CN114471674A - Carbon nano tube/ZSM-5 molecular sieve compound and synthesis method and application thereof - Google Patents
Carbon nano tube/ZSM-5 molecular sieve compound and synthesis method and application thereof Download PDFInfo
- Publication number
- CN114471674A CN114471674A CN202011159437.1A CN202011159437A CN114471674A CN 114471674 A CN114471674 A CN 114471674A CN 202011159437 A CN202011159437 A CN 202011159437A CN 114471674 A CN114471674 A CN 114471674A
- Authority
- CN
- China
- Prior art keywords
- zsm
- molecular sieve
- hours
- composite
- nano tube
- 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.)
- Pending
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 112
- 239000002041 carbon nanotube Substances 0.000 title claims abstract description 101
- 229910021393 carbon nanotube Inorganic materials 0.000 title claims abstract description 101
- 239000002808 molecular sieve Substances 0.000 title claims abstract description 95
- -1 molecular sieve compound Chemical class 0.000 title claims abstract description 19
- 238000001308 synthesis method Methods 0.000 title claims abstract description 18
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims abstract description 77
- 239000013078 crystal Substances 0.000 claims abstract description 70
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims abstract description 65
- 239000002131 composite material Substances 0.000 claims abstract description 53
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 52
- 238000006243 chemical reaction Methods 0.000 claims abstract description 41
- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical compound CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 claims abstract description 40
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 32
- 238000001035 drying Methods 0.000 claims abstract description 32
- 238000000034 method Methods 0.000 claims abstract description 30
- 239000003054 catalyst Substances 0.000 claims abstract description 24
- 238000005804 alkylation reaction Methods 0.000 claims abstract description 19
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 18
- 230000029936 alkylation Effects 0.000 claims abstract description 17
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 17
- 239000010703 silicon Substances 0.000 claims abstract description 17
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 15
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 15
- 238000002156 mixing Methods 0.000 claims abstract description 15
- 238000010438 heat treatment Methods 0.000 claims abstract description 9
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 8
- 239000003513 alkali Substances 0.000 claims abstract description 7
- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000002253 acid Substances 0.000 claims description 36
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 33
- 238000002425 crystallisation Methods 0.000 claims description 22
- 230000008025 crystallization Effects 0.000 claims description 22
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 19
- VDZOOKBUILJEDG-UHFFFAOYSA-M tetrabutylammonium hydroxide Chemical compound [OH-].CCCC[N+](CCCC)(CCCC)CCCC VDZOOKBUILJEDG-UHFFFAOYSA-M 0.000 claims description 18
- 239000002048 multi walled nanotube Substances 0.000 claims description 16
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 15
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims description 15
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 15
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 claims description 14
- 230000002194 synthesizing effect Effects 0.000 claims description 14
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims description 12
- LPSKDVINWQNWFE-UHFFFAOYSA-M tetrapropylazanium;hydroxide Chemical compound [OH-].CCC[N+](CCC)(CCC)CCC LPSKDVINWQNWFE-UHFFFAOYSA-M 0.000 claims description 12
- 238000003756 stirring Methods 0.000 claims description 11
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 9
- 239000005977 Ethylene Substances 0.000 claims description 9
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 9
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 8
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 8
- 238000010306 acid treatment Methods 0.000 claims description 7
- QUSNBJAOOMFDIB-UHFFFAOYSA-N Ethylamine Chemical compound CCN QUSNBJAOOMFDIB-UHFFFAOYSA-N 0.000 claims description 6
- 229910052593 corundum Inorganic materials 0.000 claims description 6
- 239000000377 silicon dioxide Substances 0.000 claims description 6
- 229910001845 yogo sapphire Inorganic materials 0.000 claims description 6
- 235000006408 oxalic acid Nutrition 0.000 claims description 5
- 229910052681 coesite Inorganic materials 0.000 claims description 4
- 229910052906 cristobalite Inorganic materials 0.000 claims description 4
- 229910052682 stishovite Inorganic materials 0.000 claims description 4
- 229910052905 tridymite Inorganic materials 0.000 claims description 4
- BNGXYYYYKUGPPF-UHFFFAOYSA-M (3-methylphenyl)methyl-triphenylphosphanium;chloride Chemical compound [Cl-].CC1=CC=CC(C[P+](C=2C=CC=CC=2)(C=2C=CC=CC=2)C=2C=CC=CC=2)=C1 BNGXYYYYKUGPPF-UHFFFAOYSA-M 0.000 claims description 2
- 235000019353 potassium silicate Nutrition 0.000 claims description 2
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 2
- 229940073455 tetraethylammonium hydroxide Drugs 0.000 claims description 2
- LRGJRHZIDJQFCL-UHFFFAOYSA-M tetraethylazanium;hydroxide Chemical compound [OH-].CC[N+](CC)(CC)CC LRGJRHZIDJQFCL-UHFFFAOYSA-M 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 8
- 239000012535 impurity Substances 0.000 abstract description 5
- 239000006227 byproduct Substances 0.000 abstract description 4
- 238000002441 X-ray diffraction Methods 0.000 description 46
- 239000000047 product Substances 0.000 description 41
- 230000000052 comparative effect Effects 0.000 description 28
- 238000005406 washing Methods 0.000 description 21
- 230000007935 neutral effect Effects 0.000 description 20
- 239000000243 solution Substances 0.000 description 18
- 238000001816 cooling Methods 0.000 description 16
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 15
- 239000011259 mixed solution Substances 0.000 description 13
- 229910021392 nanocarbon Inorganic materials 0.000 description 8
- 239000000463 material Substances 0.000 description 7
- 239000011148 porous material Substances 0.000 description 7
- 238000005303 weighing Methods 0.000 description 7
- 238000001914 filtration Methods 0.000 description 5
- VNWKTOKETHGBQD-AKLPVKDBSA-N carbane Chemical compound [15CH4] VNWKTOKETHGBQD-AKLPVKDBSA-N 0.000 description 4
- 230000003197 catalytic effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000009792 diffusion process Methods 0.000 description 4
- 239000000376 reactant Substances 0.000 description 4
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 229910021536 Zeolite Inorganic materials 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000006229 carbon black Substances 0.000 description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 3
- 239000002149 hierarchical pore Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000008096 xylene Substances 0.000 description 3
- 239000010457 zeolite Substances 0.000 description 3
- KVNYFPKFSJIPBJ-UHFFFAOYSA-N 1,2-diethylbenzene Chemical compound CCC1=CC=CC=C1CC KVNYFPKFSJIPBJ-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 239000006004 Quartz sand Substances 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000003795 desorption Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 229920000515 polycarbonate Polymers 0.000 description 2
- 239000004417 polycarbonate Substances 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 241000005787 Cistanche Species 0.000 description 1
- 229920000742 Cotton Polymers 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 239000008186 active pharmaceutical agent Substances 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical group [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000005899 aromatization reaction Methods 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000012490 blank solution Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000013064 chemical raw material Substances 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000004587 chromatography analysis Methods 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000003034 coal gas Substances 0.000 description 1
- 239000013065 commercial product Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000006317 isomerization reaction Methods 0.000 description 1
- 238000005360 mashing Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000000696 nitrogen adsorption--desorption isotherm Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 238000004375 physisorption Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- B01J29/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
-
- B01J35/61—
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2/00—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
- C07C2/54—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition of unsaturated hydrocarbons to saturated hydrocarbons or to hydrocarbons containing a six-membered aromatic ring with no unsaturation outside the aromatic ring
- C07C2/64—Addition to a carbon atom of a six-membered aromatic ring
- C07C2/66—Catalytic processes
Abstract
The invention discloses a carbon nano tube/ZSM-5 molecular sieve compound and a synthesis method and application thereof. The carbon nano tube/ZSM-5 molecular sieve compound comprises: the composite comprises a carbon nano tube and a ZSM-5 molecular sieve, wherein the mass content of the carbon nano tube in the composite is 0.05-5.0%. The method comprises the steps of (1) mixing a first silicon source, a structure directing agent, a carbon nano tube and water, and carrying out heat treatment to obtain seed crystals; (2) mixing the seed crystal obtained in the step (1), an aluminum source, an alkali liquor, a second silicon source and water to obtain gel; (3) and (3) crystallizing and drying the gel obtained in the step (2) to obtain the carbon nano tube/ZSM-5 molecular sieve compound. The carbon nano tube/ZSM-5 molecular sieve composite is used as a catalyst in the reaction of preparing ethylbenzene by benzene/ethanol alkylation, and has higher activity and lower generation amount of byproduct impurities.
