably at 80-130 ℃, and the drying time is 2-24 hours, preferably 6-16 hours.
In yet another embodiment, the modifier comprises 0.1 to 10wt% of the total weight of the catalyst, calculated as Al.
In one embodiment, the organochromium source of the present invention contains at least one of a cyclopentadienyl ligand, an indenyl ligand, a fluorenyl ligand; the inorganic vanadium source is a vanadium-containing halide. In another embodiment, the organochromium source of the present invention has the structural formula: crCp 1Cp2, wherein Cp 1 and Cp 2 are independently one of cyclopentadienyl, indenyl and fluorenyl, and Cp 1 is the same or different from Cp 2; specifically, the structures of Cp 1 and Cp 2 are one of the following structures:
in another embodiment, the vanadium source of the present invention is selected from at least one of vanadium trifluoride, vanadium trichloride, vanadium tribromide, vanadium tetrafluoride, vanadium tetrachloride, vanadyl difluoride, vanadyl dichloride, vanadyl dibromide, vanadyl trifluoride, vanadyl trichloride.
In one embodiment, the method of loading the precursor of the active component onto the modified support of the present invention is impregnation. The invention is not particularly limited to the sequence of impregnating the chromium active component and the vanadium active component, and the impregnation may be performed simultaneously or stepwise.
In another embodiment, the carrier impregnating active components of the present invention are: the active component precursor is dissolved in an inert organic solvent, and a vanadium source and a chromium source enter porous inorganic carrier pore channels through a dipping and stirring method and are adsorbed on the surfaces of the porous inorganic carrier pore channels. Wherein the inert organic solvent can be at least one of n-hexane, n-heptane, n-octane, benzene, toluene, xylene, etc. The dosages of the chromium source and the vanadium source are as follows: the inorganic vanadium active component accounts for 0.1 to 10 weight percent of the total weight of the catalyst based on V; the organic chromium active component accounts for 0.1-8wt% of the total weight of the catalyst based on Cr. Wherein the temperature of the impregnation can be 20-180 ℃, preferably 45-120 ℃, and the time of the impregnation can be 1-24 hours, preferably 4-12 hours; the solvent in the system is evaporated and removed at high temperature after the impregnation is finished to achieve the aim of drying, wherein the drying is performed at 60-150 ℃, preferably at 80-130 ℃, and the drying time is 2-24 hours, preferably 6-16 hours.
The method utilizes the roasting activated carrier to impregnate the precursor of the active component to obtain the catalyst, thus the active metal can be loaded on the carrier, the obtained catalyst does not need the traditional roasting step, and the aggregation phenomenon of the active metal in the roasting process can be prevented.
As a specific embodiment, the invention provides a preparation method of a supported double-center catalyst, which comprises the following steps:
(1.1) high-temperature roasting the carrier to remove physical water and part of hydroxyl groups on the surface of the carrier;
(1.2) placing the carrier treated in the step (1.1) and a modifier (organic aluminum compound) into an organic solvent for reaction to obtain a modified carrier;
(1.3) co-impregnating the modified carrier obtained in the step (1.2) and an organic chromium source in an organic solvent for reaction to form a catalyst precursor with the surface of the carrier loaded with the organic chromium;
(1.4) co-impregnating the product obtained in the step (1.3) and a vanadium source in an organic solvent for reaction to form a catalyst with the surface of the carrier loaded with organic chromium and inorganic vanadium;
the order of the steps (1.3) and (1.4) is not particularly limited, and the step (1.3) and the step (1.4) may be performed first, or the step (1.4) and the step (1.3) may be performed first, or the step (1.3) and the step (1.4) may be performed simultaneously, that is, the organic chromium source, the inorganic vanadium source and the modified carrier are co-impregnated in an organic solvent.
The supported double-center catalyst prepared by the invention takes the total mass of the supported double-center catalyst as a reference, the active component of the supported double-center catalyst is 0.1 to 8 weight percent of Cr, 0.1 to 10 weight percent of V and the modifier is 0.1 to 10 weight percent of metal.
The supported double-center catalyst can be used for ethylene homopolymerization and copolymerization of ethylene and alpha-olefin, wherein the polymerized monomer can be ethylene or common alpha-olefin, and common alpha-olefin comprises propylene, 1-butene, 1-hexene and 1-octene, and the molecular weight of the synthesized polymer is in wide and bimodal distribution and comprises lower molecular weight ethylene homopolymers and higher molecular weight ethylene copolymers.
The supported double-center catalyst also comprises an activation step of the catalyst when catalyzing olefin polymerization or before being used for olefin polymerization, and the activation reagent is an alkyl aluminum compound.
In one embodiment, the pre-reduction activation treatment of the supported double site catalyst with the alkyl aluminum compound is performed under an inert atmosphere, and the ratio of the molar amount of the alkyl aluminum compound to the total molar amount of chromium element in the supported double site catalyst is 0 to 1000, preferably 0 to 100, more preferably 0 to 50; the pre-reduction activation treatment temperature is between room temperature and 100 ℃, preferably between room temperature and 60 ℃, the reduction activation treatment time is between 0.5 and 20 hours, preferably between 0.5 and 10 hours, the reduction activation treatment mode can be that the catalyst and the activator are immersed in an organic solvent, stirring can be carried out, stirring is preferred to be continuous, drying is carried out for 2 to 8 hours at the temperature of between 60 and 120 ℃ after the treatment is finished, drying is carried out under nitrogen or inert gas atmosphere, for example, under nitrogen, helium, argon and other atmospheres, preferably under nitrogen atmosphere, the drying process can be carried out under vacuum condition, and the obtained supported double-active-center catalyst subjected to pre-reduction activation is stored for standby under inert gas atmosphere.
In the step of activating the supported double active center catalyst, the in-situ formation of the target catalyst by the reaction of the supported double active center catalyst and the alkylaluminum compound means that in-situ reduction activation treatment is carried out in a solvent medium, wherein the solvent medium can be selected from at least one of isopentane, n-pentane, n-hexane, isohexane, n-heptane, n-octane, toluene and xylene, preferably isopentane, n-hexane, isohexane and n-heptane; the ratio of the molar amount of the alkyl aluminum compound to the molar amount of the chromium element in the supported double-center catalyst is 0 to 1000, preferably 0 to 100, more preferably 0 to 50; the temperature of the in-situ reduction and activation treatment is 20-120 ℃, and the time of the in-situ reduction and activation treatment is 0.5-5 h.
In embodiment I, the method for preparing the supported dual active site catalyst of the present invention comprises the steps of:
(I) Roasting and activating the porous inorganic carrier at 200-900 ℃;
(II) immersing the roasted porous inorganic carrier in a solution containing alkyl aluminum for reacting for a period of time, and then drying for later use;
(III) immersing the product obtained in the step (II) in a solution containing a vanadium source for reacting for a period of time, and then drying and preserving;
(IV) immersing the product obtained in the step (III) in a solution containing an organic chromium source, and then drying to obtain the catalyst for storage;
according to a preferred method for preparing a supported double site catalyst, the method comprises the steps of:
a) The porous inorganic carrier is placed in inert gas for high-temperature roasting at 200-900 ℃, preferably 300-600 ℃ for 1-10 hours, preferably 2-4 hours, and then naturally cooled to room temperature and stored for standby.
B) Immersing the roasted inorganic carrier in an organic solvent containing alkyl aluminum for 1-12 hours, preferably 1-4 hours, wherein the reaction temperature is between room temperature and 180 ℃, preferably 45-120 ℃, then heating to 60-210 ℃ for drying, preferably 80-150 ℃, and the drying time is between 2 and 12 hours, preferably 2-4 hours, and transferring the dried product to inert gas for standby.
C) And c) immersing the product in the solution containing the vanadium source in the b) for reaction loading for 1-24 hours, preferably 4-12 hours, wherein the immersing temperature is 20-180 ℃, preferably 45-120 ℃, then drying at 60-150 ℃, preferably 80-130 ℃, and drying for 2-24 hours, preferably 6-16 hours, wherein vacuum can be adopted in the drying process, and then the dried mixture is preserved under the protection of inert gas for standby.
D) And (3) placing the product into a solution containing an organic chromium source for carrying out impregnation reaction, wherein the impregnation reaction time is 1-24 hours, preferably 4-8 hours, the impregnation temperature is 20-120 ℃, preferably 45-80 ℃, then drying is carried out at 60-150 ℃, preferably 80-100 ℃, the drying time is 2-24 hours, preferably 6-16 hours, vacuum can be adopted in the drying process, and the catalyst is obtained after the drying is finished.
As an example, specific operations for preparing the catalyst of the present invention include:
The SiO 2 carrier is placed in a fluidized bed for high-temperature roasting, the roasting process is carried out under the atmosphere of nitrogen, and the roasting temperature is 600 ℃. After the calcination is completed for a specified period of time (e.g., 2-4 hours), the heating is stopped, and the dried and partially dehydroxylated SiO 2 is naturally cooled to room temperature, and then collected and stored in an atmosphere protected by an inert gas (e.g., nitrogen). And (3) carrying out blending reaction on the roasted carrier and a triethylaluminum toluene solution with a certain concentration, wherein the addition amount of triethylaluminum calculated by aluminum is 1wt% relative to the total weight of the catalyst, carrying out the reaction at 80 ℃, continuously stirring, heating to 130 ℃ after the reaction is carried out for about 2 hours, and drying for 4-6 hours, wherein nitrogen is introduced in the drying process to accelerate the drying. And (5) placing the dried modified carrier under the protection of inert gas for standby. Immersing the product in a solution containing VOCl 3 n-hexane with a certain concentration, wherein the addition amount of vanadium is in accordance with the requirement of the invention relative to the total weight of the catalyst (for example, the addition amount of V is 0.2-3 wt%); after continuously stirring and reacting for a certain time (for example, 4-8 hours) at a certain temperature (for example, 45-80 ℃), washing the catalyst with normal hexane at a certain temperature (for example, room temperature-60 ℃), and drying for 4-6 hours at a certain temperature (for example, 60-120 ℃), wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas. Immersing the product loaded with a certain vanadium catalyst precursor in an n-hexane solution containing dicyclopentadienyl chromium with a certain concentration, wherein the addition amount of the chromium meets the requirement of the invention relative to the total weight of the catalyst (for example, the addition amount of the Cr is 0.2-2 wt%); continuously stirring at a certain temperature (such as 45-80 ℃) for reacting for a certain time (such as 4-8 hours), and drying at a certain temperature (such as 60-120 ℃) for 4-6 hours, wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas.
In embodiment II, the present invention provides a method for preparing a supported dual-site catalyst comprising the steps of:
(I) Roasting and activating the porous inorganic carrier at 200-900 ℃;
(II) immersing the roasted porous inorganic carrier in a solution containing alkyl aluminum for reacting for a period of time, and then drying for later use;
(III) immersing the product obtained in the step (II) in a solution containing an organic chromium source for reacting for a period of time, and then drying and preserving;
(IV) immersing the product obtained in the step (III) in a solution containing a vanadium source, and then drying to obtain the catalyst precursor, and storing the catalyst precursor for later use;
According to a preferred method for preparing a supported dual site ethylene polymerization catalyst, the method comprises the steps of:
a) The porous inorganic carrier is placed in inert gas for high-temperature roasting at 200-900 ℃, preferably 300-600 ℃ for 1-10 hours, preferably 2-4 hours, and then naturally cooled to room temperature and stored for standby.
B) Immersing the roasted inorganic carrier in an organic solvent containing alkyl aluminum for 1-12 hours, preferably 1-4 hours, wherein the reaction temperature is between room temperature and 180 ℃, preferably 45-120 ℃, then heating to 60-210 ℃ for drying, preferably 80-150 ℃, and the drying time is between 2 and 12 hours, preferably 2-4 hours, and transferring the dried product to inert gas for standby.
C) And (3) placing the product into a solution containing an organic chromium source for carrying out impregnation reaction, wherein the impregnation reaction time is 1-24 hours, preferably 4-8 hours, the impregnation temperature is 20-120 ℃, preferably 45-80 ℃, then drying is carried out at 60-150 ℃, preferably 80-100 ℃, the drying time is 2-24 hours, preferably 6-16 hours, vacuum can be adopted in the drying process, and the catalyst precursor is obtained after the drying is finished.
D) The product is immersed in a solution containing vanadium source for reaction loading for 1-24 h, preferably 4-12 h, the immersing temperature is 20-180 ℃, preferably 45-120 ℃, then the product is dried at 60-150 ℃, preferably 80-130 ℃, the drying time is 2-24 h, preferably 6-16 h, vacuum can be adopted in the drying process, and the dried mixture is preserved under the protection of inert gas for standby.
As an example, specific operations for preparing the catalyst of the present invention include:
The SiO 2/TiO2 (containing 5wt% Ti) carrier is placed in a fluidized bed to be roasted at high temperature, the roasting process is carried out under the nitrogen atmosphere, and the roasting temperature is 600 ℃. After the calcination is completed for a specified period of time (e.g., 2-4 hours), the heating is stopped, and the dried and partially dehydroxylated SiO 2/TiO2 is naturally cooled to room temperature, and then collected and stored in an atmosphere protected by an inert gas (e.g., nitrogen). And (3) carrying out blending reaction on the roasted carrier and a triisobutylaluminum n-hexane solution with a certain concentration, wherein the addition amount of triisobutylaluminum calculated by aluminum is 1wt% relative to the total weight of the catalyst, the reaction is carried out at 45 ℃, continuous stirring is carried out, the temperature is raised to 80 ℃ after the reaction is carried out for about 2 hours, and drying is carried out for 4-6 hours, and nitrogen is introduced in the drying process to accelerate the drying. And (5) placing the dried modified carrier under the protection of inert gas for standby. Immersing the modified carrier in a normal hexane solution containing bisindenyl chromium with a certain concentration, wherein the addition amount of chromium meets the requirement of the invention relative to the total weight of the catalyst (for example, the addition amount of Cr is 0.2-1 wt%); continuously stirring at a certain temperature (such as 45-80 ℃) for reacting for a certain time (such as 4-8 hours), and drying at a certain temperature (such as 60-120 ℃) for 4-8 hours, wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas. Immersing the product loaded with a certain organic chromium catalyst precursor in a solution containing VOCl 3 n-hexane with a certain concentration, wherein the addition amount of vanadium is in accordance with the requirement of the invention relative to the total weight of the catalyst (for example, the addition amount of V is 0.2-2 wt%); after continuously stirring and reacting for a certain time (for example, 4-8 hours) at a certain temperature (for example, 45-80 ℃), washing the catalyst with normal hexane at a certain temperature (for example, room temperature-60 ℃), and drying for 4-6 hours at a certain temperature (for example, 60-120 ℃), wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas.