Description
Technical Field
The invention belongs to the field of molecular sieve synthesis technology and catalysis, and particularly relates to a carbon nanotube/ZSM-5 molecular sieve compound, a synthesis method thereof, and application of the compound in benzene alkylation reaction.
Background
The ZSM-5 molecular sieve is a molecular sieve with high silica-alumina ratio and three-dimensional straight-through pore channels. The crystal structure of ZSM-5 molecular sieve belongs to orthorhombic system, and is formed by connecting silicon (aluminum) oxygen tetrahedron through oxygen bridge bond. ZSM-5 is formed by the intersection of a Z-shaped channel parallel to the axis of the unit cell a and an elliptical channel parallel to the axis of the unit cell b. The unique three-dimensional channel system of the ZSM-5 molecular sieve is favorable for the diffusion of product molecules, and the shape-selective performance is stronger due to the limitation of the size of ten-membered ring channels, so that a multi-branched isomer and a macromolecular product are not easy to form, and carbon deposition is not easy to form in the channel, thereby being favorable for maintaining the catalytic activity. Besides, ZSM-5 has the characteristics of high thermal stability, large specific surface area, adjustable acid center strength and quantity and the like. ZSM-5 has wide application in the fields of petrochemical industry and coal chemical industry, such as alkylation, aromatization, isomerization, cracking and the like, and some of the ZSM-5 has already been industrialized. Therefore, the ZSM-5 molecular sieve has great significance in the petrochemical industry.
The pore channels of the molecular sieve have great influence on the catalytic performance of the molecular sieve, and the reasonable pore channels can shorten the diffusion path of the molecular sieve and improve the mass transfer efficiency, so that the method is one of the key links for preparing a catalyst with higher performance. The traditional molecular sieve has a single pore channel structure, and the diffusion of reactants and products in the reaction process of multi-molecule participation can be limited, so that the conversion rate and the yield of the reaction are influenced. In order to improve or solve the problem, a common method at present is to introduce a hierarchical pore or hierarchical pore molecular sieve to form associated mesopores and micropores in the catalyst, so as to improve the diffusion of the molecules and relieve the carbon deposition of the catalyst. The methods of molecular sieve hierarchical pore can be divided into hard template method, soft template method, crystal growth control method, skeleton atom expanding method, layered molecular sieve pore expanding method and the like.
Ethylbenzene is an important organic chemical raw material, and is mainly used as a raw material for producing styrene in industry. Ethylbenzene is produced primarily by the alkylation of ethylene and benzene. Also ethanol and benzene alkylation is a viable route. The ethanol as the substitute of ethylene can be obtained from comprehensive utilization of agricultural and sideline products, and can also be obtained from coal and natural gas, and has rich sources and low price. The alkylation of benzene/ethanol to ethylbenzene is a very promising route. On the other hand, the benzene alkylation reaction system is a reaction network with coexisting series and parallel side reactions, the reaction system is very complex, and the products, except ethylbenzene and diethylbenzene, also have byproducts, such as toluene and xylene. These by-products can seriously affect the quality of ethylbenzene. CN101450888A discloses a method for synthesizing ethylbenzene from ethanol and benzene, wherein the catalyst comprises: 20 to 45 percent of alumina or silicon oxide, 40 to 70 percent of ZSM-5 with high silica-alumina ratio and 5 to 15 percent of modified component, wherein the modified component is at least one of IIA, IIIA, VA and rare earth metal oxide. The catalyst has the advantages that the conversion rate is not more than 17%, the ethylbenzene selectivity is not more than 97%, and the performance has a larger promotion space, so that increasingly strict requirements of the chemical industry on the catalyst are met.
Therefore, there is an urgent need to develop a benzene alkylation catalyst with high activity and good selectivity.
Disclosure of Invention
The invention provides a carbon nano tube/ZSM-5 molecular sieve composite (CNT/ZSM-5) and a synthesis method and application thereof. The carbon nano tube/ZSM-5 molecular sieve compound is used as a catalyst in the reaction of preparing ethylbenzene by benzene/ethanol alkylation, and has higher activity and better ethylbenzene selectivity.
The inventor of the invention discovers through research that the carbon nano tube is innovatively introduced into a ZSM-5 molecular sieve synthesis system, and by utilizing the unique physical and chemical characteristics of the carbon nano tube, a way is widened for improving the performance of the ZSM-5 molecular sieve, the catalytic potential performance of the ZSM-5 molecular sieve is improved, and higher activity and lower generation amount of byproduct impurities are shown in the reaction of preparing ethylbenzene by benzene/ethanol alkylation.
A first aspect of the present invention provides a carbon nanotube/ZSM-5 molecular sieve composite (CNT/ZSM-5) comprising: the composite comprises a carbon nano tube and a ZSM-5 molecular sieve, wherein the mass content of the carbon nano tube in the composite is 0.05-5.0%, and preferably 0.05-2.0%.
In the above technical solution, the carbon nanotube/ZSM-5 molecular sieve composite includes a framework (i.e., framework aluminum, framework silicon) containing aluminum atoms and silicon atoms, non-framework aluminum, and carbon nanotubes distributed in the bulk phase of the composite, wherein the weight ratio of framework aluminum to non-framework aluminum is (2-10): 1.
in the technical scheme, in the carbon nano tube/ZSM-5 molecular sieve compound, SiO measured by atomic absorption spectrum (ICP)2/Al2O3The molar ratio is 20 to 100, preferably 40 to 95.