In embodiment iii, the present invention provides a method for preparing a supported dual-site catalyst comprising the steps of:
(I) Roasting and activating the porous inorganic carrier at 200-900 ℃;
(II) immersing the roasted porous inorganic carrier in a solution containing alkyl aluminum for reacting for a period of time, and then drying for later use;
(III) immersing the product obtained in the step (II) in a solution containing an organic chromium source and a vanadium source for reacting for a period of time, and then drying and preserving;
According to a preferred method for preparing a supported dual site ethylene polymerization catalyst, the method comprises the steps of:
a) The porous inorganic carrier is placed in inert gas for high-temperature roasting at 200-900 ℃, preferably 300-600 ℃ for 1-10 hours, preferably 2-4 hours, and then naturally cooled to room temperature and stored for standby.
B) Immersing the roasted inorganic carrier in an organic solvent containing alkyl aluminum for 1-12 hours, preferably 1-4 hours, wherein the reaction temperature is between room temperature and 180 ℃, preferably 45-120 ℃, then heating to 60-210 ℃ for drying, preferably 80-150 ℃, and the drying time is between 2 and 12 hours, preferably 2-4 hours, and transferring the dried product to inert gas for standby.
C) The product is put into a solution containing an organic chromium source and a vanadium source for carrying out impregnation reaction, the impregnation reaction time is 2-24 hours, preferably 4-8 hours, the impregnation temperature is 20-120 ℃, preferably 45-80 ℃, then the product is dried at 60-150 ℃, preferably 80-120 ℃, the drying time is 2-24 hours, preferably 6-16 hours, vacuum can be adopted in the drying process, the catalyst precursor is obtained after the drying is finished, and then the dried product is preserved under the protection of inert gas for standby.
As an example, specific operations for preparing the catalyst of the present invention include:
The SiO 2 carrier is placed in a fluidized bed for high-temperature roasting, the roasting process is carried out under the atmosphere of nitrogen, and the roasting temperature is 500 ℃. After the calcination is completed for a specified period of time (e.g., 2-4 hours), the heating is stopped, and the dried and partially dehydroxylated SiO 2 is naturally cooled to room temperature, and then collected and stored in an atmosphere protected by an inert gas (e.g., nitrogen). And (3) carrying out blending reaction on the roasted carrier and a triethylaluminum toluene solution with a certain concentration, wherein the addition amount of triethylaluminum calculated by aluminum is 1wt% relative to the total weight of the catalyst, carrying out the reaction at 80 ℃, continuously stirring, heating to 130 ℃ after the reaction is carried out for about 2 hours, and drying for 4-6 hours, wherein nitrogen is introduced in the drying process to accelerate the drying. And (5) placing the dried modified carrier under the protection of inert gas for standby.
Immersing the product in an n-hexane solution containing dicyclopentadienyl chromium and VOCl 3 with certain concentration, wherein the addition amount of chromium and vanadium meets the requirements of the invention relative to the total weight of the catalyst (for example, the addition amount of Cr is 0.2-2 wt%, and the addition amount of V is 0.2-1.5 wt%); after continuously stirring and reacting for a certain time (for example, 4-8 hours) at a certain temperature (for example, 45-60 ℃), washing the catalyst with normal hexane at a certain temperature (for example, room temperature-60 ℃), and drying for 4-8 hours at a certain temperature (for example, 60-120 ℃), wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas.
In embodiment IV, the present invention provides a method for preparing a supported dual-site catalyst comprising the steps of:
(I) Roasting and activating the porous inorganic carrier at 200-900 ℃;
(II) immersing the roasted porous inorganic carrier in a solution containing alkyl aluminum for reacting for a period of time, and then drying for later use;
(III) immersing the product obtained in the step (II) in a solution containing a vanadium source for reacting for a period of time, and then drying and preserving;
(IV) immersing the product obtained in the step (III) in a solution containing an organic chromium source, and then drying to obtain the catalyst for storage;
And (V) immersing the catalyst obtained in the step (IV) in an organic metal cocatalyst solution for pre-reduction activation to obtain the catalyst with catalytic activity.
According to one preferred method of preparing a supported dual site ethylene polymerization catalyst, the method comprises the steps of:
a) The porous inorganic carrier is placed in inert gas for high-temperature roasting at 200-900 ℃, preferably 300-600 ℃ for 1-10 hours, preferably 2-4 hours, and then naturally cooled to room temperature and stored for standby.
B) Immersing the roasted inorganic carrier in an organic solvent containing alkyl aluminum for 1-12 hours, preferably 1-4 hours, wherein the reaction temperature is between room temperature and 180 ℃, preferably 45-120 ℃, then heating to 60-210 ℃ for drying, preferably 80-150 ℃, and the drying time is between 2 and 12 hours, preferably 2-4 hours, and transferring the dried product to inert gas for standby.
C) The product is immersed in a solution containing vanadium source for reaction loading for 1-24 h, preferably 4-12 h, the immersing temperature is 20-180 ℃, preferably 45-120 ℃, then the product is dried at 60-150 ℃, preferably 80-130 ℃, the drying time is 2-24 h, preferably 6-16 h, vacuum can be adopted in the drying process, and the dried mixture is preserved under the protection of inert gas for standby.
D) And (3) placing the product into a solution containing an organic chromium source for carrying out impregnation reaction, wherein the impregnation reaction time is 1-24 hours, preferably 4-8 hours, the impregnation temperature is 20-120 ℃, preferably 45-80 ℃, then drying is carried out at 60-150 ℃, preferably 80-100 ℃, the drying time is 2-24 hours, preferably 6-16 hours, vacuum can be adopted in the drying process, and the catalyst is obtained after the drying is finished.
E) Placing the product in a solution containing an organometallic cocatalyst for activation reaction, wherein the molar ratio of the organometallic cocatalyst to chromium element is 0-1000, preferably 0-100, more preferably 0-50; the activation reaction time is 0.5-20 h, preferably 1-2 h, the activation temperature is between room temperature and 100 ℃, preferably between room temperature and 60 ℃, then the catalyst is dried at 60-120 ℃, preferably 80-100 ℃ for 2-8 h, vacuum can be adopted in the drying process, and the catalyst with activity is obtained after the drying is finished. And (5) preserving the dried catalyst under the protection of inert gas atmosphere for later use.
As an example, specific operations for preparing the catalyst of the present invention include:
The SiO 2 carrier is placed in a fluidized bed for high-temperature roasting, the roasting process is carried out under the atmosphere of nitrogen, and the roasting temperature is 600 ℃. After the calcination is completed for a specified period of time (e.g., 2-4 hours), the heating is stopped, and the dried and partially dehydroxylated SiO 2 is naturally cooled to room temperature, and then collected and stored in an atmosphere protected by an inert gas (e.g., nitrogen). And (3) carrying out blending reaction on the roasted carrier and a methyl aluminoxane toluene solution with a certain concentration, wherein the adding amount of methyl aluminoxane calculated by aluminum is 1wt% relative to the total weight of the catalyst, carrying out the reaction at 80 ℃, continuously stirring, heating to 130 ℃ after the reaction is carried out for about 2 hours, and drying for 4-6 hours, wherein nitrogen is introduced in the drying process to accelerate the drying. And (5) placing the dried modified carrier under the protection of inert gas for standby. Immersing the product in a solution containing VOCl 3 n-hexane with a certain concentration, wherein the addition amount of vanadium is in accordance with the requirement of the invention relative to the total weight of the catalyst (for example, the addition amount of V is 0.2-3 wt%); after continuously stirring and reacting for a certain time (for example, 4-8 hours) at a certain temperature (for example, 45-80 ℃), washing the catalyst with normal hexane at a certain temperature (for example, room temperature-60 ℃), and drying for 4-6 hours at a certain temperature (for example, 60-120 ℃), wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas. Immersing the product loaded with a certain vanadium catalyst precursor in an n-hexane solution containing dicyclopentadienyl chromium with a certain concentration, wherein the addition amount of the chromium meets the requirement of the invention relative to the total weight of the catalyst (for example, the addition amount of the Cr is 0.2-2 wt%); continuously stirring at a certain temperature (such as 45-80 ℃) for reacting for a certain time (such as 4-8 hours), and drying at a certain temperature (such as 60-120 ℃) for 4-6 hours, wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas. The catalyst is added into a normal hexane solution of triethylaluminum (the mole ratio of triethylaluminum to chromium in a catalyst precursor is 30:1), and then the catalyst is continuously stirred and reacted for a certain time (for example, 2 hours) at a certain temperature (for example, 60 ℃), and then dried for 2 to 4 hours at a certain temperature (for example, 85 ℃), wherein the drying process is carried out under the environment of inert gases such as nitrogen, argon and helium. And transferring and storing the dried product under the protection of inert gas.
The supported double-center catalyst can be used for catalyzing olefin polymerization, and is particularly suitable for catalyzing homo-polymerization of ethylene or copolymerization of ethylene and alpha-olefin.
The olefin generally comprises ethylene monomer and may also comprise comonomer; the comonomer may be an alpha-olefin having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-methyl-1-pentene, 4-methyl-1-hexene, etc., which may be used alone or in combination of two or more. The comonomer is preferably at least one of 1-butene, 1-hexene and 1-octene; when present, the amount of comonomer is generally from 0 to 20% by volume, preferably from 0 to 10% by volume, based on the volume concentration of the comonomer relative to the solvent at the time of polymerization.
When the supported double-center catalyst is used for catalyzing the homopolymerization of ethylene or the copolymerization of ethylene and alpha-olefin, the produced polyethylene product has the following characteristics: the molecular weight distribution is wider when ethylene homopolymerization is carried out, and part of the molecular weight is in bimodal distribution; when the copolymerization of ethylene and alpha-olefin is carried out, the molecular weight distribution is wider, the part of the molecular weight distribution is bimodal, and the copolymer contains lower molecular weight ethylene homopolymer and higher molecular weight ethylene and alpha-olefin.
In the invention, in the process of catalyzing olefin polymerization, an organic metal cocatalyst, a molecular weight regulator and the like can be added according to the need; the organometallic co-catalyst may be an organoaluminum compound such as at least one of trialkylaluminum AlR 3, dialkylaluminum alkoxide AlR 2 OR, dialkylaluminum halide AlR 2 X, aluminoxane, ethyl aluminum sesquichloride, where R is an alkyl group. More examples are triethylaluminum, triisobutylaluminum, diethylaluminum ethoxide, diethylaluminum monochloride, methylaluminoxane and the like. The use amount of the organometallic aluminum compound satisfies the following conditions: the molar ratio of aluminum element to total chromium element is 0 to 1000, preferably 0 to 70, more preferably 0 to 50; the molecular weight adjustment may be hydrogen.
The supported double-center catalyst of the present invention is not particularly limited in its method of polymerization in catalyzing olefin polymerization, and when used in catalyzing homo-polymerization of ethylene or copolymerization of ethylene and α -olefin, the polymerization method may include a gas phase polymerization process, a slurry polymerization process, a suspension polymerization process, a bulk polymerization process, a solution polymerization process, etc., which are carried out under conventional embodiments and polymerization conditions.
Preferably, when the polymerization is carried out using a slurry polymerization process, the polymerization is initiated by adding ethylene to the reaction vessel, then adding the solvent and cocatalyst (organoaluminum compound) and optionally hydrogen and comonomer, and finally adding the supported dual-site catalyst of the invention. The solvent used therein is generally any solvent known in the art for olefin polymerization and may be an alkane having 3 to 20 carbon atoms such as propane, n-butane, isobutane, n-pentane, isopentane, neopentane, n-hexane, cyclohexane, n-heptane, n-octane, etc.; these solvents may be used singly or in combination of two or more. The solvent used is preferably isobutane, isopentane, n-hexane, cyclohexane, n-heptane or the like.
More preferably, when the polymerization is carried out using a conventional slurry polymerization process, the specific operations are as follows: firstly, carrying out vacuum heating and impurity removal on a polymerization reaction kettle, then replacing the polymerization reaction kettle with high-purity nitrogen, repeatedly operating for three times, replacing the polymerization reaction kettle with a small amount of ethylene monomer once, and finally filling ethylene into the reaction kettle to micro positive pressure (0.12 MPa); adding a dehydrated and deoxidized refined solvent such as n-heptane and a certain amount of alkyl aluminum as a cocatalyst into a reaction kettle, respectively adding a certain amount of hydrogen and a comonomer into a hydrogen blending copolymerization experiment, adjusting the ethylene pressure to 1MPa, and finally adding the catalyst to start polymerization reaction; the instantaneous consumption of monomer ethylene is collected online in the reaction process and recorded by a computer, and after the reaction is carried out for a certain time (for example, 1 hour) at a certain temperature (for example, 35 ℃ to 100 ℃), the mixed solution of hydrochloric acid and ethanol is added to terminate the reaction; the polymer was washed, dried in vacuo, weighed and analyzed.
The present invention will be described in further detail with reference to examples, but embodiments of the present invention are not limited thereto.
The reagents used in the examples are commercially available as usual unless otherwise specified.
The various polymer properties in the examples were measured according to the following methods:
high temperature gel chromatography (HT-GPC)
Weight average molecular weight and molecular weight distribution were determined by high temperature gel chromatography: the molecular weight and molecular weight distribution of polyethylene were determined in this experiment using a PL-220 type high temperature gel permeation chromatograph (Polymer Laboratories Co.). In the experiment, 1,2, 4-trichlorobenzene was used as a solvent and was measured at 160 ℃. And processing data by adopting a universal correction method with narrow-distribution polystyrene as a standard sample.
13 C high temperature nuclear magnetic resonance spectrum (HT- 13 CNMR)
The short chain branch content of the polymer is determined by a high Wen Heci carbon spectrum: the test adopts BrukerAvance III 500 nuclear magnetic resonance apparatus to measure the short branched chain content of polyethylene. In the experiment, deuterated paradichlorobenzene is used as a solvent, and the short-chain branch content is calculated by taking a carbon signal (displacement is 30.00 ppm) on a polyethylene main chain as an internal standard in measurement at 110 ℃.