In the above technical scheme, in the carbon nanotube/ZSM-5 molecular sieve composite, the amount of the medium strong acid accounts for 25% to 35% of the total acid amount, the amount of the strong acid accounts for 15% to 25% of the total acid amount, preferably, the amount of the medium strong acid accounts for 27% to 34% of the total acid amount, and the amount of the strong acid accounts for 19% to 23% of the total acid amount.
In the technical scheme, the specific surface area of the carbon nanotube/ZSM-5 molecular sieve composite is 400-800 m2Preferably 500 to 700 m/g2/g。
In the above technical scheme, the relative crystallinity of the carbon nanotube/ZSM-5 molecular sieve composite is 80% to 120%, preferably 85% to 110%.
The invention provides a synthesis method of a carbon nano tube/ZSM-5 molecular sieve compound, which comprises the following steps:
(1) mixing a first silicon source, a structure directing agent, a carbon nano tube and water, and carrying out heat treatment to obtain seed crystals;
(2) mixing the seed crystal obtained in the step (1), an aluminum source, an alkali liquor, a second silicon source and water to obtain gel;
(3) crystallizing and drying the gel obtained in the step (2) to obtain the carbon nano tube/ZSM-5 molecular sieve composite.
In the above technical solution, the first silicon source or the second silicon source is independently selected from at least one of water glass, silica sol and silica sol, and more preferably at least one of silica sol and silica sol.
In the above technical solution, in the step (1), the mass ratio of the first silicon source to the water is 0.1 to 10.0, and more preferably 0.2 to 5.0.
In the above technical scheme, in the step (1), the carbon nanotubes are multi-walled carbon nanotubes. The outer diameter of the carbon nanotube is 20 to 100 nm, and more preferably 20 to 50 nm. Multi-walled carbon nanotubes can be prepared by chemical vapor deposition methods.
In the above technical solution, in the step (1), the mass ratio of the carbon nanotubes to water is 0.001 to 0.10, and more preferably 0.01 to 0.05.
In the above technical solution, preferably, the carbon nanotube is pretreated to obtain a pretreated carbon nanotube. And (3) taking the pretreated carbon nano tube as the carbon nano tube raw material in the step (1). The pretreatment refers to acid treatment.
In the above technical solution, in the acid treatment of the carbon nanotube, the acid used may be at least one selected from hydrochloric acid, sulfuric acid, and oxalic acid, and the mass concentration of the acid is 0.05% to 10.0%, preferably 0.1% to 5.0%. The acid treatment conditions include: the treatment temperature is 25-80 ℃, and the treatment time is 4-96 hours.
In the above technical scheme, in the step (1), the structure directing agent is one or a mixture of more of tetraethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide. More preferably at least one of tetrapropylammonium hydroxide and tetrabutylammonium hydroxide. In the step (1), the mass ratio of the structure directing agent to the water is 0.1-10.0.
In the above technical solution, in the step (1), the mixing conditions include: the temperature is 20-40 ℃, and the stirring time is 2-36 hours. The conditions of the heat treatment include: the temperature is 60-80 ℃, and the stirring time is 24-96 hours.
In the technical scheme, in the step (2), the mass ratio of the seed crystal to the water is 0.01-1.0.
In the above technical scheme, in the step (2), the aluminum source is one or a mixture of aluminum sulfate, aluminum chloride and aluminum nitrate. More preferably aluminum sulfate.
In the above technical scheme, in the step (2), the alkali solution is one or a mixture of more of an ammonia water solution, an ethylamine solution and a sodium hydroxide solution, and the ammonia water solution is further preferred.
In the technical scheme, in the step (2), the mass ratios of the aluminum source, the alkali liquor, the second silicon source and the water are respectively 0.005-0.10, 0.02-2.0 and 0.05-5.0; preferably, the second silicon source is SiO2Calculated by Al as the aluminum source2O3Meter, SiO2/Al2O3The molar ratio is 20 to 100.
In the above technical solution, in the step (2), the mixing conditions include: the temperature is 20-60 ℃, and the stirring time is 1-12 hours.
In the above technical solution, in the step (3), the crystallization conditions include: the crystallization temperature is 160-200 ℃, and the crystallization time is 10-36 hours.
In the above technical solution, in the step (3), after the crystallization is finished, before the drying, there may be a conventional step such as separation, washing, etc. The drying conditions include: the drying temperature is 100-150 ℃, and the drying time is 0.5-16 hours, preferably 2-12 hours. The drying equipment may be an oven or the like as is conventional in the art.
The third aspect of the invention provides an application of the carbon nano tube/ZSM-5 molecular sieve compound as a catalyst in a reaction for preparing ethylbenzene by benzene/ethanol alkylation.
In the technical scheme, the carbon nano tube/ZSM-5 molecular sieve can be prepared into the catalyst by adopting an extrusion molding method, the length of the catalyst can be 3.0-10.0 mm of a cylinder, the cross section of the cylinder is circular, square, clover-shaped or star-shaped, and the maximum radial dimension of the cross section is 0.8-3.0 mm.
In the technical scheme, the reaction conditions for preparing ethylbenzene by benzene/ethanol alkylation are as follows: the reaction temperature is 300-350 ℃, the reaction pressure is 0-0.5 MPa, the benzene/ethanol molar ratio is 4-8, and the mass space velocity of ethanol is 0.2-2.0 h-1。
The fourth aspect of the invention provides an application of the carbon nano tube/ZSM-5 molecular sieve compound as a catalyst in a reaction of preparing ethylbenzene by benzene/ethylene alkylation.
In the technical scheme, the carbon nanotube/ZSM-5 molecular sieve can be prepared into the catalyst by adopting an extrusion molding method, the length of the catalyst can be a cylinder of 3-10 mm, the cross section of the cylinder is circular, square, clover-shaped or star-shaped, and the maximum radial dimension of the cross section is 0.8-3.0 mm.
In the technical scheme, the reaction conditions for preparing ethylbenzene by benzene/ethylene alkylation are as follows: the reaction temperature is 300-350 ℃, the reaction pressure is 0-0.5 MPa, the benzene/ethylene molar ratio is 4-8, and the ethylene mass space velocity is 0.2-1.0 h-1。
The carbon nano tube/ZSM-5 molecular sieve compound has the following advantages:
1. the carbon nano tube/ZSM-5 molecular sieve compound has more medium-strong acid amount and less strong acid amount, and compared with the ZSM-5 molecular sieve, the specific surface area and the pore structure are not obviously changed after the carbon nano tube is introduced.
2. The method for synthesizing the carbon nano tube/ZSM-5 molecular sieve compound realizes the regulation and control of the acidity of the molecular sieve without influencing the pore structure of the molecular sieve by introducing a small amount of carbon nano tubes.