Example 1:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. Immersing the roasted carrier in a normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of Al is 1wt% relative to the total weight of the catalyst), reacting for 2 hours at 45 ℃, then heating to 85 ℃, keeping the temperature for 4 hours to remove normal hexane solvent, and transferring the product to anhydrous and anaerobic conditions for preservation under the protection of nitrogen after drying. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Example 2:
10g of SiO 2 (specific surface area 300m2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken to be roasted, dehydrated and subjected to hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to an anhydrous and anaerobic condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. And (3) adding the dried product into a triisobutylaluminum n-hexane solution (the molar ratio of A1 to Cr is 10) for activation reaction, wherein the activation reaction temperature is 45 ℃, the activation time is 1h, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4h, stirring is applied in the soaking and drying processes, and after the drying is finished, the catalyst is transferred to an anhydrous and anaerobic condition for preservation under the protection of nitrogen.
Example 3:
10g of SiO 2 (specific surface area 300 m/g, pore volume 1.3ml/g and pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Example 4:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to an n-hexane solution containing vanadium oxychloride and biscyclopentadienyl chromium to carry out a reflux impregnation load reaction (the load amounts of Cr and V were 1wt% and 2wt%, respectively, relative to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, and then the impregnated product was washed 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 5-1 to 5-4:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g and pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, when the specified roasting temperature is reached (the specified roasting temperatures of examples 5-1 to 5-4 are 300 ℃,400 ℃,600 ℃ and 800 ℃ respectively), the temperature is kept for 2 hours, natural cooling is started to room temperature after the roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 6-1 to 6-4:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load of V of examples 6-1 to 6-4 was 0.5wt%, 1wt%, 3wt% and 5wt%, respectively, relative to the total weight of the catalyst) for 4 hours at a reflux impregnation temperature of 85 ℃, followed by 3 washes of the impregnate with n-hexane, each wash being 100mL with n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 7-1 to 7-4:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. The above dried product was immersed in a normal hexane solution of biscyclopentadienyl chromium (Cr loadings of 0.5wt%, 2wt%, 3wt% and 4wt% respectively, based on the total weight of the catalyst in examples 7-1 to 7-4), the immersion temperature was 45 ℃, the immersion time was 6 hours, then the drying was carried out at a temperature of 80 ℃ for 4 hours, stirring was applied during the immersion and drying processes, and after the drying was completed, the catalyst precursor was transferred to anhydrous and anaerobic conditions under nitrogen protection for preservation.
Examples 8-1 to 8-3:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The calcined support was immersed in a normal hexane solution containing triisobutylaluminum at a concentration (Al loadings of 0.5wt%, 1.5wt% and 2wt% respectively in examples 8-1 to 8-3 relative to the total weight of the catalyst), reacted at 45℃for 2 hours, then warmed to 85℃and kept at constant temperature for 4 hours to remove normal hexane solvent, and after drying, the product was transferred to anhydrous and anaerobic conditions under nitrogen protection and stored. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 9-1 to 9-2:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to a solution of vanadium halide (vanadium halide was vanadium tetrachloride and vanadium tribromide in examples 9-1 to 9-2, respectively) in n-hexane for a reflux impregnation supporting reaction (the supporting amount of V was 2% by weight relative to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, and then the impregnation was washed 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 10-1 to 10-2:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. Immersing the roasted carrier in a normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of Al is 1wt% relative to the total weight of the catalyst), reacting for 2 hours at 45 ℃, then heating to 85 ℃, keeping the temperature for 4 hours to remove normal hexane solvent, and transferring the product to anhydrous and anaerobic conditions for preservation under the protection of nitrogen after drying. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. The above dried product was immersed in an n-hexane solution of organic chromium sources (organic chromium sources of examples 10-1 to 10-2 are respectively bifluorenylchromium and bisindenyl chromium) (the loading amount of Cr was 1wt% relative to the total weight of the catalyst) at 45℃for 6 hours, followed by drying at 80℃for 4 hours at elevated temperature, stirring was applied during the immersing and drying processes, and the catalyst precursor was transferred to an anhydrous and anaerobic condition under nitrogen protection after the drying was completed and stored.
Examples 11-1 to 11-2:
10g of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The calcined carrier is immersed in n-hexane solution containing a certain concentration of alkyl aluminum (the alkyl aluminum adopted in examples 11-1 and 11-2 is trimethyl aluminum and triethyl aluminum respectively, and the loading amount of Al is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃, the temperature is kept constant for 4 hours to remove the n-hexane solvent, and after the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 12-1 to 12-2:
10g of a porous inorganic carrier (porous inorganic carriers of examples 12-1 to 12-2 were each SiO 2/TiO2 (containing 3wt% Ti, specific surface area 320m 2/g, pore volume 1.5ml/g, pore diameter 23 nm) and SiO 2/ZrO2 (containing 5wt% Zr, specific surface area 500m 2/g, pore volume 1.7ml/g, pore diameter 21 nm)) were taken in a fluidized bed, and subjected to calcination dehydration and dehydroxylation treatment at a heating rate of 5 ℃/min, constant temperature was maintained for 2 hours when 500℃was reached, natural cooling to room temperature was started after the completion of calcination, and the mixture was transferred to a dry and anaerobic condition for preservation. Immersing the roasted carrier in a normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of Al is 1wt% relative to the total weight of the catalyst), reacting for 2 hours at 45 ℃, then heating to 85 ℃, keeping the temperature for 4 hours to remove normal hexane solvent, and transferring the product to anhydrous and anaerobic conditions for preservation under the protection of nitrogen after drying. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Examples 13-1 to 13-4:
100mg of the catalyst precursor in examples 1 to 4 was weighed and mixed in 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 14-1 to 14-4:
100mg of the catalyst precursor in examples 5-1 to 5-4 was weighed and mixed in 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 15-1 to 15-4:
100mg of the catalyst precursor in examples 6-1 to 6-4 was weighed and mixed in 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 16-1 to 16-4:
100mg of the catalyst precursor in examples 7-1 to 7-4 was weighed and mixed in 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of AI/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 17-1 to 17-3:
100mg of the catalyst precursor in examples 8-1 to 8-3 was weighed and mixed in 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 18-1 to 18-4:
100mg of the catalyst precursor in examples 9-1 and 9-2 and examples 10-1 and 10-2 was weighed and mixed in 10ml of purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 19-1 to 19-2:
100mg of the catalyst precursor in examples 11-1 and 11-2 was weighed and mixed with 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 20-1 to 20-2:
100mg of the catalyst precursor in examples 12-1 and 12-2 was weighed and mixed with 10ml of purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 21-1 to 21-4:
100mg of the catalyst precursor in example 1 was weighed and mixed with 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900ml of purified n-heptane solvent was sequentially added to the reaction vessel. For examples 21-1 to 21-4, triisobutylaluminum (TIBA) was added as a cocatalyst in amounts of Al/cr=10, al/cr=20, al/cr=40 and Al/cr=50, respectively (Cr is the total molar amount of chromium added to the catalyst), and 100mL of dehydrated, deoxidized and purified n-heptane solvent was further added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 22-1 to 22-3:
100mg of the catalyst precursor in example 1 was weighed and mixed with 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900ml of purified n-heptane solvent was sequentially added to the reaction vessel. For examples 22-1 to 22-3, triethylaluminum (TEA), diethylaluminum chloride (DEAC) and Methylaluminoxane (MAO) were added as cocatalysts in amounts of Al/cr=30 (Cr is the total chromium molar amount of catalyst added), respectively, and 100mL of dehydrated, deoxygenated and refined n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 23-1 to 23-4:
100mg of the catalyst precursor in example 1 was weighed and mixed with 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. For examples 23-1 to 23-4, 10mL, 30mL, 50mL and 70mL of 1-hexene comonomer were injected into the reaction vessel, respectively. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Examples 24-1 to 24-4
100Mg of the catalyst precursor in example 1 was weighed and mixed with 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was sequentially introduced into the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the molar amount of total chromium) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. For examples 24-1 to 24-4, high purity hydrogen of 0.03MPa, 0.05MPa, 0.1MPa and 0.2MPa was injected into the reaction vessel, respectively. And then adjusting the ethylene partial pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Comparative example 1
10G of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Comparative example 2
10G of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Comparative example 3
10G of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Comparative example 4
10G of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The carrier after roasting treatment is immersed in normal hexane solution containing triisobutylaluminum with a certain concentration (the loading of A1 is 1wt% relative to the total weight of the catalyst) to react for 2 hours at 45 ℃, then the temperature is raised to 85 ℃ and kept constant for 4 hours to remove normal hexane solvent, and after the drying is finished, the product is transferred to anhydrous and anaerobic condition for preservation under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Comparative example 5
10G of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) is taken and subjected to roasting dehydration and hydroxyl removal treatment in a fluidized bed, the heating rate is 5 ℃/min, the temperature is kept constant for 2 hours when the temperature reaches 500 ℃, natural cooling is started to room temperature after roasting is finished, and the roasting is transferred to a water-free and oxygen-free condition for preservation. The above product was added to a vanadium oxychloride n-hexane solution to carry out a reflux impregnation load reaction (the load amount of V was 2wt% with respect to the total weight of the catalyst), the reflux impregnation time was 4 hours, the reflux impregnation temperature was 85 ℃, followed by washing the impregnated product 3 times with n-hexane, each washing with 100mL of n-hexane. The reflux was then stopped and the temperature was raised to 120℃and kept constant for 4 hours to remove the n-hexane solvent. After the drying is finished, the product is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen. Immersing the dried product in a bis-cyclopentadienyl chromium n-hexane solution (the load of Cr is 1wt% relative to the total weight of the catalyst), wherein the immersion temperature is 45 ℃, the immersion time is 6 hours, then heating and drying are carried out, the drying temperature is 80 ℃, the drying time is 4 hours, stirring is applied in the immersion and drying processes, and after the drying is finished, the catalyst precursor is transferred to an anhydrous and anaerobic condition for storage under the protection of nitrogen.
Comparative example 6
10G of SiO 2 (specific surface area 300m 2/g, pore volume 1.3ml/g, pore diameter 20 nm) was immersed in an aqueous solution of ammonium metavanadate (the loading of V was 2wt% relative to the total weight of the catalyst), continuously stirred and immersed for about 4 hours at a temperature of 60℃and then heated to 120℃and continuously stirred and dried for 8 hours. And (3) placing the dried mixture in a fluidized bed, heating and roasting from room temperature, wherein the heating rate is 1 ℃/min, keeping the temperature constant for 4 hours when the temperature reaches 500 ℃, naturally cooling to room temperature after roasting, and transferring to an anhydrous and anaerobic condition for preservation. In the process, nitrogen atmosphere is adopted from room temperature to 150 ℃, dry air atmosphere is adopted in the temperature rising stage of 150-500 ℃, dry air atmosphere is adopted in the constant temperature stage of 500 ℃, the temperature is reduced from 500 ℃ to 300 ℃ when the temperature is naturally cooled, and the temperature is switched to nitrogen atmosphere when the temperature is lower than 300 ℃. Immersing the dried product in a normal hexane solution of dicyclopentadienyl chromium at 45 ℃ for 6 hours, then heating and drying at 80 ℃ for 4 hours, stirring during the immersing and drying processes, and transferring the catalyst precursor to anhydrous and anaerobic conditions for preservation under the protection of nitrogen after the drying is finished.
Comparative examples 7-1 to 7-6
100Mg of the catalyst precursor in comparative examples 1 to 6 was weighed and mixed in 10ml of a purified n-heptane solution to form a catalyst precursor suspension, and polymerization experiments were conducted. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of Al/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
Comparative examples 8-1 to 8-5
100Mg of the catalyst precursor was weighed, wherein comparative examples 8-1 to 8-5 correspond to the catalysts prepared in comparative examples 1-5, respectively, and the weighed catalysts were mixed in 10ml of purified n-heptane solution to form a catalyst precursor suspension. And (3) carrying out vacuum heating and impurity removal on a 2L stainless steel high-pressure polymerization reaction kettle, pumping and discharging with high-purity nitrogen for three times, and finally filling trace refined ethylene into the reaction kettle to 0.12MPa. 10mL of 1-hexene comonomer was injected into the reactor. Then, 900mL of purified n-heptane solvent was added sequentially to the reaction vessel, triisobutylaluminum (TIBA) was added as a cocatalyst in an amount of A1/Cr (Cr is the total chromium molar amount) =30, and then 100mL of dehydrated and deoxidized purified n-heptane solvent was added. And (3) regulating the ethylene pressure to 1MPa, and after the temperature in the reactor is constant at 80 ℃, utilizing high-pressure nitrogen to press the catalyst precursor suspension into the polymerization reactor to start the reaction. The instantaneous consumption of monomer ethylene is collected on line in the reaction process and recorded by a computer. After 1h, the reaction was terminated by adding a hydrochloric acid/ethanol mixed solution. After filtration the resulting polymer was dried in a vacuum oven at 60 ℃ for 4 hours, weighed and analyzed.
The catalysts obtained in the above examples and comparative examples were used for ethylene polymerization and the results are shown in Table 1.
Table 1 examples and comparative examples catalysts for ethylene polymerization results
/>
The catalysts used in examples 13-1 to 13-4 were prepared by different processes, and the impregnation loading sequence of the chromium source and the vanadium source and whether or not the pre-reduction activation was performed with the metal organic cocatalyst as shown in Table 1 all had a certain influence on the ethylene polymerization activity of the catalyst. Examples 13-1 and 13-2 demonstrate that pre-reduction activation of the catalyst will result in a significant increase in the catalytic activity of the catalyst. Examples 13-1, 13-3 and 13-4 demonstrate that the catalyst with the stepwise supported chromium source and vanadium source has a better catalytic activity than the catalyst with the co-supported chromium source and vanadium source.
As is clear from examples 13-1 and 14-1 to 14-4, the calcination temperature of the porous inorganic carrier also has a relatively significant effect on the ethylene polymerization activity of the catalyst, and when the calcination temperature is increased from 300 ℃ to 800 ℃, the activity of the catalyst shows a law of increasing first and then decreasing, wherein the activity reaches a maximum value around 600 ℃. This is probably due to the fact that the density of hydroxyl groups on the surface of the catalyst support has a double effect on the chromium source and the vanadium source, on the one hand, hydroxyl groups with too high a density are toxic to the active center, while hydroxyl groups with too low a density will be detrimental to the loading of the chromium source and the vanadium source.