3. When the carbon nano tube/ZSM-5 molecular sieve composite is used as a catalyst in the reaction of preparing ethylbenzene by benzene/ethanol (or ethylene) alkylation, the carbon nano tube/ZSM-5 molecular sieve composite has higher activity, lower xylene impurity generation amount and stronger comprehensive reaction performance.
4. According to the method for synthesizing the carbon nanotube/ZSM-5 molecular sieve compound, the carbon nanotube is subjected to acid treatment, oxygen-containing functional groups on the surface of the carbon nanotube can be regulated and controlled, and the distribution of acidity of the carbon nanotube/ZSM-5 compound molecular sieve can be regulated and controlled, so that the carbon nanotube/ZSM-5 compound molecular sieve compound has better activity and selectivity when being used in a reaction for preparing ethylbenzene by benzene/ethanol (or ethylene) alkylation.
Drawings
FIG. 1 is an XRD pattern of a carbon nanotube/ZSM-5 molecular sieve composite obtained in example 1;
FIG. 2 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 2;
FIG. 3 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 3;
FIG. 4 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 4;
FIG. 5 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 5;
FIG. 6 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 6;
FIG. 7 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 7;
FIG. 8 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 8;
FIG. 9 is an XRD pattern of the ZSM-5 molecular sieve obtained in comparative example 1;
FIG. 10 is an XRD pattern of the ZSM-5 molecular sieve obtained in comparative example 2;
FIG. 11 is an XRD pattern of the ZSM-5 molecular sieve obtained in comparative example 3;
FIG. 12 is an XRD pattern of the ZSM-5 molecular sieve obtained in comparative example 4;
FIG. 13 is an XRD pattern of the carbon nanotube/ZSM-5 molecular sieve composite obtained in comparative example 5;
FIG. 14 shows NH of the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 13-a TPD map;
FIG. 15 shows NH of ZSM-5 molecular sieve obtained in comparative example 13-a TPD map;
FIG. 16 is a graph showing the comparison between the catalytic activity and the amount of impurities generated when the carbon nanotube/ZSM-5 molecular sieve composite obtained in example 1, example 2, example 3 and comparative example 5 and the ZSM-5 molecular sieve obtained in comparative example 1 were used as catalysts, respectively.
Detailed Description
The technical solutions of the present invention will be described in detail below in order to clearly understand the technical features, objects, and advantages of the present invention, but the present invention is not limited to the practical scope of the present invention.
The test method of the invention is as follows:
(1) relative crystallinity calculation method. The relative crystallinity is obtained by comparing the peak area of the sample at 22.5-25 degrees with the standard peak area of the commercial product ZSM-5, and the calculation formula is as follows:
R＝AP/AR(formula I)
Wherein R is the relative crystallinity, APIs the peak area of the sample to be measured at 22.5-25 DEG, ARIs the peak area of the standard sample at 22.5-25 deg.
(2) X-ray diffraction method. The phase (XRD) of the sample was determined using a Bruker model D8X-ray powder diffractometer (Cu ka,
) And measuring by a scanning diffractometer. Cu target, graphite monochromatic filter, slit SS/DS 1 °, RS 0.15mm, operating voltage: 40KV, current: 30 mA.
(3) The specific surface area is measured by adopting a nitrogen adsorption-desorption isotherm. The specific operation is as follows: the instrument model used was Micromeritics ASAP 2020 and the test temperature was 196 ℃ below zero. Before the nitrogen physisorption, the sample was degassed at 330 ℃ under 1.33Pa for 4 hours. The total specific surface area was calculated according to the BET (Brunauer-Emmett-Teller) equation.
(4) Acid strength desorption (NH) by ammonia-temperature programming3TPD) analysis method, in particular by: and tabletting, mashing and screening the molecular sieve sample, and drying 20-40 mesh particles for later use to obtain a sample to be detected. During the experiment, 150 mg of dry sample to be tested is accurately weighed and put into a quartz tube. The lower part of the zeolite bed layer is supported by a quartz sand bed layer, and the upper part of the zeolite bed layer is covered by the quartz sand bed layer, so that the zeolite bed layer is positioned at the position of a thermocouple. Heating the sample to 550 ℃ in a helium atmosphere, activating for 2 hours, cooling to room temperature, adsorbing 10% ammonia gas for 30 minutes, heating to 100 ℃ for constant, heating to 650 ℃ at a heating rate of 10 ℃/minute when the baseline is stable, and collecting an ammonia gas desorption signal. Total acid content by para-NH3The TPD peak area is integrated. The contents of weak acid, medium strong acid and strong acid are determined by the content of para-NH3After TPD is subjected to peak separation, the peak position of weak acid is about 200 ℃, the peak position of medium strong acid is about 330 ℃ and the peak position of strong acid is about 410 ℃ according to the percentage of the peak area.
(5) Measurement of SiO of catalyst by atomic absorption Spectroscopy (ICP)2/Al2O3The molar ratio. 100 mg of the ground sample was weighed into a crucible, and 1 g of hydrogen hydroxide was addedThe sodium is melted at 750 ℃ for 15 minutes, the minced cistanche is neutralized by adding hydrochloric acid after being not cooled, and then the solution is transferred to a 100 ml volumetric flask for constant volume and diluted by 10 times. Measuring by using an ICP spectrometer, comparing with the blank solution result, and calculating to obtain the SiO of the molecular sieve or the compound2/Al2O3The molar ratio.
[ example 1 ]
This example provides a method for synthesizing a carbon nanotube/ZSM-5 molecular sieve composite, which includes the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide, 0.15 g of multi-walled carbon nanotubes (the outer diameter is 20 nanometers) and 15 g of water are weighed and mixed, and stirred for 24 hours at 25 ℃ to obtain a mixed solution A. The mixture A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: weighing 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO)2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: and (3) placing the gel A in a reaction kettle, crystallizing at 170 ℃ for 24 hours, cooling to room temperature, centrifugally washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-1, wherein the properties of the product CNT/ZSM-5-1 are shown in table 1, the XRD pattern of the product CNT/ZSM-5-1 is shown in figure 1, the sample obtained in example 1 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 2 ]
The embodiment provides a method for synthesizing a nano carbon/ZSM-5 molecular sieve compound, which comprises the following steps:
(1) pretreating the carbon nano tube: weighing 1 g of multi-walled carbon nanotube (with the outer diameter of 20 nanometers), 0.5 g of hydrochloric acid (with the mass concentration of 37 percent) and 99.5 g of water, mixing, stirring for 4 hours at 25 ℃, filtering and washing the carbon nanotube to be neutral, and drying for 12 hours at the temperature of 150 ℃ to obtain the modified carbon nanotube.
Preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide, 0.15 g of the modified carbon nano tube and 15 g of water are weighed and mixed, and stirred for 24 hours at 25 ℃ to obtain mixed liquid A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-2, wherein the properties of the product CNT/ZSM-5-2 are shown in Table 1, the XRD diagram of the product is shown in figure 2, and as can be seen from figure 2, the sample obtained in example 2 is consistent with the standard XRD diagram of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
Comparative example 1
This comparative example is a reference for examples 1 and 2, and the synthesis method includes the following steps without adding carbon nanotubes:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain a sample CNT/ZSM-5-C1, wherein the properties of the sample are shown in Table 1, the XRD pattern of the sample is shown in figure 9, the properties of the sample can be seen from figure 9, and the sample obtained in comparative example 1 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
NH of CNT/ZSM-5-1 obtained in example 13FIG. 14 shows TPD, in which CNT/ZSM-5-1 has a smaller amount of strong acid than CNT/ZSM-5-C1 (obtained in comparative example 1) which is a reference agent without carbon nanotubes, and part of the strong acid is converted into a medium strong acid (see FIG. 14, FIG. 15, Table)1). Compared with CNT/ZSM-5-C1, the ratio of the strong acid peak area in the CNT/ZSM-5-1 composite is increased to 30.7% from the original 17.9%, while the strong acid peak area is reduced to 21.0% from the original 34.5%, and the weak acid percentage is not obviously changed.
[ example 3 ]
The embodiment provides a method for synthesizing a nanocarbon/molecular sieve composite molecular sieve material, which comprises the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide, 0.15 g of multi-walled carbon nanotubes (the outer diameter is 20 nm) and 15 g of water are weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 3.5 g of sodium hydroxide, 41 g of water, 5.4 g of white carbon black and 4 g of seed crystal are weighed and mixed, and stirred for 1.5 hours at the temperature of 25 ℃ to obtain gel A.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-3, wherein the properties of the product CNT/ZSM-5-3 are shown in Table 1, the XRD pattern of the product is shown in figure 3, the properties of the product can be seen in figure 3, the sample obtained in example 3 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 4 ]
The embodiment provides a method for synthesizing a nanocarbon/molecular sieve composite molecular sieve material, which comprises the following steps:
(1) pretreating the carbon nano tube: weighing 1 g of multi-walled carbon nanotube (with the outer diameter of 20 nanometers), 5g of oxalic acid and 95g of water, mixing, stirring at 25 ℃ for 24 hours, filtering and washing the carbon nanotube to be neutral, and drying at 150 ℃ for 12 hours to obtain the modified carbon nanotube.
Preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide, 0.15 g of modified multi-walled carbon nanotubes and 15 g of water are weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 3.5 g of sodium hydroxide, 41 g of water, 5.4 g of white carbon black and 4 g of seed crystal are weighed and mixed, and stirred for 1.5 hours at the temperature of 25 ℃ to obtain gel A.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-4, wherein the properties of the product CNT/ZSM-5-4 are shown in Table 1, the XRD pattern of the product is shown in figure 4, the properties of the product can be seen in figure 4, and the sample obtained in example 4 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
Comparative example 2
This comparative example, which is a reference for examples 3 and 4, was synthesized without adding carbon nanotubes, and the synthesis method thereof included the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 3.5 g of sodium hydroxide, 41 g of water, 5.4 g of white carbon black and 4 g of seed crystal are weighed and mixed, and stirred for 1.5 hours at the temperature of 25 ℃ to obtain gel A.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain a sample CNT/ZSM-5-C2, wherein the properties of the sample are shown in Table 1, the XRD pattern of the sample is shown in figure 10, the properties of the sample can be seen in figure 10, and the sample obtained in comparative example 2 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 5 ]
The embodiment provides a method for synthesizing a nanocarbon/molecular sieve composite molecular sieve material, which comprises the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 38 g of tetrabutylammonium hydroxide, 0.2 g of multi-walled carbon nanotubes (20 nm in outer diameter) and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-5, wherein the properties of the product CNT/ZSM-5-5 are shown in Table 1, the XRD pattern of the product is shown in figure 5, the properties of the product are shown in figure 9, and the sample obtained in example 2 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity and has no obvious peak of other mixed crystals.
[ example 6 ] A method for producing a polycarbonate
The embodiment provides a method for synthesizing a nanocarbon/molecular sieve composite molecular sieve material, which comprises the following steps:
(1) pretreating the carbon nano tube: weighing 1 g of multi-wall carbon nano tube (the outer diameter is 20 nm), 5g of oxalic acid and 95g of water, mixing, stirring for 24 hours at 25 ℃, filtering and washing the carbon nano tube to be neutral, and drying for 12 hours at the temperature of 120-180 ℃ to obtain the modified carbon nano tube.
Preparing seed crystals: 20 g of ethyl orthosilicate, 38 g of tetrabutylammonium hydroxide, 0.2 g of the above-mentioned modified carbon nanotubes and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-6, wherein the properties of the product CNT/ZSM-5-6 are shown in Table 1, an XRD (X-ray diffraction) diagram is shown in figure 6, as can be seen from figure 6, and a sample obtained in example 6 is consistent with a ZSM-5 standard XRD diagram in peak position and intensity and has no obvious peak of other mixed crystals.
Comparative example 3
This comparative example, which is a reference for examples 5 and 6, was synthesized without adding carbon nanotubes, and the synthesis method included the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 38 g of tetrabutylammonium hydroxide and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain a sample CNT/ZSM-5-C3, wherein the properties of the sample are shown in Table 1, the XRD pattern of the sample is shown in figure 11, the properties of the sample can be seen in figure 11, and the sample obtained in comparative example 3 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 7 ]
The embodiment provides a method for synthesizing a nanocarbon/molecular sieve composite molecular sieve material, which comprises the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 38 g of tetrabutylammonium hydroxide, 0.2 g of multi-walled carbon nanotubes (20 nm in outer diameter) and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.31 g of aluminum chloride, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-7, wherein the properties of the product CNT/ZSM-5-7 are shown in Table 1, the XRD pattern of the product is shown in figure 7, the properties of the product can be seen in figure 7, the sample obtained in example 7 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 8 ]
The embodiment provides a method for synthesizing a nanocarbon/molecular sieve composite molecular sieve material, which comprises the following steps:
(1) pretreating the carbon nano tube: weighing 1 g of multi-walled carbon nanotube (with the outer diameter of 20 nanometers), 5g of oxalic acid and 95g of water, mixing, stirring at 25 ℃ for 24 hours, filtering and washing the carbon nanotube to be neutral, and drying at 150 ℃ for 12 hours to obtain the modified carbon nanotube.
Preparing seed crystals: 20 g of ethyl orthosilicate, 38 g of tetrabutylammonium hydroxide, 0.2 g of modified multiwall carbon nanotubes and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.31 g of aluminum chloride, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%) and 4 g of seed crystal were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-8, wherein the properties of the product CNT/ZSM-5-8 are shown in Table 1, the XRD pattern of the product is shown in figure 8, the properties of the product can be seen in figure 8, and the sample obtained in example 8 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
Comparative example 4
This comparative example, which is a reference for examples 7 and 8, was synthesized without adding carbon nanotubes, and the synthesis method included the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 38 g of tetrabutylammonium hydroxide and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.31 g of aluminum chloride, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed245 percent by mass) and 4 grams of seed crystal are mixed inStirring was carried out at 25 ℃ for 1.5 hours to obtain gel A.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 170 ℃ for 24 hours, cooling to room temperature, centrifuging and washing to be neutral, and drying at 150 ℃ for 6 hours to obtain a sample CNT/ZSM-5-C4, wherein the properties of the sample are shown in Table 1, the XRD pattern of the sample is shown in figure 12, the properties of the sample can be seen from figure 12, and the sample obtained in comparative example 4 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
Comparative example 5
This comparative example added carbon nanotubes as a hard template and did not bake, leaving the carbon nanotubes. The synthesis method comprises the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide and 15 g of water were weighed and mixed, and stirred at 25 ℃ for 24 hours to obtain a mixed solution A. The mixture A was stirred at 70 ℃ for 72 hours to obtain seed crystals.
(2) Preparing gel: 0.4 g of aluminum sulfate, 11 g of ammonia water, 34 g of water and 12 g of silica Sol (SiO) are weighed2Mass content 45%), 4 g of seed crystal and 4 g of multi-walled carbon nanotube (outer diameter 20 nm) were mixed and stirred at 25 ℃ for 1.5 hours to obtain gel a.
(3) And (3) crystallization: and (3) placing the gel A in a reaction kettle, crystallizing at 170 ℃ for 24 hours, cooling to room temperature, centrifugally washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-C5, wherein the properties of the product CNT/ZSM-5-C5 are shown in Table 1, the XRD pattern of the product is shown in figure 13, as can be seen from figure 13, and the sample obtained in the comparative example 5 is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity and has no obvious peak of other mixed crystals.
[ example 9 ]
The embodiment provides a method for synthesizing a carbon nano tube/ZSM-5 molecular sieve composite, which comprises the following steps:
(1) preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide, 1 g of multi-walled carbon nanotubes (the outer diameter is 20 nanometers) and 100 g of water are weighed and mixed, and the mixture is stirred for 36 hours at the temperature of 20 ℃ to obtain a mixed solution A. The mixture A was stirred at 60 ℃ for 96 hours to obtain seed crystals.
(2) Preparing gel: 0.6 g of sulfuric acid, 11 g of ammonia water, 6 g of water and 18 g of silica Sol (SiO) are weighed2 Mass content 30%) and 12 g of seed crystal were mixed and stirred at 60 ℃ for 1 hour to obtain gel a.
(3) And (3) crystallization: and (3) placing the gel A in a reaction kettle, crystallizing at 165 ℃ for 36 hours, cooling to room temperature, centrifugally washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-9, wherein the properties of the product CNT/ZSM-5-9 are shown in Table 1. The XRD pattern is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 10 ]
The embodiment provides a method for synthesizing a nanocarbon/ZSM-5 molecular sieve composite, which comprises the following steps:
(1) pretreating the carbon nano tube: weighing 1 g of multi-walled carbon nanotube (with the outer diameter of 20 nanometers), 5g of sulfuric acid (with the mass concentration of 98 percent) and 95g of water, mixing, stirring for 4 hours at 80 ℃, filtering and washing the carbon nanotube to be neutral, and drying for 12 hours at the temperature of 150 ℃ to obtain the modified carbon nanotube.
Preparing seed crystals: 20 g of ethyl orthosilicate, 30 g of tetrapropylammonium hydroxide, 0.1 g of the modified carbon nano tube and 5g of water are weighed and mixed, and stirred for 4 hours at 40 ℃ to obtain mixed liquid A. A was stirred at 80 ℃ for 24 hours to obtain seed crystals.
(2) Preparing gel: 0.26 g of aluminum chloride, 5.1 g of ethylamine solution, 34 g of water and 12 g of silica Sol (SiO)2Mass content 45%) and 2 g of seed crystals were mixed and stirred at 25 ℃ for 12 hours to obtain gel a.
(3) And (3) crystallization: crystallizing the gel A in a reaction kettle at 185 ℃ for 12 hours, then cooling to room temperature, centrifugally washing to be neutral, and drying at 150 ℃ for 6 hours to obtain the product CNT/ZSM-5-10, wherein the properties of the product are shown in Table 1. The XRD pattern is consistent with the standard XRD pattern of ZSM-5 in peak position and intensity, and no obvious peak of other mixed crystals appears.
[ example 11 ]
The catalyst evaluation was carried out on a fixed-bed pulse microdevice. The specific operation is as follows: precisely weighing 20 mg of CNT/ZSM-5-1 as a catalyst, and filling the catalyst into a quartz glass tube special for a fixed bed-pulse micro device, wherein a layer of quartz cotton is respectively paved on the upper part and the lower part of the CNT/ZSM-5-1 catalyst for supporting and covering. Quantitatively absorbing the reactant by a micro-injector, injecting the reactant into the reaction tube through an injection port, and analyzing and detecting the product by using gas chromatography. The reaction temperature is 350 ℃, the reactant is benzene/ethanol mixed liquor, the molar ratio is 6:1, and the injection amount is 1 microliter; the chromatography model is Agilent 7890B, and the detector used is a flame ion detector. The result of the CNT/ZSM-5-1 reaction is shown in FIG. 16.
[ example 12 ] A method for producing a polycarbonate
In comparison with example 11, CNT/ZSM-5-1 was replaced with CNT/ZSM-5-2, and the results are shown in FIG. 16.
[ example 13 ]
In comparison with example 11, CNT/ZSM-5-1 was replaced with CNT/ZSM-5-3, and the results are shown in FIG. 16.
Comparative example 6
In contrast to example 11, CNT/ZSM-5-1 was replaced with CNT/ZSM-5-C1, and the results are shown in FIG. 16.
Comparative example 7
In contrast to example 11, CNT/ZSM-5-1 was replaced with CNT/ZSM-5-C5, and the results are shown in FIG. 16.
As can be seen from FIG. 16, in the benzene/ethanol alkylation to ethylbenzene reaction, CNT/ZSM-5-1, CNT/ZSM-5-2 and CNT/ZSM-5-3 all had higher activity and lower impurity formation than CNT/ZSM-5-C1 (FIG. 16). It can also be seen from FIG. 16 that since the hard template method requires a large amount of carbon nanotubes for preparing the composite, the activity is significantly lower than that of CNT/ZSM-5-1 of example 1 and CNT/ZSM-5-C1 of comparative example 1, if not removed from direct use, compared to CNT/ZSM-5-C5 (obtained by comparative example 5) which is added without calcination by means of the hard template. On the other hand, CNT/ZSM-5-2, although having lower xylene production compared to CNT/ZSM-5-1, suggests that modification of carbon nanotubes can further modulate the acidity and performance of the composite catalyst.
TABLE 1
It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.
Claims (14)
1. A carbon nanotube/ZSM-5 molecular sieve composite, comprising: the composite comprises a carbon nano tube and a ZSM-5 molecular sieve, wherein the mass content of the carbon nano tube in the composite is 0.05-5.0%, and preferably 0.05-2.0%.
2. The composite of claim 1, wherein the carbon nanotube/ZSM-5 molecular sieve composite has carbon nanotubes distributed in the bulk phase of the composite.
3. The composite of claim 1, wherein the weight ratio of framework aluminum to non-framework aluminum in the carbon nanotube/ZSM-5 molecular sieve composite is 2-10: 1; SiO 22/Al2O3The molar ratio of (A) is 20 to 100, preferably 40 to 95.
4. The composite of claim 1, wherein the amount of the medium strong acid accounts for 25-35% of the total acid amount, the amount of the strong acid accounts for 15-25% of the total acid amount, preferably, the amount of the medium strong acid accounts for 27-34% of the total acid amount, and the amount of the strong acid accounts for 19-23% of the total acid amount in the carbon nanotube/ZSM-5 molecular sieve composite.
5. The composite of claim 1, wherein the carbon nanotube/ZSM-5 molecular sieve composite has a specific surface area of 400 to 800m2Preferably 500 to 700 m/g2/g。
6. A method for synthesizing a carbon nanotube/ZSM-5 molecular sieve composite comprises the following steps:
(1) mixing a first silicon source, a structure directing agent, a carbon nano tube and water, and carrying out heat treatment to obtain seed crystals;
(2) mixing the seed crystal obtained in the step (1), an aluminum source, an alkali liquor, a second silicon source and water to obtain gel;
(3) and (3) crystallizing and drying the gel obtained in the step (2) to obtain the carbon nano tube/ZSM-5 molecular sieve compound.
7. The synthesis method according to claim 6, wherein the first silicon source or the second silicon source is independently selected from at least one of water glass, silica white and silica sol, preferably at least one of silica sol or silica white; in the step (2), the aluminum source is one or a mixture of more of aluminum sulfate, aluminum chloride and aluminum nitrate, preferably aluminum sulfate; in the step (2), the alkali liquor is one or a mixture of more of an ammonia water solution, an ethylamine solution and a sodium hydroxide solution, and the ammonia water solution is preferred.
8. The synthesis method according to claim 6, wherein in step (1), the mass ratio of the first silicon source to water is 0.1-10.0, preferably 0.2-5.0.
9. The synthesis method according to claim 6, wherein the carbon nanotubes are multi-walled carbon nanotubes, and the outer diameter of the carbon nanotubes is 20 to 100 nm, preferably 20 to 50 nm; in the step (1), the mass ratio of the carbon nanotubes to the water is 0.001 to 0.10, preferably 0.01 to 0.05.
10. The synthesis method according to claim 6, wherein the carbon nanotubes are pretreated to obtain pretreated carbon nanotubes, and then the step (1) is performed; the pretreatment is acid treatment;
preferably, in the acid treatment of the carbon nanotube, the acid used is at least one selected from hydrochloric acid, sulfuric acid and oxalic acid, and the mass concentration of the acid is 0.05-10.0%, preferably 0.1-5.0%; the acid treatment conditions include: the treatment temperature is 25-80 ℃, and the treatment time is 4-96 hours.
11. The synthesis method according to claim 6, wherein in the step (1), the structure-directing agent is one or more of tetraethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide; in the step (1), the mass ratio of the structure directing agent to the water is 0.1-10.0.
12. The method of claim 6, wherein in step (1), the mixing conditions comprise: the temperature is 20-40 ℃, and the stirring time is 2-36 hours; the conditions of the heat treatment include: the temperature is 60-80 ℃, and the stirring time is 24-96 hours.
13. The synthesis method according to claim 6, wherein in the step (2), the mass ratio of the seed crystal to the water is 0.01 to 1.0;
and/or in the step (2), the mass ratios of the aluminum source, the alkali liquor, the second silicon source and the water are respectively 0.005-0.10, 0.02-2.0 and 0.05-5.0; preferably, the second silicon source is SiO2Calculated by Al as the aluminum source2O3Meter, SiO2/Al2O3The molar ratio is 20 to 100.
And/or, in the step (2), the mixing conditions comprise: the temperature is 20-60 ℃, and the stirring time is 1-12 hours;
and/or, in the step (3), the crystallization conditions comprise: the crystallization temperature is 160-200 ℃, and the crystallization time is 10-36 hours;
and/or, the drying conditions include: the drying temperature is 100-150 ℃, and the drying time is 0.5-16 hours, preferably 2-12 hours.
14. The use of the carbon nanotube/ZSM-5 molecular sieve composite of any of claims 1-5 or the carbon nanotube/ZSM-5 molecular sieve composite synthesized by the synthesis method of any of claims 6-13 as a catalyst in a reaction for preparing ethylbenzene by benzene/ethanol alkylation or a reaction for preparing ethylbenzene by benzene/ethylene alkylation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011159437.1A CN114471674A (en) | 2020-10-26 | 2020-10-26 | Carbon nano tube/ZSM-5 molecular sieve compound and synthesis method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011159437.1A CN114471674A (en) | 2020-10-26 | 2020-10-26 | Carbon nano tube/ZSM-5 molecular sieve compound and synthesis method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114471674A true CN114471674A (en) | 2022-05-13 |
Family
ID=81471156
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011159437.1A Pending CN114471674A (en) | 2020-10-26 | 2020-10-26 | Carbon nano tube/ZSM-5 molecular sieve compound and synthesis method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114471674A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116474747A (en) * | 2023-03-24 | 2023-07-25 | 北京师范大学珠海校区 | Lanthanum-loaded iron carbon nanotube composite molecular sieve film and preparation method and application thereof |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030116503A1 (en) * | 2001-12-21 | 2003-06-26 | Yong Wang | Carbon nanotube-containing structures, methods of making, and processes using same |
| CN101224432A (en) * | 2008-02-03 | 2008-07-23 | 山东省科学院能源研究所 | Integral supported carbon molecular sieve catalyst, preparing method and applications thereof |
| CN101406851A (en) * | 2004-11-04 | 2009-04-15 | 三星Sdi株式会社 | Mesoporous carbon composite containing carbon nanotube |
| CN101941716A (en) * | 2010-07-07 | 2011-01-12 | 中国科学院广州能源研究所 | Preparation method for ZSM-5 molecular sieve membrane with high hydrophobicity |
| US20120058889A1 (en) * | 2009-03-04 | 2012-03-08 | Hidekazu Nishino | Composition containing carbon nanotubes, catalyst for producing carbon nanotubes, and aqueous dispersion of carbon nanotubes |
| CN103449474A (en) * | 2012-06-01 | 2013-12-18 | 中国石油化工股份有限公司 | Phosphorus-containing ZSM-5 molecular sieve membrane and preparation method thereof |
| CN104646057A (en) * | 2013-11-19 | 2015-05-27 | 中国科学院金属研究所 | Polyacid/nano-carbon-hybridized solid acid catalyst, preparation method and application thereof |
| CN105399110A (en) * | 2015-12-24 | 2016-03-16 | 中山大学惠州研究院 | Synthetic method of porous ZSM-5 molecular sieve |
| CN109485065A (en) * | 2017-09-09 | 2019-03-19 | 中国石油化工股份有限公司 | A kind of multistage porous molecular sieve and preparation method thereof |
| CN110882715A (en) * | 2018-09-07 | 2020-03-17 | 中国科学院大连化学物理研究所 | Preparation method and application of molecular sieve catalyst |
| CN111111758A (en) * | 2018-10-30 | 2020-05-08 | 中国石油化工股份有限公司 | Catalyst for preparing toluene and/or xylene by liquid-phase methylation and preparation method thereof |
-
2020
- 2020-10-26 CN CN202011159437.1A patent/CN114471674A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030116503A1 (en) * | 2001-12-21 | 2003-06-26 | Yong Wang | Carbon nanotube-containing structures, methods of making, and processes using same |
| CN101406851A (en) * | 2004-11-04 | 2009-04-15 | 三星Sdi株式会社 | Mesoporous carbon composite containing carbon nanotube |
| CN101224432A (en) * | 2008-02-03 | 2008-07-23 | 山东省科学院能源研究所 | Integral supported carbon molecular sieve catalyst, preparing method and applications thereof |
| US20120058889A1 (en) * | 2009-03-04 | 2012-03-08 | Hidekazu Nishino | Composition containing carbon nanotubes, catalyst for producing carbon nanotubes, and aqueous dispersion of carbon nanotubes |
| CN101941716A (en) * | 2010-07-07 | 2011-01-12 | 中国科学院广州能源研究所 | Preparation method for ZSM-5 molecular sieve membrane with high hydrophobicity |
| CN103449474A (en) * | 2012-06-01 | 2013-12-18 | 中国石油化工股份有限公司 | Phosphorus-containing ZSM-5 molecular sieve membrane and preparation method thereof |
| CN104646057A (en) * | 2013-11-19 | 2015-05-27 | 中国科学院金属研究所 | Polyacid/nano-carbon-hybridized solid acid catalyst, preparation method and application thereof |
| CN105399110A (en) * | 2015-12-24 | 2016-03-16 | 中山大学惠州研究院 | Synthetic method of porous ZSM-5 molecular sieve |
| CN109485065A (en) * | 2017-09-09 | 2019-03-19 | 中国石油化工股份有限公司 | A kind of multistage porous molecular sieve and preparation method thereof |
| CN110882715A (en) * | 2018-09-07 | 2020-03-17 | 中国科学院大连化学物理研究所 | Preparation method and application of molecular sieve catalyst |
| CN111111758A (en) * | 2018-10-30 | 2020-05-08 | 中国石油化工股份有限公司 | Catalyst for preparing toluene and/or xylene by liquid-phase methylation and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 王冉 等: "多级孔纳米ZSM-5分子筛的制备及其催化芳构化性能研究", 《化工管理》, no. 2017, pages 83 - 85 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116474747A (en) * | 2023-03-24 | 2023-07-25 | 北京师范大学珠海校区 | Lanthanum-loaded iron carbon nanotube composite molecular sieve film and preparation method and application thereof |
| CN116474747B (en) * | 2023-03-24 | 2023-10-31 | 北京师范大学珠海校区 | Lanthanum-loaded iron carbon nanotube composite molecular sieve film and preparation method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Schmidt et al. | Improved catalytic performance of hierarchical ZSM-5 synthesized by desilication with surfactants | |
| Izadbakhsh et al. | Effect of SAPO-34's composition on its physico-chemical properties and deactivation in MTO process | |
| US10160656B2 (en) | Organotemplate-free solid-state synthetic method for zeolite molecular sieves | |
| US7485766B2 (en) | Oxygenate conversion using molecular sieve SSZ-74 | |
| Chu et al. | An unusual hierarchical ZSM-5 microsphere with good catalytic performance in methane dehydroaromatization | |
| Kianfar | Investigation of the effect of crystallization temperature and time in synthesis of SAPO-34 catalyst for the production of light olefins | |
| Shang et al. | Seed-fused ZSM-5 nanosheet as a superior MTP catalyst: Synergy of micro/mesopore and inter/external acidity | |
| Wu et al. | Methylation of naphthalene on MTW-type zeolites. Influence of template origin and substitution of Al by Ga | |
| Jin et al. | Controllable synthesis of chainlike hierarchical ZSM-5 templated by sucrose and its catalytic performance | |
| Feng et al. | Direct synthesis of b-axis oriented H-form ZSM-5 zeolites with an enhanced performance in the methanol to propylene reaction | |
| Yang et al. | Space-confined synthesis of zeolite Beta microspheres via steam-assisted crystallization | |
| Deng et al. | Promoting xylene production in benzene methylation using hierarchically porous ZSM-5 derived from a modified dry-gel route | |
| Xu et al. | Methane non-oxidative aromatization on Mo/ZSM-5: Effect of adding triethoxyphenylsilanes into the synthesis system of ZSM-5 | |
| Qi et al. | High activity in catalytic cracking of large molecules over a novel micro-micro/mesoporous silicoaluminophosphate | |
| Wu et al. | Effect of ZSM-5 zeolite morphology on the catalytic performance of the alkylation of toluene with methanol | |
| Jin et al. | Synthesis of hierarchical ZSM-5 by cetyltrimethylammonium bromide assisted self-assembly of zeolite seeds and its catalytic performances | |
| Shi et al. | Hierarchically structured Pt/K-Beta zeolites for the catalytic conversion of n-heptane to aromatics | |
| Li et al. | Synthesis of SSZ-13 zeolite with zeolite L-added synthesis gel absent from additional aluminum source | |
| Liu et al. | Mother liquor induced preparation of SAPO-34 zeolite for MTO reaction | |
| Chen et al. | Synthesis of nano-ZSM-5 zeolite via a dry gel conversion crystallization process and its application in MTO reaction | |
| CN114471674A (en) | Carbon nano tube/ZSM-5 molecular sieve compound and synthesis method and application thereof | |
| Wei et al. | Co-conversion of methanol and n-hexane into aromatics using intergrown ZSM-5/ZSM-11 as a catalyst | |
| Li et al. | One-step synthesis of hierarchical ZSM-5 zeolites and their catalytic performance on the conversion of methanol to aromatics | |
| CN107952477B (en) | Application of hierarchical pore SAPO molecular sieve in methanol-to-olefin reaction | |
| CN107020145B (en) | Mesoporous IM-5 molecular sieve and preparation method thereof |
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 |