As is clear from examples 13-1, 15-1 to 15-4, and 16-1 to 16-4, the catalyst precursor loading has an optimum range, i.e., the catalyst ethylene polymerization activity tends to gradually rise as the amount of the chromium source or the vanadium source added increases, and at the same time, the catalyst catalytic activity increases to a smaller extent as the amount of the chromium source or the vanadium source added increases. This is probably due to the limited specific surface area of the support, and too high an addition of chromium or vanadium sources would make it difficult to achieve a significant loading of chromium and vanadium sources. On the other hand, the relative addition of the chromium source and the vanadium source has a significant effect on the molecular weight and molecular weight distribution of the polyethylene product, and generally the higher the relative addition of the vanadium source, the higher the molecular weight of the polymer and the narrower the molecular weight distribution. This is caused by the fact that vanadium active centers are better at synthesizing higher molecular weight polymer products.
As is clear from examples 13-1, 17-1 to 17-3, the amount of the alkyl aluminum to be added for the modification of the support also has an optimum range of about 1 to 1.5% by weight based on the weight of A1 of the catalyst when triisobutyl aluminum is used as the modifying component.
As is evident from examples 13-1 and 18-1 to 18-4, the types of the chromium source and the vanadium source also have a certain influence on the catalytic activity of the catalyst. The vanadium chloride is adopted as a vanadium source and is superior to the vanadium bromide; the chromium-dicyclopentadiene with larger volume ligand is used as organic chromium source, the catalytic activity is slightly low, and the molecular weight of the polymer is slightly high. In addition, the type of the alkyl aluminum for modifying the carrier has a certain influence on the catalytic activity of the catalyst, wherein the triisobutyl aluminum with weaker reducibility is better than trimethyl aluminum and triethyl aluminum with stronger reducibility.
As is clear from examples 13-1 and 20-1 to 20-2, the composition, specific surface area, etc. of the porous inorganic carrier have a significant effect on the ethylene polymerization activity of the catalyst, and when a certain amount of metal oxide modified silica gel is used as the carrier, the catalytic activity is higher and the molecular weight of the polymer is lower. Meanwhile, the higher specific surface area of the carrier is beneficial to improving the catalytic activity of the catalyst.
As is evident from examples 13-1 and 21-1 to 21-4, the molar ratio of cocatalyst (activator) to procatalyst has a relatively significant effect on the ethylene polymerization activity and polymerization product of the catalyst and an optimum concentration is present. This is mainly because the activator is insufficient and the metal center is not activated effectively, resulting in lower catalytic activity, while an excessive amount of activator will result in excessive reduction of the metal center to inactive components, resulting in reduced catalytic activity, and therefore a reasonable activator concentration is required to maximize catalytic activity.
As is evident from examples 13-1 and 22-1 to 22-3, the co-catalyst species had a significant effect on the catalyst ethylene polymerization activity and on the polymer molecular weight and molecular weight distribution, wherein triethylaluminum activation was significantly worse, diethylaluminum chloride activation was better, the polymer molecular weight was significantly higher, the methylaluminoxane activation was intermediate, the polymer molecular weight was lower, and the molecular weight distribution was narrower.
As can be seen from examples 13-1 and 23-1 to 23-4, the catalyst system has a positive comonomer effect, i.e.the addition of small amounts of comonomer leads to a significant increase in the catalyst activity. The comonomer introduced at the same time promotes the occurrence of chain transfer reaction, and the molecular weight of the polymer is slightly reduced. The high-temperature nuclear magnetic characterization shows that the comonomer is effectively inserted into the polyethylene chain to form butyl short-chain branches, and the relative content of the butyl short-chain branches in the polymer is gradually increased along with the increase of the concentration of the comonomer, but the increasing amplitude is smaller, so that the catalyst system has an optimal comonomer concentration adding range.
As is evident from examples 13-1 and 24-1 to 24-4, increasing the hydrogen partial pressure significantly decreases the molecular weight of the polymer, and the polymerization activity of the catalyst is also significantly decreased, which indicates that the catalyst system has better hydrogen sensitivity.
As is evident from example 13-1 and comparative examples 7-1 to 7-4, the bimetallic center catalysts of the present invention have significantly higher catalytic activity than the sum of the activities of the corresponding two single metal center catalysts, indicating good catalytic synergy between the two metal centers. Meanwhile, the molecular weight of the polymer synthesized by the vanadium active center in the bimetallic center catalyst is obviously higher, the molecular weight distribution is wider, the molecular weight of the polymer of the organic chromium active center is lower, and the molecular weight distribution is very narrow.
As is clear from examples 13-1 and comparative examples 7-5, modifying the support with the modifier significantly improves the ethylene polymerization activity of the bimetallic catalyst, while modifying the support reduces the molecular weight of the polymer to some extent.
As can be seen from example 13-1 and comparative examples 7-6 (catalysts disclosed in patent CN 103626899A), the supported modified chromium and vanadium bimetallic catalysts of the present invention are superior to those disclosed in patent CN 103626899A.
As is clear from examples 23-1 and comparative examples 8-5, the catalyst obtained by modifying the support with the modifier was used for olefin copolymerization, and the comonomer insertion efficiency was significantly higher. It is evident from examples 8-1 to 8-2 and 8-3 to 8-4 that modification of the support with a modifier significantly increases the comonomer insertion efficiency of the mono-vanadium catalyst but has little effect on the mono-chromium catalyst. This illustrates that the support modifying component improves its overall insertion efficiency primarily by promoting the insertion efficiency of the vanadium-centered comonomer in the bimetallic-centered catalyst.
Of course, the present invention is capable of other various embodiments and its several details are capable of modification and variation in light of the present invention by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (8)
1. The preparation method of the supported double-center catalyst is characterized in that the supported double-center catalyst comprises a carrier and an active component, and comprises the following steps:
Step 1, immersing a carrier in a modifier solution for an immersion reaction, wherein the modifier solution comprises a modifier, and the modifier is an organic aluminum compound;
Step 2, loading the precursor of the active component on the modified carrier, wherein the precursor of the active component comprises an organic chromium source and an inorganic vanadium source, so as to obtain a supported double-center catalyst;
Wherein the organic aluminum compound is at least one of trialkylaluminum AlR 3, dialkylaluminum alkoxide AlR 2 OR, dialkylaluminum halide AlR 2 X, aluminoxane and ethyl aluminum sesquichloride, wherein R is alkyl with 1-12 carbon atoms, and X is halogen;
Wherein the inorganic vanadium source is a vanadium-containing halide; the organic chromium source has the structural formula: crCp 1Cp2, wherein Cp 1 and Cp 2 are independently one of cyclopentadienyl, indenyl and fluorenyl, and Cp 1 is the same or different from Cp 2;
based on the total mass of the supported double-center catalyst, in the supported double-center catalyst, the active component is 0.1 to 8 weight percent of Cr, the V is 0.1 to 10 weight percent of V, and the modifier is 0.1 to 10 weight percent of metal;
the support further comprises a calcination step prior to impregnating the modifier solution to remove water and a portion of the hydroxyl groups from the support surface.
2. The method for preparing the supported double-center catalyst according to claim 1, wherein the modified carrier is loaded with the precursor of the active component in a stepwise manner or simultaneously with the organic chromium source and the inorganic vanadium source.
3. The method for preparing a supported double-center catalyst according to claim 1, wherein the roasting temperature is 200-900 ℃, the heating rate in the roasting process is 0.1-10 ℃/min, and the roasting time is 1-10 h; the loading method of step 2 is impregnation.
4. The method for preparing the supported double-center catalyst according to claim 1, wherein the carrier is at least one of silica, alumina, aluminosilicate, inorganic clay, titania, zirconia, magnesia, iron oxide, tin oxide, and zinc oxide; the specific surface area of the carrier is 100-1000 m 2/g, the pore volume is 0.3-5.0 cm 3/g, and the average pore diameter is 5-50 nm.
5. The method for preparing the supported double-center catalyst according to claim 1, wherein the vanadium source is at least one selected from the group consisting of vanadium trifluoride, vanadium trichloride, vanadium tribromide, vanadium tetrafluoride, vanadium tetrachloride, vanadyl difluoride, vanadyl dichloride, vanadyl dibromide, vanadyl trifluoro oxide, and vanadyl trichlorooxide.
6. A supported double-site catalyst, characterized by being produced by the process for producing a supported double-site catalyst according to any one of claims 1 to 5.
7. A process for the polymerization of olefins, characterized in that the supported double-site catalyst according to claim 6 is used.
8. The method for polymerizing olefins according to claim 7, wherein the step of activating the supported double-center catalyst is performed, and the activating agent is an aluminum alkyl compound.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110895080.1A CN115703853B (en) | 2021-08-03 | 2021-08-03 | Supported double-center catalyst and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110895080.1A CN115703853B (en) | 2021-08-03 | 2021-08-03 | Supported double-center catalyst and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115703853A CN115703853A (en) | 2023-02-17 |
| CN115703853B true CN115703853B (en) | 2024-05-28 |
Family
ID=85178802
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110895080.1A Active CN115703853B (en) | 2021-08-03 | 2021-08-03 | Supported double-center catalyst and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115703853B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117986424B (en) * | 2024-04-02 | 2024-06-25 | 上海卓然工程技术股份有限公司 | Double-center metallocene catalyst and its use in preparing branched double-peak polyethylene |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4263422A (en) * | 1979-12-31 | 1981-04-21 | The Dow Chemical Company | Polymerization of olefins with dual, independently supported catalysts |
| CN101343336A (en) * | 2008-08-20 | 2009-01-14 | 淄博新塑化工有限公司 | Olefin polymerizing catalyst, preparation and use thereof |
| CN103145897A (en) * | 2012-04-20 | 2013-06-12 | 华东理工大学 | Supported metal oxide double-active center ethylene-polymerization catalyst and its preparation method and use |
| WO2013155982A1 (en) * | 2012-04-20 | 2013-10-24 | 华东理工大学 | A supported metal-oxide double-active-center catalyst for ethylene polymerization, preparation method therefor and application thereof |
| CN104448067A (en) * | 2013-09-13 | 2015-03-25 | 中国石油天然气股份有限公司 | Supported organic chromium-vanadium composite catalyst and preparation and application thereof |
| CN109384865A (en) * | 2017-08-02 | 2019-02-26 | 中国石油化工股份有限公司 | Composite reduction chrome alum catalyst and preparation method thereof |
| CN110183556A (en) * | 2019-05-09 | 2019-08-30 | 华南农业大学 | Double Central Composite catalyst of a kind of load-type vanadium, chromium and its preparation method and application |
| CN111087500A (en) * | 2018-10-24 | 2020-05-01 | 中国石油化工股份有限公司 | Chromium-vanadium bimetallic catalyst and application thereof in catalytic synthesis of high-density polyethylene |
-
2021
- 2021-08-03 CN CN202110895080.1A patent/CN115703853B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4263422A (en) * | 1979-12-31 | 1981-04-21 | The Dow Chemical Company | Polymerization of olefins with dual, independently supported catalysts |
| CN101343336A (en) * | 2008-08-20 | 2009-01-14 | 淄博新塑化工有限公司 | Olefin polymerizing catalyst, preparation and use thereof |
| CN103145897A (en) * | 2012-04-20 | 2013-06-12 | 华东理工大学 | Supported metal oxide double-active center ethylene-polymerization catalyst and its preparation method and use |
| WO2013155982A1 (en) * | 2012-04-20 | 2013-10-24 | 华东理工大学 | A supported metal-oxide double-active-center catalyst for ethylene polymerization, preparation method therefor and application thereof |
| CN104448067A (en) * | 2013-09-13 | 2015-03-25 | 中国石油天然气股份有限公司 | Supported organic chromium-vanadium composite catalyst and preparation and application thereof |
| CN109384865A (en) * | 2017-08-02 | 2019-02-26 | 中国石油化工股份有限公司 | Composite reduction chrome alum catalyst and preparation method thereof |
| CN111087500A (en) * | 2018-10-24 | 2020-05-01 | 中国石油化工股份有限公司 | Chromium-vanadium bimetallic catalyst and application thereof in catalytic synthesis of high-density polyethylene |
| CN110183556A (en) * | 2019-05-09 | 2019-08-30 | 华南农业大学 | Double Central Composite catalyst of a kind of load-type vanadium, chromium and its preparation method and application |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115703853A (en) | 2023-02-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9725530B2 (en) | Supported metal oxide double active center polyethylene catalyst, process for preparing the same and use thereof | |
| US6211311B1 (en) | Supported olefin polymerization catalysts | |
| CN110204636B (en) | Supported three-center catalyst and preparation method and application thereof | |
| WO2006063501A1 (en) | Supported non-metallocene olefin polymerization catalyst, and preparation and use thereof | |
| US6790805B2 (en) | Process for the in-situ preparation of single-site transition metal catalysts and polymerization process | |
| CN115703853B (en) | Supported double-center catalyst and preparation method and application thereof | |
| CN115651101B (en) | Supported metallocene catalyst for ethylene polymerization and preparation method thereof | |
| CN115703849B (en) | Supported double-center catalyst and preparation method and application thereof | |
| WO2004029102A1 (en) | Olefin polymerization process | |
| CN115703849A (en) | Supported double-center catalyst and preparation method and application thereof | |
| CN115703852A (en) | Supported chromium-vanadium bimetallic center catalyst and preparation method and application thereof | |
| CN112552437B (en) | Chromium-molybdenum double-center supported catalyst and preparation method and application thereof | |
| CN116410366A (en) | Polyethylene and preparation method thereof | |
| CN116410354A (en) | Supported multi-center catalyst and preparation method thereof | |
| CN112778441B (en) | Supported metallocene catalyst and preparation and application thereof | |
| CN106589178B (en) | Vanadium and metallocene bimetallic catalyst and preparation method thereof | |
| CN112552435A (en) | Double-center supported catalyst and preparation method and application thereof | |
| CN107540767B (en) | Preparation method of bimetallic catalyst for bimodal polyethylene | |
| CN112759679B (en) | Supported non-metallocene catalyst and preparation and application thereof | |
| CN110964140B (en) | In-situ supported non-metallocene catalyst, preparation method and application thereof | |
| KR100466511B1 (en) | High activity olefin polymerization silica supported catalyst | |
| CN110964136B (en) | Composite carrier supported non-metallocene catalyst, preparation method and application thereof | |
| CN110964132B (en) | Composite carrier segmented in-situ supported non-metallocene catalyst and preparation method thereof | |
| CN109485762B (en) | Supported non-metallocene catalyst, preparation method and application thereof | |
| US7094726B2 (en) | Catalyst composition and process for olefin polymerization and copolymerization using supported metallocene catalyst systems |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |