JP3250714B2 - Oxide-supported catalyst carrier, method for producing the same, and catalyst for purifying exhaust gas - Google Patents
Oxide-supported catalyst carrier, method for producing the same, and catalyst for purifying exhaust gasInfo
- Publication number
- JP3250714B2 JP3250714B2 JP35199695A JP35199695A JP3250714B2 JP 3250714 B2 JP3250714 B2 JP 3250714B2 JP 35199695 A JP35199695 A JP 35199695A JP 35199695 A JP35199695 A JP 35199695A JP 3250714 B2 JP3250714 B2 JP 3250714B2
- Authority
- JP
- Japan
- Prior art keywords
- oxide
- carrier
- substrate
- supported
- solution
- 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.)
- Expired - Fee Related
Links
- 239000003054 catalyst Substances 0.000 title claims description 94
- 238000004519 manufacturing process Methods 0.000 title claims description 24
- 239000010412 oxide-supported catalyst Substances 0.000 title claims description 15
- 239000000758 substrate Substances 0.000 claims description 83
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 59
- 239000002243 precursor Substances 0.000 claims description 55
- 238000000034 method Methods 0.000 claims description 52
- 239000000243 solution Substances 0.000 claims description 50
- 239000011148 porous material Substances 0.000 claims description 42
- 239000002131 composite material Substances 0.000 claims description 36
- 239000002245 particle Substances 0.000 claims description 29
- 239000002244 precipitate Substances 0.000 claims description 26
- 238000001556 precipitation Methods 0.000 claims description 23
- 239000002002 slurry Substances 0.000 claims description 22
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 19
- 229910052726 zirconium Inorganic materials 0.000 claims description 19
- 239000010948 rhodium Substances 0.000 claims description 17
- HSJPMRKMPBAUAU-UHFFFAOYSA-N cerium nitrate Inorganic materials [Ce+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O HSJPMRKMPBAUAU-UHFFFAOYSA-N 0.000 claims description 16
- 239000006104 solid solution Substances 0.000 claims description 16
- 229910000420 cerium oxide Inorganic materials 0.000 claims description 15
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 claims description 15
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 claims description 15
- 229910001928 zirconium oxide Inorganic materials 0.000 claims description 15
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 claims description 14
- 229910000510 noble metal Inorganic materials 0.000 claims description 14
- 229910052684 Cerium Inorganic materials 0.000 claims description 13
- 238000000975 co-precipitation Methods 0.000 claims description 13
- 230000008859 change Effects 0.000 claims description 12
- 229910052703 rhodium Inorganic materials 0.000 claims description 12
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims description 12
- 150000003839 salts Chemical class 0.000 claims description 12
- 229910052723 transition metal Inorganic materials 0.000 claims description 12
- 229910052782 aluminium Inorganic materials 0.000 claims description 11
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 11
- 150000003624 transition metals Chemical class 0.000 claims description 11
- 229910052783 alkali metal Inorganic materials 0.000 claims description 10
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims description 10
- 150000001342 alkaline earth metals Chemical class 0.000 claims description 10
- 229910052746 lanthanum Inorganic materials 0.000 claims description 10
- 230000008569 process Effects 0.000 claims description 10
- 239000002253 acid Substances 0.000 claims description 9
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 150000001340 alkali metals Chemical class 0.000 claims description 8
- 229910052788 barium Inorganic materials 0.000 claims description 8
- 238000010304 firing Methods 0.000 claims description 7
- 239000011259 mixed solution Substances 0.000 claims description 7
- 230000009257 reactivity Effects 0.000 claims description 7
- 238000002156 mixing Methods 0.000 claims description 6
- 230000003647 oxidation Effects 0.000 claims description 5
- 238000007254 oxidation reaction Methods 0.000 claims description 5
- 239000002585 base Substances 0.000 claims description 4
- OERNJTNJEZOPIA-UHFFFAOYSA-N zirconium nitrate Chemical compound [Zr+4].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O OERNJTNJEZOPIA-UHFFFAOYSA-N 0.000 claims description 4
- 230000001376 precipitating effect Effects 0.000 claims description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 79
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 description 55
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 description 55
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 21
- 239000007864 aqueous solution Substances 0.000 description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 15
- 230000000694 effects Effects 0.000 description 14
- 238000012360 testing method Methods 0.000 description 14
- 239000000843 powder Substances 0.000 description 13
- 230000000052 comparative effect Effects 0.000 description 11
- 239000003795 chemical substances by application Substances 0.000 description 10
- 229910052697 platinum Inorganic materials 0.000 description 10
- 239000000725 suspension Substances 0.000 description 10
- 229910002651 NO3 Inorganic materials 0.000 description 9
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 9
- 239000000969 carrier Substances 0.000 description 9
- 230000003472 neutralizing effect Effects 0.000 description 9
- 238000000746 purification Methods 0.000 description 9
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 8
- 238000002441 X-ray diffraction Methods 0.000 description 8
- 235000011114 ammonium hydroxide Nutrition 0.000 description 8
- 239000007789 gas Substances 0.000 description 8
- 229910052760 oxygen Inorganic materials 0.000 description 8
- 239000011163 secondary particle Substances 0.000 description 8
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 7
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 7
- 239000003426 co-catalyst Substances 0.000 description 7
- 229910017604 nitric acid Inorganic materials 0.000 description 7
- UJVRJBAUJYZFIX-UHFFFAOYSA-N nitric acid;oxozirconium Chemical compound [Zr]=O.O[N+]([O-])=O.O[N+]([O-])=O UJVRJBAUJYZFIX-UHFFFAOYSA-N 0.000 description 7
- 239000001301 oxygen Substances 0.000 description 7
- 239000000126 substance Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000003513 alkali Substances 0.000 description 6
- 230000007423 decrease Effects 0.000 description 6
- 239000012266 salt solution Substances 0.000 description 6
- 238000003860 storage Methods 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 5
- 230000006870 function Effects 0.000 description 5
- 238000005470 impregnation Methods 0.000 description 5
- 239000003094 microcapsule Substances 0.000 description 5
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 4
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 4
- 230000009471 action Effects 0.000 description 4
- -1 alkali metal salt Chemical class 0.000 description 4
- 229910052791 calcium Inorganic materials 0.000 description 4
- 239000011575 calcium Substances 0.000 description 4
- 229910002091 carbon monoxide Inorganic materials 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 239000006185 dispersion Substances 0.000 description 4
- 229930195733 hydrocarbon Natural products 0.000 description 4
- 150000002430 hydrocarbons Chemical class 0.000 description 4
- 229910052749 magnesium Inorganic materials 0.000 description 4
- 239000011777 magnesium Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229910052700 potassium Inorganic materials 0.000 description 4
- 239000000377 silicon dioxide Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000004448 titration Methods 0.000 description 4
- IVORCBKUUYGUOL-UHFFFAOYSA-N 1-ethynyl-2,4-dimethoxybenzene Chemical compound COC1=CC=C(C#C)C(OC)=C1 IVORCBKUUYGUOL-UHFFFAOYSA-N 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 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 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 3
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 3
- 229910052790 beryllium Inorganic materials 0.000 description 3
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 3
- 150000004820 halides Chemical class 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 3
- 150000004679 hydroxides Chemical class 0.000 description 3
- 229910052744 lithium Inorganic materials 0.000 description 3
- 150000007522 mineralic acids Chemical class 0.000 description 3
- 150000007524 organic acids Chemical class 0.000 description 3
- 238000010979 pH adjustment Methods 0.000 description 3
- 230000000737 periodic effect Effects 0.000 description 3
- 239000011591 potassium Substances 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 230000000087 stabilizing effect Effects 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 2
- DDPNPTNFVDEJOH-UHFFFAOYSA-N [O-2].[Zr+4].[O-2].[Ce+3] Chemical compound [O-2].[Zr+4].[O-2].[Ce+3] DDPNPTNFVDEJOH-UHFFFAOYSA-N 0.000 description 2
- 150000001242 acetic acid derivatives Chemical class 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 238000001354 calcination Methods 0.000 description 2
- ZCCIPPOKBCJFDN-UHFFFAOYSA-N calcium nitrate Chemical compound [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ZCCIPPOKBCJFDN-UHFFFAOYSA-N 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- UNJPQTDTZAKTFK-UHFFFAOYSA-K cerium(iii) hydroxide Chemical compound [OH-].[OH-].[OH-].[Ce+3] UNJPQTDTZAKTFK-UHFFFAOYSA-K 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 2
- 239000002612 dispersion medium Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 2
- 238000011068 loading method Methods 0.000 description 2
- 150000002823 nitrates Chemical class 0.000 description 2
- 235000005985 organic acids Nutrition 0.000 description 2
- 239000012466 permeate Substances 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- NWAHZABTSDUXMJ-UHFFFAOYSA-N platinum(2+);dinitrate Chemical compound [Pt+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O NWAHZABTSDUXMJ-UHFFFAOYSA-N 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 229910052761 rare earth metal Inorganic materials 0.000 description 2
- 150000002910 rare earth metals Chemical class 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 238000003746 solid phase reaction Methods 0.000 description 2
- 238000010671 solid-state reaction Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000000954 titration curve Methods 0.000 description 2
- 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 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- ODUCDPQEXGNKDN-UHFFFAOYSA-N Nitrogen oxide(NO) Natural products O=N ODUCDPQEXGNKDN-UHFFFAOYSA-N 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910001593 boehmite Inorganic materials 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- 235000012255 calcium oxide Nutrition 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 description 1
- QCCDYNYSHILRDG-UHFFFAOYSA-K cerium(3+);trifluoride Chemical compound [F-].[F-].[F-].[Ce+3] QCCDYNYSHILRDG-UHFFFAOYSA-K 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000003995 emulsifying agent Substances 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- FAHBNUUHRFUEAI-UHFFFAOYSA-M hydroxidooxidoaluminium Chemical compound O[Al]=O FAHBNUUHRFUEAI-UHFFFAOYSA-M 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- SJLOMQIUPFZJAN-UHFFFAOYSA-N oxorhodium Chemical compound [Rh]=O SJLOMQIUPFZJAN-UHFFFAOYSA-N 0.000 description 1
- 239000011238 particulate composite Substances 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 150000003057 platinum Chemical class 0.000 description 1
- 239000011164 primary particle Substances 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 229910003450 rhodium oxide Inorganic materials 0.000 description 1
- VXNYVYJABGOSBX-UHFFFAOYSA-N rhodium(3+);trinitrate Chemical compound [Rh+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VXNYVYJABGOSBX-UHFFFAOYSA-N 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 239000012756 surface treatment agent Substances 0.000 description 1
- 150000003568 thioethers Chemical class 0.000 description 1
- 229910000314 transition metal oxide Inorganic materials 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、酸化物を担持した
触媒用担体の製造方法に関する。特に、好ましくは排ガ
ス浄化用触媒の複合酸化物担持担体の製造方法として用
いられる。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a catalyst support carrying an oxide. In particular, it is preferably used as a method for producing a composite oxide-supported carrier for an exhaust gas purifying catalyst.
【０００２】[0002]
【従来の技術】触媒用担体に担持される酸化物や複合酸
化物は一般的に触媒機能の向上や、触媒の劣化抑制など
の助触媒的な役割を担っており、触媒を有効に活用する
時になくてはならないものである。この様な働きをする
複合酸化物の代表的なものにはセリウムの酸化物（セリ
ア）やジルコニウムの酸化物（ジルコニア）があり、複
合酸化物としてはこれらの複合体がよく用いられる。2. Description of the Related Art In general, oxides and composite oxides carried on a catalyst carrier have a role of a co-catalyst, such as improving a catalyst function and suppressing deterioration of the catalyst. It is sometimes necessary. Representative examples of the composite oxide having such a function include cerium oxide (ceria) and zirconium oxide (zirconia), and these composites are often used as the composite oxide.
【０００３】セリアは酸素吸蔵能（ＯＳＣ）があり、酸
素を吸収・放出し、触媒使用雰囲気の調整をする働きが
あるが、高温にさらされると劣化しその能力が低下す
る。しかし、このセリアの高温劣化はジルコニアをセリ
アの回りに配置することによって抑制される。ジルコニ
アはセリア以外の助触媒物質や触媒物質の高温安定化に
対しても有効である。[0003] Ceria has an oxygen storage capacity (OSC), and functions to absorb and release oxygen and to adjust the atmosphere in which the catalyst is used. However, when exposed to high temperatures, it deteriorates and its ability decreases. However, this high-temperature deterioration of ceria is suppressed by arranging zirconia around ceria. Zirconia is also effective for stabilizing a co-catalyst material other than ceria and a catalyst material at a high temperature.
【０００４】酸化物を担体に担持する方法として、従
来、含浸法、粉末添加法、共沈法などが行われていた。
含浸法は焼成などによって酸化物となる物質（酸化物前
駆体）を生成する物質（酸化物前駆体生成物質）を水な
どの溶媒に溶解し、その溶液を担体に含浸させ含浸させ
た酸化物前駆体を酸化物に変化させる方法であるが（特
開昭63-116741 、特開昭63-116742 、特開平5-27737
5）、この方法によるとできた担体の細孔が閉塞されそ
の表面積が低下するという問題があった。[0004] As a method of supporting an oxide on a carrier, an impregnation method, a powder addition method, a coprecipitation method, and the like have been conventionally performed.
The impregnation method involves dissolving a substance (oxide precursor-forming substance) that produces a substance (oxide precursor) that becomes an oxide upon firing or the like in a solvent such as water, and impregnating the carrier with the solution to impregnate the oxide. It is a method of changing a precursor to an oxide (Japanese Patent Application Laid-Open Nos. 63-116741, 63-116742, 5-27737).
5) According to this method, there is a problem that pores of the carrier formed are closed and the surface area thereof is reduced.
【０００５】粉末添加法は、沈殿等により酸化物の前駆
体を得、これを焼成等により酸化し、できた酸化物を、
粉砕・混合した後、スラリー状にするなどして担体に担
持するものであるが、担持される粉末の粒子径が大きく
なりやすく、このような酸化物担持担体に貴金属等の触
媒を担持した時には触媒が担体にうまく分散せず助触媒
となる酸化物との相互作用が不十分で触媒能が十分に発
揮されない（特開昭60-110334 、特開平5-270823、特開
平4-55315)。[0005] In the powder addition method, an oxide precursor is obtained by precipitation or the like, and this is oxidized by firing or the like.
After being crushed and mixed, it is to be supported on a carrier by making it into a slurry, etc., but the particle diameter of the supported powder tends to be large, and when a catalyst such as a noble metal is supported on such an oxide-supported carrier. The catalyst does not disperse well in the carrier and the interaction with the oxide serving as a cocatalyst is insufficient, so that the catalytic ability is not sufficiently exhibited (Japanese Patent Application Laid-Open Nos. 60-110334, 5-70823 and 4-55315).
【０００６】共沈法は、溶解させた複数の酸化物前駆体
発生物質から複数の酸化物前駆体を同時に沈殿させ複数
の酸化物前駆体が混合した析出物を作り、これを直接担
体に塗布し焼成などにより担体上で複合酸化物化する、
あるいはアルミナなどの基体を共沈発生溶液に共存させ
酸化物前駆体を基体上に析出させた後、析出させた共沈
を複合酸化物に変換する（特開平5 -286722 、 特開平
6-063403、 特開平6-114264、特開平5 -270823 ) 、さ
らには析出物から複合酸化物を作製し、それを粉末添加
法と同様に担体に担持することによって複合酸化物担持
担体を作製する方法などがある。In the coprecipitation method, a plurality of oxide precursors are simultaneously precipitated from a plurality of dissolved oxide precursor generating materials to form a precipitate in which a plurality of oxide precursors are mixed, and this is directly applied to a carrier. To form a composite oxide on the carrier by baking, etc.
Alternatively, after an oxide precursor is deposited on a substrate by allowing a substrate such as alumina to coexist in a coprecipitation generating solution, the deposited coprecipitate is converted into a composite oxide (Japanese Patent Application Laid-Open Nos. 5-286722 and 5-286722).
6-063403, JP-A-6-114264, JP-A-5-270823), and a composite oxide-supported carrier is produced by preparing a composite oxide from the precipitate and supporting it on the carrier in the same manner as in the powder addition method. There are ways to do that.
【０００７】しかし、この方法にも含浸法や粉末添加法
と同様の問題点があった。また、固溶体化や異種酸化物
同士の分散状態が十分ではなく、完全に複合化したとは
いい難い状態であった。ここで、固溶体とは複合体の中
でも特に両酸化物の混合状態が原子レベルのものをい
う。However, this method has the same problems as the impregnation method and the powder addition method. In addition, the solid solution and the dispersion state of the different oxides were not sufficient, and it was difficult to say that they were completely complex. Here, the solid solution refers to a complex in which the mixed state of both oxides is at the atomic level.
【０００８】単一酸化物を担持する従来の方法、さらに
は複合酸化物を担持させる従来の方法、いづれの方法を
とっても、セリアとジルコニアの両者を任意の割合で混
合し複合化させることは困難であった。なぜなら、従来
の方法により両酸化物の粉末を混合して複合体化させた
場合には、両粉末の微細化・分散化が不十分であり、ど
ちらかの成分に偏った複合体しか得られなかった。ま
た、共沈法で両酸化物の前駆体の混合体を析出させた場
合にも往々にして遍析が生じやすく、やはり、どちらの
成分に偏った複合体しか得られなかった。[0008] It is difficult to mix both ceria and zirconia at an arbitrary ratio to form a composite by any of the conventional method of supporting a single oxide and the conventional method of supporting a composite oxide. Met. Because, when the powders of both oxides are mixed by a conventional method to form a composite, the fineness and dispersion of both powders are insufficient, and only a composite biased toward one of the components is obtained. Did not. Also, when a mixture of precursors of both oxides was precipitated by the coprecipitation method, eutectic tended to occur in many cases, and only a composite having a bias in either component was obtained.
【０００９】[0009]
【発明が解決しようとする課題】本発明は、上記従来技
術の問題点を解消し、担持酸化物粒子の微粒子化、高分
散化が図ることができる酸化物担持触媒担体および複合
酸化物担持触媒担体の製造方法を提供しようとするもの
である。さらに、900 ℃以上の高温熱履歴を受けた後に
おいても十分な助触媒作用を発揮する酸化物担持触媒担
体および複合酸化物担持触媒担体の製造方法を提供しよ
うとするものである。SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and enables an oxide-carrying catalyst carrier and a composite oxide-carrying catalyst to achieve finer particles and higher dispersion of the supported oxide particles. It is intended to provide a method for producing a carrier. It is another object of the present invention to provide a method for producing an oxide-carrying catalyst carrier and a composite oxide-carrying catalyst carrier which exhibit a sufficient co-catalyst function even after being subjected to a high-temperature heat history of 900 ° C. or more.
【００１０】[0010]
【課題を解決するための手段】（第１発明） 本発明の酸化物担持触媒担体の製造方法は、沈殿により
遷移金属、アルミニウム、アルカリ土類金属あるいはア
ルカリ金属から選ばれたセリウムを含む少なくとも１つ
の元素の酸化物前駆体を生成する溶液を調製する第１工
程と、細孔を有する基体と該第１工程の溶液との反応を
防止するために該基体の該溶液に対する反応性を低下さ
せる処理を該基体に施す第２工程と、Means for Solving the Problems (First invention) The method for producing an oxide-supported catalyst carrier of the present invention is characterized in that at least one of cerium containing a cerium selected from transition metals, aluminum, alkaline earth metals or alkali metals is precipitated. A first step of preparing a solution that produces an oxide precursor of the two elements; and reducing the reactivity of the substrate to the solution to prevent reaction between the substrate having pores and the solution of the first step. A second step of performing a treatment on the substrate;
【００１１】該第１工程により調製された溶液と該第２
工程により反応性を低下させた基体とを混合してスラリ
ーとする第３工程と、該第３工程における該溶液と該基
体の混合後10分以内で混合溶液に該酸化物前駆体の沈殿
もしくは共沈を発生させる沈殿発生処理を施し、該基体
表面近傍および／または該基体の細孔内で該酸化物前駆
体を沈殿もしくは共沈させる第４工程と、該沈殿もしく
は共沈した該酸化物前駆体を酸化物に変換させる第５工
程とからなり、900 ℃の空気中において５時間以上加熱
した時の酸化セリウム粒子径が10nm以下である特性をも
つ酸化物担持触媒担体の製造方法。The solution prepared in the first step and the second
Slurry by mixing with substrate with reduced reactivity by process
Third step and, third solution and said substrate mixture within 10 minutes after mixing subjected to precipitation or sedimentation generation process for generating a co-precipitation of oxide precursors of the process, said substrate surface to over the oxide precursor in the vicinity and / or the pores of the base body
A fourth step of precipitating or coprecipitating body, Ri Do and a fifth step of converting the oxide precursors precipitate or coprecipitate to oxide, 5 hours or more at 900 ° C. in air heated
The cerium oxide particle size when
A method for producing an oxide-carrying catalyst carrier.
【００１２】本発明に用いる基体には酸化物前駆体を溶
解した溶液に不溶で、触媒担体としての使用が可能な程
度の細孔径を有するものであれば何でも用いることがで
きる。たとえば、アルミナ、活性アルミナ、Laで安定化
したアルミナもしくは活性アルミナ、シリカ、シリカア
ルミナ、ゼオライト、モルデナイトなどを用いることが
できる。また、ＮＯｘ浄化用、三元触媒用の担体も用い
ることができる。酸化物前駆体は遷移金属、アルミニウ
ム、アルカリ土類金属あるいはアルカリ金属等の水酸化
物、硫化物、ハロゲン化物、およびその他の有機酸、無
機酸との塩、あるいはアンモニア、水酸基等との錯体な
どであり、酸化処理や焼成を行うことによって金属の酸
化物に変換できるものを意味する。As the substrate used in the present invention, any substrate can be used as long as it is insoluble in the solution in which the oxide precursor is dissolved and has a pore size that can be used as a catalyst carrier. For example, alumina, activated alumina, alumina stabilized with La or activated alumina, silica, silica alumina, zeolite, mordenite and the like can be used. Further, a carrier for NOx purification and a three-way catalyst can also be used. Oxide precursors include hydroxides, sulfides, halides, and other organic and inorganic acids of transition metals, aluminum, alkaline earth metals, and alkali metals, and complexes with ammonia and hydroxyl groups. Which means that it can be converted to a metal oxide by performing an oxidation treatment or firing.
【００１３】遷移金属には希土類金属やジルコニウムを
含む。即ち、周期律表の第４、第５、第６周期の１Ｂ、
２Ｂ、３Ａ、４Ａ、５Ａ、６Ａ、７Ａ、８族の金属を意
味する。また、アルカリ金属、アルカリ土類金属とは、
リチウム、ナトリウム、カリウム、ベリリウム、マグネ
シウム、カルシウム等の周期律表の第２〜第７周期の１
Ａ、２Ａ族の元素を意味する。また、この触媒の利用目
的としては、一般的排気浄化触媒として用いることがで
きる。たとえば、三元触媒、ＮＯｘ触媒あるいは酸化触
媒などの担体、あるいは担体の一部、および助触媒の担
持方法に関するものである。The transition metals include rare earth metals and zirconium. That is, 1B of the fourth, fifth, and sixth periods of the periodic table,
Group 2B, 3A, 4A, 5A, 6A, 7A, Group 8 metals. Also, alkali metals and alkaline earth metals are
One of the 2nd to 7th periods of the periodic table for lithium, sodium, potassium, beryllium, magnesium, calcium, etc.
It means an element of group A or 2A. The catalyst can be used as a general exhaust gas purification catalyst. For example, the present invention relates to a carrier such as a three-way catalyst, a NOx catalyst or an oxidation catalyst, or a part of the carrier, and a method for supporting a promoter.
【００１４】第２工程の基体の処理工程は細孔を有する
基体と酸化物前駆体発生溶液との反応を防止するために
該基体の該溶液に対する反応性を低下させるため基体に
反応抑制処理を行うことである。本工程としては酸化物
前駆体発生溶液と基体との反応が抑制される方法ならど
んな方法でも採用することができる。その工程としてた
とえば、基体のpH調整、表面処理剤による親水性処理、
疎水性処理あるいは表面修飾処理などを用いることがで
きる。In the second step of treating the substrate, a reaction suppression treatment is performed on the substrate to reduce the reactivity of the substrate with the oxide precursor generating solution in order to prevent the reaction between the substrate having pores and the solution. Is to do. As this step, any method can be adopted as long as the reaction between the oxide precursor generating solution and the substrate is suppressed. As the process, for example, pH adjustment of the substrate, hydrophilic treatment with a surface treatment agent,
A hydrophobic treatment or a surface modification treatment can be used.
【００１５】また、第３工程の沈殿発生処理とは物質の
化学的性質、物理的性質を利用して沈殿を発生させる方
法をいい、物理的衝撃、pHの変化、凝集剤、あるいは化
学反応等により単一の沈殿を発生させたり、複数の沈殿
を同時に発生させる処理をいう。また、第５工程の酸化
物への変換工程としては、焼成処理、酸化処理などが用
いられる。[0015] The precipitation generation treatment in the third step refers to a method of generating a precipitate by utilizing the chemical and physical properties of a substance, such as physical impact, pH change, coagulant, or chemical reaction. Means that a single precipitate is generated or a plurality of precipitates are generated at the same time. In addition, a baking treatment, an oxidation treatment, or the like is used as the fifth step of converting into an oxide.
【００１６】（第２発明）前記請求項１記載の酸化物担
持触媒担体の製造方法において第２工程の処理工程をpH
調整工程とした酸化物担持触媒担体の製造方法。pH調整
とは酸やアルカリを加えて基体のpHを任意に設定するこ
とであり、基体に酸やアルカリを含浸させるなどの方法
がとられる。(Second invention) In the method for producing an oxide-carrying catalyst carrier according to the first aspect, the treatment step of the second step is carried out at pH
A method for producing an oxide-supported catalyst carrier as an adjusting step. The pH adjustment is to arbitrarily set the pH of the substrate by adding an acid or an alkali, and a method of impregnating the substrate with an acid or an alkali is used.
【００１７】（第３発明） 本発明の酸化物担持触媒担体の製造方法は、遷移金属、
アルミニウム、アルカリ土類金属あるいはアルカリ金属
から選ばれ少なくともセリウムを含む２種以上の元素の
塩を溶解した溶液を調製する第１工程と、細孔を有する
基体のpHを調整する第２工程と、該第１工程の溶液と該
第２工程後の基体とを混合してスラリーとする第３工程
と、該第３工程後の混合溶液のpHを沈殿発生剤を用いて
数分以内で急速に該２種以上の元素の酸化物前駆体の共
沈が始まるpH域に変化させ、該２種以上の元素の酸化物
前駆体の共沈を発生させる第４工程と、該共沈した酸化
物前駆体を複合酸化物に変換させる第５工程とからな
り、900℃の空気中において５時間以上加熱した時の酸
化セリウム粒子径が10nm以下である特性をもつ。(Third Invention) A method for producing an oxide-supported catalyst carrier of the present invention comprises a transition metal,
Aluminum, a first step of preparing a solution in which a salt of at least two elements selected from alkaline earth metals or alkali metals and containing at least cerium is dissolved, and a second step of adjusting the pH of the substrate having pores, A third step of mixing the solution of the first step and the substrate after the second step to form a slurry, and rapidly adjusting the pH of the mixed solution after the third step to within several minutes using a precipitation generator. A fourth step of changing the pH to a pH range at which the co-precipitation of the oxide precursor of the two or more elements starts, and causing the co-precipitation of the oxide precursor of the two or more elements; A fifth step of converting the precursor to a composite oxide.
Acid when heated for 5 hours or more in air at 900 ° C
It has the characteristic that the cerium fluoride particle size is 10 nm or less .
【００１８】遷移金属、アルカリ土類金属あるいはアル
カリ金属の塩とは周期律表の第２、第３、第４、第５、
第６周期の１Ａ、２Ａ、１Ｂ、２Ｂ、３Ａ、４Ａ、５
Ａ、６Ａ、７Ａ、８族、特に、ランタン、ジルコニウ
ム、セリウム、およびリチウム、ナトリウム、カリウ
ム、ベリリウム、マグネシウム、カルシウムなどのハロ
ゲン化物および有機酸、無機酸などとの水溶性の塩を指
す。好適には硝酸塩、酢酸塩などである。本発明に用い
る基体には前記塩を溶解した溶液に不溶で、触媒担体と
しての使用が可能な程度の細孔径を有するものであれば
何でも用いることができる。好適には酸化アルミニウム
（アルミナ、活性アルミナ）、シリカ、ゼオライト等が
用いられる。基体のpH調整とは酸やアルカリを加えて基
体のpHを任意に設定することであり、基体に酸やアルカ
リを含浸させるなどの方法がとられる。沈殿発生剤とし
ては、アンモア、炭酸ナトリウム、水酸化ナトリウム等
のアルカリ、炭酸、酢酸、硝酸等の酸が用いられる。The transition metal, alkaline earth metal or alkali metal salt is defined as the second, third, fourth, fifth, or
6A 1A, 2A, 1B, 2B, 3A, 4A, 5
Groups A, 6A, 7A, 8 refer to lanthanum, zirconium, cerium, and halides such as lithium, sodium, potassium, beryllium, magnesium, calcium, and water-soluble salts with organic acids, inorganic acids, and the like. Preferred are nitrates and acetates. As the substrate used in the present invention, any one can be used as long as it is insoluble in the solution in which the salt is dissolved and has a pore diameter that can be used as a catalyst carrier. Preferably, aluminum oxide (alumina, activated alumina), silica, zeolite or the like is used. Adjusting the pH of the substrate means arbitrarily setting the pH of the substrate by adding an acid or alkali, and a method of impregnating the substrate with an acid or alkali is used. As the precipitation generator, alkalis such as ammore, sodium carbonate and sodium hydroxide, and acids such as carbonic acid, acetic acid and nitric acid are used.
【００１９】酸化物複合体とは複数の酸化物がミクロあ
るいはマクロに分散して存在する混合体、さらにこれら
が溶解し合って一体化したもの、さらには複数の酸化物
が原子レベルで混合し合ったいわゆる固溶体などをい
う。また、共沈発生処理とはいわゆるpHの変化をすべて
の酸化物前駆体が沈殿する領域までアルカリ、酸によっ
て変化させ複数の酸化物前駆体を共に発生させる処理を
いう。また、酸化物への変換工程としては、焼成処理、
酸化処理などが用いられる。An oxide composite is a mixture in which a plurality of oxides are dispersed in a micro or macro form, a mixture in which these are dissolved and integrated, and a plurality of oxides are mixed at an atomic level. It refers to a so-called combined solid solution. In addition, the coprecipitation generation treatment refers to a treatment in which a change in pH is changed by an alkali or an acid to a region where all oxide precursors are precipitated to generate a plurality of oxide precursors together. In addition, as a conversion step to the oxide, baking treatment,
An oxidation treatment or the like is used.
【００２０】（第４発明）第３発明の工程に加えて細孔
を有する基体と複数の遷移金属の塩を溶解した溶液との
反応を防止するために、pHを調整したスラリー（懸濁
液）状の基体を作製する基体処理工程を行う。pHの調整
は基体に酸やアルカリを加えることによって行う。ま
た、本発明のスラリーは基体粒子が溶液に単純に分散し
たものでよく、また、分散剤、乳化剤等を加えて分散性
を向上させたものでもよい。(Fourth Invention) In addition to the process of the third invention, a slurry (suspension) in which the pH is adjusted to prevent a reaction between a substrate having pores and a solution in which a plurality of transition metal salts are dissolved is prevented. A substrate processing step of producing a substrate in the shape of ()) is performed. The pH is adjusted by adding an acid or an alkali to the substrate. The slurry of the present invention may be one in which the base particles are simply dispersed in a solution, or one in which a dispersant, an emulsifier, or the like is added to improve the dispersibility.
【００２１】（第５発明）第４発明の２種以上の元素と
してセリウムおよびジルコニウムの硝酸塩を、基体とし
てアルミナを用い、酸化セリウムと酸化ジルコニウムの
固溶体を担持した担体を得る酸化物担持触媒担体の製造
方法。 （第６発明）第５発明のアルミナとしてLaあるいはBaで
安定化したアルミナを用いる酸化物担持触媒担体の製造
方法。通常触媒担体として用いられるLaもしくはBa安定
化アルミナであればどんな形状、細孔径、細孔分布のも
のでも使用することができる。(Fifth Invention) An oxide-supported catalyst carrier which obtains a carrier carrying a solid solution of cerium oxide and zirconium oxide using cerium and zirconium nitrate as two or more elements of the fourth invention and alumina as a substrate. Production method. (Sixth invention) A method for producing an oxide-carrying catalyst carrier using alumina stabilized with La or Ba as the alumina of the fifth invention. Any La, Ba-stabilized alumina generally used as a catalyst carrier can be used having any shape, pore diameter and pore distribution.
【００２２】（第７発明）第３発明、第４発明、第５発
明、第６発明のpH変化工程においてpHをpH1 からpH7 へ
数分以内に急速に変化させる酸化物担持触媒担体の製造
方法。好ましくは１分以内に上記範囲のpH変化を起こさ
せることが望ましい。(Seventh invention) A method for producing an oxide-carrying catalyst carrier in which the pH is rapidly changed from pH1 to pH7 within several minutes in the pH change step of the third invention, the fourth invention, the fifth invention, and the sixth invention. . It is desirable to cause the pH change in the above range preferably within one minute.
【００２３】（第８発明〜第１３発明）第５発明の方法
によって製造された酸化セリウムが酸化ジルコニウムと
酸化セリウムの合計に対する金属の原子比で10% 以上、
80% 以下含有された酸化ジルコニウム−酸化セリウム固
溶体担持La安定化アルミナ担体、好適には酸化ジルコニ
ウムが酸化ジルコニウムと酸化セリウムの合計に対しモ
ル比で20% 以上、60% 以下の担体、さらに好適には酸化
ジルコニウムが酸化ジルコニウムと酸化セリウムの合計
に対しモル比で40% 以上、55% 以下の担体、さらにはこ
れら担体に貴金属触媒を担持した触媒。(Eighth to thirteenth inventions) The cerium oxide produced by the method of the fifth invention has an atomic ratio of metal of 10% or more to the total of zirconium oxide and cerium oxide,
A zirconium oxide-cerium oxide solid solution-supported La-stabilized alumina carrier containing not more than 80%, preferably a carrier in which zirconium oxide has a molar ratio of 20% or more and 60% or less to the total of zirconium oxide and cerium oxide, more preferably Is a carrier in which zirconium oxide has a molar ratio of 40% or more and 55% or less with respect to the total of zirconium oxide and cerium oxide, and a catalyst in which a noble metal catalyst is supported on these carriers.
【００２４】酸化セリウムの酸化ジルコニウムと酸化セ
リウムとからなる複合体に対する含有量がモル比で40%
以下、時には20% 以下、特に10% 以下の場合にはセリア
の酸素吸蔵能力が十分ではない。酸化セリウムの含有量
が55% 以上、時には60% 以上、特に90% 以上ではジルコ
ニアによる耐熱性向上効果が十分に発揮されない。第５
発明の方法によって製造された900 ℃の空気中において
５時間以上加熱した時の表面積が80ｍ2 /g以上の酸化ジ
ルコニウム−酸化セリウム固溶体担持La安定化アルミナ
担体、さらには900 ℃の空気中において５時間以上加熱
した時のセリア粒子径が10nm以下のもの。The content of cerium oxide with respect to the complex comprising zirconium oxide and cerium oxide is 40% by mole.
Below, sometimes below 20%, especially below 10%, the oxygen storage capacity of ceria is not sufficient. When the content of cerium oxide is 55% or more, sometimes 60% or more, particularly 90% or more, the effect of zirconia on improving heat resistance is not sufficiently exhibited. Fifth
A La-stabilized alumina carrier supporting a zirconium oxide-cerium oxide solid solution having a surface area of not less than 80 m 2 / g when heated in air at 900 ° C. for 5 hours or more, produced in the air at 900 ° C. Ceria particle diameter of 10 nm or less when heated for more than an hour.
【００２５】（第１４発明）第１発明もしくは第２発明
の方法において、前記第１工程の選択元素として少なく
ともジルコニウムを用いることによって製造された、酸
化ジルコニウム中のジルコニウムの担持量が前記基体に
対する金属の原子比で４％以上である酸化ジルコニウム
担持担体に、さらにロジウムを担持した排ガス浄化用触
媒。さらに、酸化ジルコニウムの担持量として、該基体
に対する金属の原子比で４％以上９５％以下が好適であ
る。(14th invention) In the method of the 1st invention or the 2nd invention, the amount of zirconium carried in the zirconium oxide produced by using at least zirconium as the selective element in the first step is a metal to the substrate. An exhaust gas purifying catalyst comprising rhodium further supported on a zirconium oxide-supported carrier having an atomic ratio of 4% or more. Further, the loading amount of zirconium oxide is preferably 4% or more and 95% or less in atomic ratio of metal to the substrate.
【００２６】[0026]
（第１発明）本発明の複合酸化物担持触媒担体の製造方
法では、第１工程で調製した、酸化物前駆体発生溶液を
第３工程において細孔を有する基体と混合させる。これ
により該溶液は基体表面近傍（基体の２次粒子表面近
傍）もしくは細孔中の極限られた領域に浸み渡り閉じ込
められた状態となる。これは前記表面近傍もしくは細孔
をマイクロカプセルとみなしその中に溶液が閉じ込めら
れた状態とも考えられる。このような状態は基体の吸着
力や吸収力によって作りだされると考えられる。(First Invention) In the method for producing a composite oxide-supported catalyst carrier of the present invention, the oxide precursor generating solution prepared in the first step is mixed with a substrate having pores in a third step. As a result, the solution is in a state of being entrapped and confined in the vicinity of the substrate surface (near the surface of the secondary particles of the substrate) or in a very limited region in the pores. This can be considered as a state in which the vicinity of the surface or the pores are regarded as microcapsules and the solution is confined therein. It is considered that such a state is created by the attraction or absorption of the substrate.
【００２７】その後、第３工程において限られた領域に
閉じ込められた酸化物前駆体を発生する溶液に沈殿発生
処理を施す。この過程で加えられる沈殿発生を誘起する
刺激は細孔を有する基体の細孔内や表面近傍の極小さな
限られた領域では大きく増幅されるので、沈殿特性の異
なる複数の酸化物前駆体でも極小さな限られた領域にお
いて高度に分散した微細な酸化物前駆体の沈殿を発生す
る。Thereafter, in the third step, a solution for generating an oxide precursor confined in a limited region is subjected to a precipitation generation treatment. The stimulus that induces the generation of precipitates added in this process is greatly amplified in the pores of the substrate having the pores or in a very small limited area near the surface, so that even a plurality of oxide precursors having different precipitation characteristics can be extremely amplified. Generates a precipitate of highly dispersed fine oxide precursors in small confined areas.
【００２８】基体が酸化物前駆体発生溶液と反応して酸
化物前駆体の沈殿が生じてしまうと沈殿物の粒成長が起
こり、その後変換された酸化物の助触媒としての働きが
低下してしまう。酸化物前駆体発生溶液として混合溶液
中を用いた場合では、もし溶液中の一部の酸化物前駆体
の沈殿が生じてしまうと、次の過程で酸化物前駆体の共
沈を発生させても沈殿物は遍析が生じたものと同じ結果
となり、複数の酸化物が高度に分散した複合酸化物を作
製できない。このため、本発明では第２工程を行ない酸
化物前駆体発生溶液に対し、沈殿を自然に誘発するよう
な基体表面の物理的あるいは化学的活性を低下させる。When the substrate reacts with the oxide precursor generating solution to cause precipitation of the oxide precursor, grain growth of the precipitate occurs, and thereafter, the function of the converted oxide as a cocatalyst decreases. I will. In the case where a mixed solution is used as an oxide precursor generation solution, if precipitation of some oxide precursors in the solution occurs, coprecipitation of the oxide precursor is generated in the next process. The sediment has the same result as that of the sedimentation, and a composite oxide in which a plurality of oxides are highly dispersed cannot be produced. Therefore, in the present invention, the second step is performed to reduce the physical or chemical activity of the substrate surface that naturally induces precipitation in the oxide precursor generation solution.
【００２９】本発明の方法によれば、細孔を有する基体
の表面あるいは細孔内に酸化物が高度に分散した触媒担
持用担体を作製することができる。本発明の方法によ
り、細孔を有する基体に酸化物を担持した時には酸化物
担持粒子の径が十分に小さく細孔の閉塞を生じない。従
って、得られた触媒担持用担体の表面積の低下が少な
く、担持した酸化物の助触媒としての能力が十分に発揮
され、さらに触媒を担持した時には触媒の作用が最大限
に発揮される。According to the method of the present invention, it is possible to prepare a catalyst-carrying carrier in which an oxide is highly dispersed on the surface of a substrate having pores or in pores. According to the method of the present invention, when an oxide is supported on a substrate having pores, the diameter of the oxide-carrying particles is sufficiently small so that the pores are not blocked. Therefore, the surface area of the obtained catalyst-carrying carrier is hardly reduced, the ability of the supported oxide as a co-catalyst is sufficiently exhibited, and when the catalyst is supported, the action of the catalyst is maximized.
【００３０】（第２発明）第１発明の第２工程において
基体のpHを酸化物前駆体発生溶液と基体との反応で酸化
物前駆体が沈殿しない領域へシフトさせることによっ
て、基体は酸化物前駆体発生溶液を安定にそのマイクロ
カプセル内に保持することができる。(Second Invention) In the second step of the first invention, by shifting the pH of the substrate to a region where the oxide precursor is not precipitated by the reaction between the oxide precursor generating solution and the substrate, the substrate is made of an oxide. The precursor generation solution can be stably held in the microcapsules.
【００３１】本工程を加えることによって酸化物前駆体
を含んだ溶液が基体と接触しても酸化物前駆体の沈殿物
が析出することはなく、沈殿物の粒子が大きく成長する
ことはない。従って、沈殿を酸化物に変換して細孔を有
する基体に酸化物を担持した時には酸化物担持粒子の径
が十分に小さく細孔の閉塞を生じない。従って、得られ
た触媒担持用担体の表面積の低下が少なく、担持した酸
化物の助触媒としての能力が十分に発揮され、さらに触
媒を担持した時には触媒の作用が最大限に発揮される。By adding this step, even if the solution containing the oxide precursor comes into contact with the substrate, the precipitate of the oxide precursor does not precipitate, and the particles of the precipitate do not grow large. Therefore, when the precipitate is converted into an oxide and the oxide is supported on a substrate having pores, the diameter of the oxide-carrying particles is sufficiently small and the pores are not blocked. Therefore, the surface area of the obtained catalyst-carrying carrier is hardly reduced, the ability of the supported oxide as a co-catalyst is sufficiently exhibited, and when the catalyst is supported, the action of the catalyst is maximized.
【００３２】（第３発明）本発明の複合酸化物担持触媒
担体の製造方法では、第１工程で調整した遷移金属、ア
ルミニウム、アルカリ土類金属あるいはアルカリ金属の
塩を溶解した溶液を第３工程において細孔を有する基体
と混合させる。前記塩とは周期律表の第２、第３、第
４、第５、第６周期の１Ａ、２Ａ、１Ｂ、２Ｂ、３Ａ、
４Ａ、５Ａ、６Ａ、７Ａ、８族、特に、ランタン、ジル
コニウム、セリウムおよびリチウム、ナトリウム、カリ
ウム、ベリリウム、マグネシウム、カルシウムなどのハ
ロゲン化物および有機酸、無機酸などとの水溶性の塩を
指す。好適には硝酸塩、酢酸塩などである。混合により
この溶液は基体表面近傍もしくは細孔中の極限られた領
域に浸み渡り、閉じ込められた状態となる。(Third Invention) In the method for producing a composite oxide-supported catalyst carrier of the present invention, a solution prepared by dissolving the transition metal, aluminum, alkaline earth metal or alkali metal salt prepared in the first step is used in the third step. And a substrate having pores. The salt refers to 1A, 2A, 1B, 2B, 3A of the second, third, fourth, fifth and sixth periods of the periodic table.
Group 4A, 5A, 6A, 7A, 8 refers to lanthanum, zirconium, cerium and halides such as lithium, sodium, potassium, beryllium, magnesium, calcium and the like, and water-soluble salts with organic acids, inorganic acids and the like. Preferred are nitrates and acetates. Due to the mixing, this solution permeates into the vicinity of the substrate surface or a very limited area in the pores, and becomes a trapped state.
【００３３】その後、第４工程において限られた領域に
閉じ込められたの溶液に沈殿発生剤を添加し急速に酸化
物前駆体の共沈が始まるpH域に変化させる。この時、塩
が閉じ込められた極小さな限られた領域ではその吸着作
用によりpHの変化がさらに急激に全体に渡って生じ、極
小さな限られた領域に閉じ込められた塩は粒子成長があ
まり起きず、高分散状態で沈殿する。複数種の酸化物前
駆体が溶液に含まれている場合にはマイクロカプセル内
固有の特性として個々のpH沈殿特性にかかわらず同時に
沈殿を発生し複数の酸化物前駆体が高度に分散した沈殿
物が得られる。これを酸化物に変換すれば分散性のよい
微粒子状の複合酸化物が得られる。Thereafter, a precipitation generating agent is added to the solution confined in the limited region in the fourth step to change the solution to a pH region where coprecipitation of the oxide precursor starts rapidly. At this time, in the extremely small limited area where the salt is confined, the change in pH occurs more rapidly over the entire area due to the adsorption action, and the salt confined in the very small limited area does not cause much particle growth. Precipitates in a highly dispersed state. When multiple types of oxide precursors are contained in a solution, precipitates are generated simultaneously regardless of individual pH precipitation characteristics as a unique property in the microcapsule, and a precipitate in which multiple oxide precursors are highly dispersed Is obtained. By converting this into an oxide, a finely divided composite oxide having good dispersibility can be obtained.
【００３４】本発明の方法によれば、細孔を有する基体
の表面あるいは細孔内に複数の酸化物が高度に分散した
触媒担持用担体を作製することができる。本発明の方法
によって細孔を有する基体に担持された複合酸化物は、
その粒子径が十分に小さく細孔の閉塞が生じない。従っ
て、得られた触媒担持用担体の表面積の低下が少なく、
担持した複合酸化物の助触媒としての能力が十分に発揮
され、さらに触媒を担持した時には触媒の作用が最大限
に発揮される。According to the method of the present invention, it is possible to prepare a catalyst-carrying carrier in which a plurality of oxides are highly dispersed on the surface of a substrate having pores or in pores. The composite oxide supported on the substrate having pores according to the method of the present invention,
The particle size is sufficiently small so that pores are not blocked. Therefore, a decrease in the surface area of the obtained catalyst-supporting carrier is small,
The capacity of the supported composite oxide as a cocatalyst is sufficiently exhibited, and when the catalyst is supported, the action of the catalyst is maximized.
【００３５】（第４発明）基体が第３発明の塩の溶液と
反応すると沈殿反応が徐々に進行し沈殿粒子が大きく成
長（２次粒子の成長）するので高分散状態の沈殿物が得
られない。溶解した塩の内の特定の種類のものが基体と
反応して酸化物前駆体の沈殿を発生すると、次の過程で
複数種の酸化物前駆体の沈殿を発生させても沈殿物は遍
析が生じたものと同じ結果となり、複数の酸化物が高度
に分散した複合酸化物を作製できない。このため、本発
明では基体と酸化物前駆体との反応性を低下させるため
に基体に処理を施す。この処理工程では酸化物前駆体発
生溶液に対し、沈殿を自然に誘発するような基体表面の
物理的あるいは化学的活性を低下させる。(Fourth Invention) When the substrate reacts with the salt solution of the third invention, the precipitation reaction proceeds gradually, and the precipitated particles grow large (the growth of secondary particles), so that a highly dispersed precipitate is obtained. Absent. When a specific type of dissolved salt reacts with the substrate and precipitates an oxide precursor, the precipitate is omnipresent even if a plurality of types of oxide precursors are precipitated in the following process. The result is the same as that in which occurs, and a composite oxide in which a plurality of oxides are highly dispersed cannot be produced. For this reason, in the present invention, the substrate is treated to reduce the reactivity between the substrate and the oxide precursor. In this treatment step, the physical or chemical activity of the substrate surface that naturally induces precipitation in the oxide precursor generation solution is reduced.
【００３６】スラリーの分散媒、たとえば水、と酸化物
前駆体発生用の塩を溶解させた溶媒とに親和性があれば
このスラリーと塩の溶液とはよく混合する。また、スラ
リーの分散媒はその種類により予め基体の細孔内に浸透
するので、第３工程においてスラリーと塩の溶液とを混
合したとき塩の溶液が基体マイクロカプセル内へ浸透す
る量を調節し、析出した酸化物前駆体の沈殿の分散化・
微粒子化を促進する。If there is an affinity for the dispersion medium of the slurry, for example, water, and the solvent in which the salt for generating the oxide precursor is dissolved, the slurry and the salt solution are mixed well. Further, since the dispersion medium of the slurry permeates into the pores of the substrate in advance depending on the type, the amount of the salt solution permeating into the substrate microcapsules when the slurry and the salt solution are mixed in the third step is adjusted. Dispersion of precipitate of precipitated oxide precursor
Promotes micronization.
【００３７】反応性が抑制された基体を流動性のあるス
ラリーとすることにより遷移金属、アルミニウム、アル
カリ土類金属あるいはアルカリ金属の塩の溶液との混合
が容易になり、遷移金属塩の溶液が基体細孔内および基
体表面の極近傍へ十分に行き渡る。また、担持酸化物と
基体との分散性を調節することができる。By making the substrate with reduced reactivity into a fluid slurry, it becomes easy to mix with a transition metal, aluminum, alkaline earth metal or alkali metal salt solution, and the transition metal salt solution becomes It spreads well in the pores of the substrate and very near the surface of the substrate. Further, the dispersibility between the supported oxide and the substrate can be adjusted.
【００３８】（第５発明）本発明の方法により、セリア
およびジルコニアが基体上に極微細な状態で高分散に担
持され、良好な固溶体を形成する。セリアおよびジルコ
ニアが基体上に極微細な状態で高分散に担持されるた
め、セリアにより付加された担体の酸素吸蔵能を最大限
に発揮させることができ、さらにジルコニアによるセリ
アの耐熱性向上も十分に図ることができる。(Fifth Invention) According to the method of the present invention, ceria and zirconia are supported on a substrate in a very fine state in a highly dispersed state, and a good solid solution is formed. Since ceria and zirconia are supported in a very fine state on the substrate in a highly dispersed state, the oxygen storage capacity of the carrier added by ceria can be maximized, and the improvement of the heat resistance of ceria by zirconia is sufficient. It can be aimed at.
【００３９】（第６発明）La もしくはBa安定化アルミ
ナは水浸pHが高く、弱アルカリ性を示すため第２工程に
おいて硝酸または酢酸などによりあらかじめ酸性側にpH
調整しないと水酸化セリウムより先に水酸化ジルコニウ
ムが沈殿してしまいセリアとジルコニアを高度に分散さ
せることができない。しかし、本発明の方法により、水
酸化セリウム、水酸化ジルコニウムが La もしくはBa安
定化アルミナ基体の細孔内および／またはアルミナ２次
粒子の表面の近傍の粒界部などに同時に、遍析のない状
態で析出する。(Sixth invention) La or Ba stabilized alumina has a high water immersion pH and shows weak alkalinity.
If not adjusted, zirconium hydroxide precipitates before cerium hydroxide, so that ceria and zirconia cannot be highly dispersed. However, according to the method of the present invention, cerium hydroxide and zirconium hydroxide are not lumped at the same time in the pores of the La or Ba stabilized alumina substrate and / or in the grain boundaries near the surface of the alumina secondary particles. Precipitates in a state.
【００４０】これは図１に示すpH 滴定曲線において、
硝酸セリウム水溶液をアンモニア水で滴定した曲線１、
硝酸ジルコニル水溶液をアンモニア水で滴定した曲線
２、もしくは両塩の混合溶液の滴定曲線３にあった変化
に対応した変化が消失し、アルミナ共存下で行った場合
には曲線４に示すようななめらかな曲線になることから
も推察される。これにより触媒担体として優れた特性を
持つLaもしくはBa安定化アルミナ基体上に、セリアおよ
びジルコニアが高度に分散した極微細な高分散状態さら
には固溶状態で担持される。[0040] This is the pH titration curve shown in FIG. 1,
Curve 1 obtained by titrating an aqueous cerium nitrate solution with aqueous ammonia,
Curve of titrated aqueous solution of zirconyl nitrate with aqueous ammonia
2 or when the change corresponding to the change in the titration curve 3 of the mixed solution of both salts disappears and the test is performed in the presence of alumina.
Can be inferred from the fact that a smooth curve as shown by curve 4 is obtained. As a result, on a La or Ba stabilized alumina substrate having excellent properties as a catalyst carrier, ceria and zirconia are supported in a very fine, highly dispersed state and a solid solution state in which ceria and zirconia are highly dispersed.
【００４１】図２のＸ線回折測定結果に示されるように
本発明によって担持されたセリア−ジルコニア複合酸化
物はもとのセリア（回折線５）およびジルコニア（回折
線６）の回折線とは異なる新たな回折線（回折線８）を
生じる。従来法ではセリアとジルコニアが２相に分離す
る（回折線７）。回折線８はジルコニアがセリアに高度
に固溶した固溶体の生成を意味し、１次粒子（Ｘ線的な
意味での粒子）径の小さな複合体ができたことを示して
いる。本発明によって得られた複合酸化物担持触媒担体
はセリアおよびジルコニアが極微細な固溶体として、基
体上に高分散状態で担持され、また、基体細孔の閉塞が
生じない。従って、できた触媒担持用担体の表面の低下
が少ないため、セリアにより付加された担体の酸素吸蔵
能を最大限に発揮させることができる。さらに、ジルコ
ニアによるセリアの耐熱性向上も十分に図ることができ
る。As shown in the X-ray diffraction measurement results in FIG. 2, the ceria-zirconia composite oxide supported by the present invention is different from the original ceria (diffraction line 5) and zirconia (diffraction line 6) diffraction lines. A different new diffraction line (diffraction line 8) results. In the conventional method, ceria and zirconia separate into two phases (diffraction line 7). Diffraction line 8 indicates the formation of a solid solution in which zirconia is highly dissolved in ceria, and indicates that a composite having a small primary particle (particle in the X-ray sense) diameter was formed. The composite oxide-carrying catalyst carrier obtained by the present invention has ceria and zirconia supported as a very fine solid solution on the substrate in a highly dispersed state, and does not block the pores of the substrate. Therefore, since the surface of the resulting catalyst-supporting carrier is less reduced, the oxygen storage capacity of the carrier added by ceria can be maximized. Furthermore, the heat resistance of ceria can be sufficiently improved by zirconia.
【００４２】（第７発明）本発明の工程により、遷移金
属、アルミニウム、アルカリ土類金属あるいはアルカリ
金属の酸化物前駆体である水酸化物が複数種、マイクロ
カプセル内において高分散状態の微粒子として共沈す
る。細孔を有する基体の表面あるいは細孔内に遷移金属
の酸化物が高度に分散した触媒担持用担体を作製するこ
とができる。従って、これら水酸化物を酸化物に変換し
た場合、細孔を有する基体に微粒子状の複合酸化物助触
媒が高度に分散する。従って、担持した複合酸化物の粒
子が十分に小さいため基体細孔の閉塞が生じず、できた
触媒担持用担体の表面積の低下が少ない。このため、複
合酸化物の助触媒としての能力が十分に発揮され、その
後、触媒を担持した時には複合酸化物助触媒の効果によ
り触媒の作用が最大限に発揮される。(Seventh Invention) According to the process of the present invention, a plurality of types of hydroxides, which are oxides of transition metals, aluminum, alkaline earth metals or alkali metals, are obtained as fine particles in a highly dispersed state in microcapsules. Co-precipitate. A catalyst-carrying support in which a transition metal oxide is highly dispersed on the surface of a substrate having pores or in pores can be produced. Therefore, when these hydroxides are converted to oxides, the particulate composite oxide promoter is highly dispersed in the substrate having pores. Therefore, since the supported composite oxide particles are sufficiently small, the pores of the base are not blocked, and the decrease in the surface area of the resulting catalyst-supporting carrier is small. For this reason, the ability of the composite oxide as a co-catalyst is sufficiently exhibited, and when the catalyst is subsequently supported, the effect of the catalyst is maximized by the effect of the composite oxide co-catalyst.
【００４３】（第８発明〜第１３発明）セリアとジルコ
ニアが原子レベルでほぼ均一に分散するため、ジルコニ
アがセリアの凝集を防止し、その耐熱性が十分に向上す
る。また、分散性が適度であるため、セリアが後に担持
された触媒と十分にコンタクトすることができ、その助
触媒効果が十分に発揮される。また、同時に担体とセリ
アとの反応による凝集も防止できる。従って、ジルコニ
アのセリア助触媒能に対する阻害効果が少ない。(Eighth to thirteenth inventions) Since ceria and zirconia are substantially uniformly dispersed at the atomic level, zirconia prevents aggregation of ceria and its heat resistance is sufficiently improved. In addition, since the dispersibility is appropriate, ceria can be sufficiently contacted with a catalyst which is later supported, and the cocatalyst effect is sufficiently exhibited. At the same time, aggregation due to the reaction between the carrier and ceria can be prevented. Therefore, the effect of zirconia on ceria promoter activity is small.
【００４４】ジルコニアの耐熱効果が十分に発揮され、
高温下および高温履歴後でもセリアの酸素吸蔵能が最大
限に発揮される。固溶体状態の複合化なのでセリアの耐
熱性がよくその助触媒効果がよく発揮される。本発明の
製造方法で作製された酸化物担持担体は1000℃以上の高
温耐熱試験後でも担体として良好な特性を有している。
900 ℃以下の高温履歴に対して十分な耐性を有している
ことはもちろんである。The heat-resistant effect of zirconia is fully exhibited,
The oxygen storage capacity of ceria is maximized even at high temperatures and after a history of high temperatures. Since it is a composite in a solid solution state, the heat resistance of ceria is good and its cocatalyst effect is well exhibited. The oxide-carrying carrier produced by the production method of the present invention has good properties as a carrier even after a high temperature heat test at 1000 ° C. or higher.
Needless to say, it has sufficient resistance to a high temperature history of 900 ° C. or less.
【００４５】（第１４発明）ジルコニア（La、Ce、Ca、
Ba、Mgなどの希土類あるいはアルカリ土類さらにアルミ
ニウムを安定化材として含んでもよい）をアルミナ、シ
リカ、ジルコニア等の担体に担持、あるいはそれ自体を
貴金属の担体として用いることにより、Rhとアルミナと
の反応を防止し、高温使用条件下でRhの活性を維持でき
る。担体表面に微細なジルコニアを担持、あるいは複合
化（貴金属を担持したアルミナ層と、Rhを担持したジル
コニアを主成分とした層の二層コートにすることもでき
る。）することによって、貴金属特にRhと担体との高温
での固相反応が抑制される。酸化ジルコニウムの担持量
が４％未満の場合には上記の耐熱性効果が発揮されな
い。担持量が９５％を越えると貴金属の触媒作用が低下
し始める。担体表面に微細なジルコニアを担持すること
によって貴金属と担体、特にアルミナとの高温での固相
反応を抑制することができる。(14th invention) Zirconia (La, Ce, Ca,
A rare earth or alkaline earth such as Ba, Mg or the like, and aluminum may be contained as a stabilizing material) on a carrier such as alumina, silica, or zirconia, or by using itself as a carrier of a noble metal, Rh and alumina The reaction can be prevented and the activity of Rh can be maintained under high temperature use conditions. Noble metals, especially Rh, can be supported or supported by fine zirconia on the surface of the support (a two-layer coating of an alumina layer supporting noble metals and a layer mainly containing zirconia supporting Rh). The solid-state reaction between the and the carrier at a high temperature is suppressed. When the loading amount of zirconium oxide is less than 4%, the above-mentioned heat resistance effect is not exhibited. If the supported amount exceeds 95%, the catalytic action of the noble metal starts to decrease. By supporting fine zirconia on the surface of the carrier, a high-temperature solid-state reaction between the noble metal and the carrier, particularly alumina, can be suppressed.
【００４６】[0046]
【実施例】以下、本発明を実施例により説明する。本実
施例で調製した酸化物担持触媒担体の一覧を表１に示
す。The present invention will be described below with reference to examples. Table 1 shows a list of the oxide-carrying catalyst carriers prepared in this example.
【００４７】[0047]
【表１】 [Table 1]
【００４８】（実施例１）活性アルミナ担体１２０ｇに
対して、担持するセリアとジルコニアの合計の担持量が
０.３mol になる酸化物担持活性アルミナ担体 Ａ を
次のように作製した。(Example 1) An oxide-supported activated alumina carrier A in which the total amount of ceria and zirconia carried per 120 g of the activated alumina carrier was 0.3 mol was prepared as follows.
【００４９】第１工程として水0.6l に対して加える硝
酸塩の合計モル数が０.３mol になるように、硝酸セリ
ウムと硝酸ジルコニル水和物の混合水溶液を調製した。
第２工程として平均二次粒子径を数μｍとした市販の活
性アルミナ１２０ｇを工程１の混合水溶液に徐々に添加
し、水浸ｐＨが酸性を示すようにｐＨ調製し、懸濁液を
調製した。さらに、第１工程において調製した溶液中の
硝酸塩に対する１. ２倍等量のアンモニア水を溶かした
水溶液（中和剤）約0.29l を調製した。In the first step, a mixed aqueous solution of cerium nitrate and zirconyl nitrate hydrate was prepared so that the total number of moles of nitrate added to 0.6 l of water was 0.3 mol.
As a second step, 120 g of commercially available activated alumina having an average secondary particle diameter of several μm was gradually added to the mixed aqueous solution of step 1, and the pH was adjusted so that the water immersion pH was acidic to prepare a suspension. . Further, about 0.29 l of an aqueous solution (neutralizing agent) prepared by dissolving 1.2 times as much ammonia water as nitrate in the solution prepared in the first step was prepared.
【００５０】第３工程として第２工程で調製した混合液
に、第２工程で調製した中和剤を１分以内に添加し均一
に撹はんし沈澱をおこさせた。その後この懸濁液をろ過
し、１００℃にて２０ｈｒ乾燥した。第４工程として７
５０℃で３ｈｒ、大気中にて焼成し、沈澱により生成し
た水酸化物を酸化物に変換し、酸化物担持活性アルミナ
担体 Ａ を調製した。As a third step, the neutralizing agent prepared in the second step was added to the mixed solution prepared in the second step within one minute, and the mixture was uniformly stirred to cause precipitation. Thereafter, the suspension was filtered and dried at 100 ° C. for 20 hours. 7 as the fourth step
The resultant was calcined at 50 ° C. for 3 hours in the air, and the hydroxide generated by precipitation was converted into an oxide, whereby an oxide-supported activated alumina carrier A was prepared.
【００５１】Ａの作製工程中の第２工程において、硝酸
水溶液をしみ込ませることにより酸性化した、市販の中
性またはアルカリ性の活性アルミナ担体を用いたこと以
外Ａの作製工程と同様の方法で活性アルミナ担体 Ｂ
を作製した。In the second step of the preparation process of A, the activity was activated in the same manner as in the preparation process of A except that a commercially available neutral or alkaline activated alumina carrier acidified by impregnation with a nitric acid aqueous solution was used. Alumina carrier B
Was prepared.
【００５２】Ａの作製工程から中和・沈殿処理を除いた
以外は全く同じ処理液による含浸法によって比較例
（Ａ）の酸化物担持担体を作製した。また、活性アルミ
ナ担体１２０ｇに対して、担持するセリアとジルコニア
粉末の合計の添加量が０. ３molになる様に酸化物粉末
を添加し、らいかい機による混合を行うことによる粉末
添加法により酸化物担持活性アルミナ担体((Ａ))を調製
した。結果を表２に示す。The oxide-carrying carrier of Comparative Example (A) was prepared by the same impregnation method using the same processing solution except that the neutralization / precipitation treatment was omitted from the preparation process of A. Also, an oxide powder was added to 120 g of the activated alumina carrier so that the total added amount of the ceria and zirconia powders to be supported was 0.3 mol, and the mixture was mixed by a grinder and oxidized by a powder addition method. An activated alumina carrier ((A)) was prepared. Table 2 shows the results.
【００５３】[0053]
【表２】 [Table 2]
【００５４】ここでは、酸化物担持担体の比表面積、セ
リア粒子径、セリア中へのジルコニウム固溶量、セリア
の分散性、およびＯＳＣ評価を行った。表中のＡ、Ｂか
らわかるように本実施例の方法によりセリアの分散性の
高い担体が得られた。この担体は耐熱試験後においても
十分小さなセリア粒子径を有しており、耐熱性の良好な
担体といえる。Here, the specific surface area of the oxide-carrying carrier, the ceria particle diameter, the amount of zirconium dissolved in ceria, the dispersibility of ceria, and the OSC were evaluated. As can be seen from A and B in the table, a carrier with high dispersibility of ceria was obtained by the method of this example. This carrier has a sufficiently small ceria particle diameter even after the heat test, and can be said to be a carrier having good heat resistance.
【００５５】（実施例２）活性アルミナ担体１２０ｇに
対して、担持するセリアとジルコニアおよびカルシアの
合計の担持量が０. ３mol になる酸化物担持活性アルミ
ナ担体 Ｃ を次のように作製した。Example 2 An oxide-carrying activated alumina carrier C in which the total amount of ceria, zirconia and calcia carried was 0.3 mol per 120 g of the activated alumina carrier was prepared as follows.
【００５６】第１工程として水0.6 l に対して加える硝
酸塩の合計モル数が０. ３mol になるように、硝酸セリ
ウムと硝酸ジルコニル水和物および硝酸カルシウムの混
合水溶液を調製した。第２工程として、硝酸水溶液を染
み込ませ酸性にした、平均２次粒子径数μｍのLa安定化
活性アルミナ１２０ｇを工程１の混合水溶液に徐々に添
加し懸濁液を調製した。さらに、第１工程において調製
した溶液中の硝酸塩に対する割合で１. ２倍等量の水酸
化ナトリウムを溶かした水溶液（中和剤）約0.29l を調
製した。In the first step, a mixed aqueous solution of cerium nitrate, zirconyl nitrate hydrate and calcium nitrate was prepared so that the total number of moles of nitrate added to 0.6 l of water was 0.3 mol. In the second step, 120 g of La-stabilized activated alumina having an average secondary particle diameter of several μm and impregnated with an aqueous nitric acid solution was gradually added to the mixed aqueous solution in Step 1 to prepare a suspension. Further, about 0.29 l of an aqueous solution (neutralizing agent) in which 1.2 equivalents of sodium hydroxide was dissolved in a ratio of nitrate in the solution prepared in the first step to 1.2 times was prepared.
【００５７】第３工程として第２工程で調製した混合液
に、第２工程で調製した中和剤を１分以内に添加し均一
に撹はんし沈澱をおこさせた。その後この懸濁液を水洗
ろ過し、１００℃にて２０ｈｒ乾燥した。As a third step, the neutralizing agent prepared in the second step was added to the mixed solution prepared in the second step within 1 minute, and the mixture was uniformly stirred to cause precipitation. Thereafter, the suspension was washed with water, filtered, and dried at 100 ° C. for 20 hours.
【００５８】第４工程として７５０℃で３ｈｒ、大気中
にて焼成することにより、沈澱により生成した水酸化物
を酸化物に変換して酸化物担持活性アルミナ担体 Ｃ
を調製した。Ｃの第２工程において、アルミナ担体を水
に分散させ硝酸を加え、酸性（ｐＨ約５）のスラリー
（懸濁液）とし、これを用いた以外Ｃの調製方法と同様
の製造方法で酸化物担持活性アルミナ担体 Ｄ を作製
した。In the fourth step, the hydroxide produced by precipitation is converted into an oxide by firing at 750 ° C. for 3 hours in the atmosphere to convert the oxide-supported activated alumina carrier C into an oxide.
Was prepared. In the second step of C, the alumina carrier is dispersed in water and nitric acid is added to form an acidic (pH about 5) slurry (suspension). A supported activated alumina support D was prepared.
【００５９】表２からわかるように本実施例の方法によ
って作製した担体Ｃ、Ｄはセリアの分散性が良好である
ことがわかった。この担体は耐熱試験後においても大き
な比表面積と十分小さなセリア粒子径を有しており、耐
熱性の良好な担体といえる。As can be seen from Table 2, it was found that the carriers C and D produced by the method of this example had good ceria dispersibility. This carrier has a large specific surface area and a sufficiently small ceria particle diameter even after the heat resistance test, and can be said to be a carrier having good heat resistance.
【００６０】（実施例３）セリアとジルコニアの固溶割
合の異なるセリア−ジルコニア担持アルミナ担体Ｅ、
Ｆ、Ｇ、Ｈを次のように作製した。第１工程として水0.
6lに対して加える硝酸塩の合計モル数が０. ３mol にな
るように、硝酸セリウムと硝酸ジルコニル水和物の混合
水溶液を調製した。第２工程として、平均２次粒子径を
数μｍとしたＬａまたはＢａ安定化活性アルミナ１２０
ｇを水に分散させ0.6lとした。これに０. ０２６モルの硝
酸を加え、酸性（ｐＨ約５）のスラリー（懸濁液）を調
製した。これにより硝酸塩溶液と混合した時水酸化ジル
コニウムの沈澱が発生し、これがコロイド化するのを防
止させることができる。さらに、第１工程において調製
した硝酸塩に対する割合にして１. ２倍等量のアンモニ
ア水を溶かした水溶液（中和剤）約0.29l を調製した。Example 3 A ceria-zirconia-carrying alumina carrier E having a different solid solution ratio between ceria and zirconia,
F, G, and H were prepared as follows. Water as the first step
A mixed aqueous solution of cerium nitrate and zirconyl nitrate hydrate was prepared such that the total number of moles of nitrate added to 6 l was 0.3 mol. In the second step, La or Ba stabilized activated alumina 120 having an average secondary particle diameter of several μm was used.
g was dispersed in water to make 0.6 l. To this, 0.026 mol of nitric acid was added to prepare an acidic (pH about 5) slurry (suspension). This can prevent the precipitation of zirconium hydroxide when mixed with the nitrate solution, which can be prevented from forming a colloid. Further, about 0.29 l of an aqueous solution (neutralizing agent) in which 1.2 times the amount of aqueous ammonia was dissolved in the nitrate prepared in the first step was prepared.
【００６１】第３工程として第１工程により調製した硝
酸塩水溶液と第２工程で調製した懸濁液を混合し、撹は
ん機により２分間混合した。この撹はん時間の選択によ
り基体細孔内への硝酸塩の拡散量が調整できる。第４工
程として第３工程で調製した混合液に、第２工程で調製
した中和剤を１分以内に添加するとともに、均一に撹は
んし沈澱を発生させた。その後、この懸濁液をろ過し、
１００℃にて２０ｈｒ乾燥させた。As a third step, the aqueous nitrate solution prepared in the first step and the suspension prepared in the second step were mixed, and mixed for 2 minutes by a stirrer. The diffusion amount of nitrate into the pores of the substrate can be adjusted by selecting the stirring time. As a fourth step, the neutralizing agent prepared in the second step was added to the mixture prepared in the third step within 1 minute, and the mixture was stirred uniformly to generate a precipitate. Then, the suspension was filtered,
It was dried at 100 ° C. for 20 hours.
【００６２】第５工程として、７５０℃で３ｈｒ、大気
中にて焼成し、沈澱により生成した水酸化物を酸化物に
変換し、セリア−ジルコニア担持アルミナ担体Ｅ、Ｆ、
Ｇ、Ｈを調製した。In the fifth step, calcination is performed at 750 ° C. for 3 hours in the air, and the hydroxide formed by precipitation is converted into an oxide, and the ceria-zirconia-supported alumina carriers E, F,
G and H were prepared.
【００６３】比較例として、硝酸を加えていないｐＨ未
調整のスラリーを用いること以外、上記と全く同じ方法
で、セリアとジルコニアを等量担持した活性アルミナ担
体（Ｉ）を作製した。結果を前記表２および表３に示
す。表３にはこれら担体に白金触媒を担持しその特性値
を測定した結果を示す。As a comparative example, an activated alumina carrier (I) carrying equal amounts of ceria and zirconia was prepared in exactly the same manner as described above, except that a slurry whose pH was not adjusted without adding nitric acid was used. The results are shown in Tables 2 and 3 above. Table 3 shows the results of measuring the characteristic values of platinum carriers supported on these carriers.
【００６４】[0064]
【表３】 [Table 3]
【００６５】表３より本実施例の担体が優れた高温耐熱
特性を有していることがわかる。 ─担体への触媒担持─ これら酸化物担持活性アルミナ担体Ｅ、Ｆ、Ｇ、Ｈを砕
いた後水に分散させスラリー化しミリング後、白金塩に
より白金を含浸担持し、乾燥した。具体的には担体粉末
8 g に硝酸白金を主成分とする白金担持液(白金濃度1g
/500cc)の水溶液約48ccを加えスターラーにより撹はんしなが
ら１４ｈｒ静置し、９０℃で撹はんしながら乾燥し、本
実施例の触媒を得た。白金の担持量としては酸化物担持
活性アルミナ担体中の活性アルミナ１２０ｇに対して２
ｇとした。Table 3 shows that the carrier of this example has excellent high temperature heat resistance. << Catalyst Support on Carrier >> These oxide-supported active alumina carriers E, F, G, and H were crushed, dispersed in water, slurried, milled, platinum-impregnated with a platinum salt, and dried. Specifically, carrier powder
8 g of platinum-supported liquid containing platinum nitrate as the main component (platinum concentration 1 g
/ 500 cc) aqueous solution (about 48 cc) was added, and the mixture was allowed to stand for 14 hours while stirring with a stirrer, and dried at 90 ° C. with stirring to obtain a catalyst of this example. The amount of platinum supported was 2 per 120 g of activated alumina in the oxide-supported activated alumina carrier.
g.
【００６６】また、比較例として担体((Ａ))、( Ａ) 、
Ｉ、Ｋについても上記と同様に白金を担持し比較例の触
媒を作製した。以上のように担体を触媒化する場合、貴
金属の種類や担持量、担持方法および、ハニカム担体へ
のコーティング方法は特に限定されない、たとえば担体
を粉末化した後スラリー化し貴金属を担持する方法や、
酸化物前駆体の沈殿したスラリーを直接金属製あるいは
セラミック製ハニカム担体にコーティング後焼成して作
製した担体に貴金属を吸着、含浸あるいは吸水担持して
も良い。As comparative examples, the carriers ((A)), (A),
Regarding I and K, platinum was carried in the same manner as above to prepare a catalyst of Comparative Example. When the carrier is catalyzed as described above, the type and amount of the noble metal, the amount of the supporting method, and the method of coating the honeycomb carrier are not particularly limited.For example, a method in which the carrier is powdered and then slurried to support the noble metal,
The noble metal may be adsorbed, impregnated, or water-absorbed by a carrier prepared by directly coating a metal or ceramic honeycomb carrier with the slurry in which the oxide precursor has been precipitated and then firing it.
【００６７】ＯＳＣ評価における触媒は、担体を粉末化
した後スラリー化し貴金属を担持する方法や、酸化物前
駆体の沈殿したスラリーを直接金属製あるいはセラミッ
ク製ハニカム担体にコーティング後焼成して作製した担
体に貴金属を吸着、含浸あるいは吸水担持しても良い。
できた触媒粉末を 0.5〜1mm角のペレット状とし、300、
500 、700 ℃の各温度において酸素の飽和吸蔵量を評価
した。表２からわかるように本実施例の方法により作製
した担体はセリアの分散性が良好であることがわかっ
た。この担体は耐熱試験後においても大きな比表面積と
十分小さなセリア粒子径を有しており、耐熱性の良好な
担体といえる。また、比較例（Ｉ）のセリア粒子径は大
きく、基体に対するpH調整の効果が高いことがわかる。In the OSC evaluation, a catalyst is prepared by pulverizing the carrier and then slurrying the carrier to support the noble metal, or by coating the slurry in which the oxide precursor has been precipitated directly on a metallic or ceramic honeycomb carrier and calcining it. A noble metal may be adsorbed, impregnated or carried with water.
The resulting catalyst powder is formed into pellets of 0.5-1 mm square, 300,
At each temperature of 500 and 700 ° C., the saturated storage amount of oxygen was evaluated. As can be seen from Table 2, it was found that the carrier prepared by the method of this example had a good ceria dispersibility. This carrier has a large specific surface area and a sufficiently small ceria particle diameter even after the heat resistance test, and can be said to be a carrier having good heat resistance. In addition, the ceria particle size of Comparative Example (I) is large, and it can be seen that the effect of pH adjustment on the substrate is high.
【００６８】さらに、本実施例の酸化物担持担体に白金
を担持した触媒組織の走査型電子顕微鏡( ＳＥＭ) 写真
を図３に示す。セリアおよびジルコニアの複合酸化物
（写真では白く見える）が、アルミナの２次粒子の粒界
部に分布しており、２次粒子の細孔内部には分布してい
ない状態が確認される。FIG. 3 shows a scanning electron microscope (SEM) photograph of a catalyst structure in which platinum is supported on the oxide-carrying support of this example. It is confirmed that the composite oxide of ceria and zirconia (which looks white in the photograph) is distributed at the grain boundary portion of the secondary particles of alumina and not distributed inside the pores of the secondary particles.
【００６９】( 実施例４）実施例３の第４工程におい
て、中和剤を３分以内で添加すること以外、実施例３と
全く同様の方法で、セリアとジルコニアを等量担持した
活性アルミナ担体Ｊを作製した。Example 4 Activated alumina loaded with equal amounts of ceria and zirconia in the same manner as in Example 3 except that in the fourth step of Example 3, a neutralizing agent was added within 3 minutes. Carrier J was produced.
【００７０】比較例として中和剤を１０分間、じょじょ
に添加したこと以外、上記と全く同様の方法で、セリア
とジルコニアを等量担持した活性アルミナ担体（Ｋ）を
作製した。表２からわかるように本実施例の方法により
作製した担体はセリアの分散性が良好であることがわか
った。この担体は耐熱試験後においても大きな比表面積
と十分小さなセリア粒子径を有しており、耐熱性の良好
な担体といえる。また、比較例（Ｋ）のセリア粒子径は
大きく、本実施例のように中和剤を急速に加えることが
効果的であることがわかる。As a comparative example, an activated alumina carrier (K) carrying an equal amount of ceria and zirconia was prepared in exactly the same manner as described above, except that the neutralizing agent was slowly added for 10 minutes. As can be seen from Table 2, it was found that the carrier prepared by the method of this example had a good ceria dispersibility. This carrier has a large specific surface area and a sufficiently small ceria particle diameter even after the heat resistance test, and can be said to be a carrier having good heat resistance. In addition, the ceria particle diameter of Comparative Example (K) is large, and it is found that it is effective to rapidly add the neutralizing agent as in this example.
【００７１】（実施例５）前記実施例３の第３工程にお
いて、撹はん機により１０分間、塩を溶解した溶液とス
ラリーを混合する以外、実施例３と全く同様の方法で酸
化物担持活性アルミナ担体 Ｌ を調製した。表２から
わかるように本実施例の方法により作製した担体はセリ
アの分散性が良好であることがわかった。この担体は耐
熱試験後においても大きな比表面積と十分小さなセリア
粒子径を有しており、耐熱性の良好な担体といえる。ま
た、本実施例の担体に実施例３と同様の方法により白金
を担持した触媒組織のＳＥＭ(FE-SEM)観察結果を図４に
示す。これより、セリアおよびジルコニアの複合酸化物
が、アルミナの２次粒子の粒界部と、アルミナの２次粒
子の細孔内部にまで分布していることがわかる。(Example 5) In the third step of Example 3, the oxide-supporting method was carried out in exactly the same manner as in Example 3 except that the solution in which the salt was dissolved and the slurry were mixed for 10 minutes using a stirrer. Activated alumina carrier L was prepared. As can be seen from Table 2, it was found that the carrier prepared by the method of this example had a good ceria dispersibility. This carrier has a large specific surface area and a sufficiently small ceria particle diameter even after the heat resistance test, and can be said to be a carrier having good heat resistance. FIG. 4 shows the results of SEM (FE-SEM) observation of a catalyst structure in which platinum was supported on the support of this example by the same method as in Example 3. This indicates that the composite oxide of ceria and zirconia is distributed to the grain boundary portion of the secondary alumina particles and the inside of the pores of the secondary alumina particles.
【００７２】（実施例６）実施例３と同様の方法で作製
された酸化ジルコニウム担持La安定化活性アルミナ担体
において、アルミとジルコニウムの金属原子比がアルミ
ニウム１００に対してジルコニウムが５であり、この担
体中のアルミナ１２０ｇに対して、貴金属としてＰｔを
２ｇとＲｈを０．１５ｇ含浸担持させた酸化ジルコニウ
ム担持La安定化アルミナ触媒 Ｍ を調製した。Example 6 In a zirconium oxide-supported La-stabilized activated alumina carrier produced in the same manner as in Example 3, the metal atom ratio of aluminum to zirconium was 5 with respect to 100 for aluminum and 5 for zirconium. A zirconium oxide-supported La-stabilized alumina catalyst M was prepared by impregnating and supporting 2 g of Pt and 0.15 g of Rh as a noble metal with respect to 120 g of alumina in the support.
【００７３】比較例として酸化ジルコニウムを担持して
いないこと以外は上記触媒と同様の方法でLa安定化アル
ミナ触媒 Ｎ を調製した。以上の触媒を１０００℃で
５ｈｒ大気中にて耐熱試験後、その物性値評価を行っ
た。本実施例の触媒は比較例の触媒に比べて、耐熱試験
後でも白金、ロジウムの触媒活性が低下せず、優れた耐
熱特性を有していることがわかった。As a comparative example, a La-stabilized alumina catalyst N was prepared in the same manner as in the above catalyst except that zirconium oxide was not supported. The above catalyst was subjected to a heat resistance test in the air at 1000 ° C. for 5 hours, and then its physical properties were evaluated. Compared to the catalyst of the comparative example, the catalyst of this example did not decrease in the catalytic activity of platinum and rhodium even after the heat resistance test, and was found to have excellent heat resistance.
【００７４】さらに、本実施例の触媒には、酸化ジルコ
ニウムの安定化のためセリウム、バリウム、カルシウム
等の元素がジルコニウムと同様の方法で担持されていて
も良好な特性が得られる。また、耐熱試験後において、
触媒中のロジウムの一部は白金中に固溶状態として存在
し、一部は酸化ロジウムとして存在していることを、Ｘ
線回折やＸ線光電子分光測定によって確認した。また、
この触媒を３００℃程度のＡ／Ｆ１４．６相当の排気中
にさらしたところ金属状態のロジウムが生成した。この
ことから、本発明の触媒では、担体とロジウムとの反応
が抑制され、触媒使用時に高活性な金属状態のロジウム
が維持されることを確認した。Further, in the catalyst of this embodiment, good characteristics can be obtained even if elements such as cerium, barium and calcium are supported in the same manner as zirconium for stabilizing zirconium oxide. After the heat test,
X indicates that some of the rhodium in the catalyst exists as a solid solution in platinum and some exists as rhodium oxide.
It was confirmed by X-ray diffraction and X-ray photoelectron spectroscopy. Also,
When this catalyst was exposed to an exhaust gas having an A / F of 14.6 at about 300 ° C., rhodium in a metal state was formed. From this, it was confirmed that in the catalyst of the present invention, the reaction between the carrier and rhodium was suppressed, and that rhodium in a highly active metallic state was maintained when the catalyst was used.
【００７５】これに対し、触媒Ｎは耐熱試験後におい
て、触媒中のロジウムの一部が白金中に固溶状態として
存在するがその固溶量は触媒Ｍの場合よりも少なく、ま
た、一部は担体であるアルミナと複合酸化物を形成した
状態であることを、Ｘ線回折やＸ線光電子分光測定によ
って確認した。また、この触媒を３００℃程度のＡ／Ｆ
１４．６相当の排気中にさらしたところ、金属状態のロ
ジウムはほとんど観測されなかった。このことから、触
媒Ｍでは、担体とロジウムとの反応が進行し、高活性な
金属状態のロジウムが減少していることを確認した。On the other hand, in the case of the catalyst N, after the heat resistance test, part of rhodium in the catalyst is present as a solid solution in platinum, but the amount of the solid solution is smaller than that in the case of the catalyst M. It was confirmed by X-ray diffraction and X-ray photoelectron spectroscopy that a composite oxide was formed with alumina as a carrier. Further, this catalyst is used at an A / F of about 300 ° C.
When exposed to an exhaust gas equivalent to 14.6, almost no metallic rhodium was observed. From this, it was confirmed that in the catalyst M, the reaction between the support and rhodium progressed, and rhodium in a highly active metal state was reduced.
【００７６】（実施例７）実施例３の製造方法によって
調製した担体Ｅ、Ｆ、Ｇ、Ｈのそれぞれについて、担体
１００部と、ベーマイト（水酸化アルミニウム）粉末４
部および水１００部をボールミルで３０分間混合ミリン
グした。その後硝酸アルミニウム７部を混合し、さらに
３０分間ミリングしてスラリー１０リットルを調製し
た。このスラリーに容積１．７リットルのコージェライ
ト質からなるハニカム状のモノリス触媒担体基材を１分
間浸せき後引き上げ、空気流によりセル内の余剰なスラ
リーを吹き飛ばし、１００〜１５０℃の空気流中で１時
間乾燥後、６５０℃で１時間焼成した。この操作を２〜
３回繰り返して触媒担持層を持つモノリス担体基材を得
た。(Example 7) For each of the carriers E, F, G, and H prepared by the production method of Example 3, 100 parts of the carrier and boehmite (aluminum hydroxide) powder 4
And 100 parts of water were mixed and milled in a ball mill for 30 minutes. Thereafter, 7 parts of aluminum nitrate were mixed and milled for 30 minutes to prepare 10 liters of slurry. A honeycomb-shaped monolithic catalyst carrier substrate made of cordierite having a capacity of 1.7 liters was immersed in the slurry for 1 minute, pulled up, and the excess slurry in the cell was blown off by an air stream, and the slurry was blown in an air stream at 100 to 150 ° C. After drying for 1 hour, it was baked at 650 ° C. for 1 hour. This operation is
This was repeated three times to obtain a monolithic carrier substrate having a catalyst supporting layer.
【００７７】これを、白金２．６ｇを含む硝酸白金の水
溶液に１ｈｒ浸せきし、空気流によりセル内の余剰な水
を吹き飛ばし、最高温度２５０℃にて１時間乾燥させ
た。その後、ロジウム０．５ｇを含む硝酸ロジウムの水
溶液に１ｈｒ浸せきし空気流によりセル内の余剰な水を
吹き飛ばし、最高温度２５０℃にて１時間乾燥させ、排
気浄化用触媒 Ｏ、Ｐ、Ｑ、Ｒを得た。This was immersed in an aqueous solution of platinum nitrate containing 2.6 g of platinum for 1 hour, and excess water in the cell was blown off by an air flow, followed by drying at a maximum temperature of 250 ° C. for 1 hour. Thereafter, the cell was immersed in an aqueous solution of rhodium nitrate containing 0.5 g of rhodium for 1 hour, and excess water in the cell was blown off by an air flow, dried at a maximum temperature of 250 ° C. for 1 hour, and exhaust purification catalysts O, P, Q, and R I got
【００７８】得られたそれぞれの触媒について、３リッ
トル直列６気筒エンジンの排気系につけ、空燃比（Ａ／
Ｆ）を１４．６、触媒入りガス温度９００℃の条件で２
００時間耐久試験を行った。その耐久試験後のそれぞれ
の触媒について、耐久試験と同一のエンジンを付けた自
動車を用い、モデル的な国内走行状態における、排気中
の有害成分の浄化率を測定した。結果を表４に示す。本
実施例の触媒はいづれも比較例の触媒よりハイドロカー
ボン（ＨＣ）、一酸化炭素（ＣＯ）、窒素酸化物（Ｎ
Ｏ）の浄化率が優れており、耐熱性の良好な触媒が得ら
れたことがわかる。Each of the obtained catalysts was connected to the exhaust system of a 3-liter inline 6-cylinder engine, and the air-fuel ratio (A /
F) was 14.6 and the temperature was 900 ° C.
A 00 hour durability test was performed. For each of the catalysts after the endurance test, the purification rate of harmful components in exhaust gas was measured in a model domestic running state using an automobile equipped with the same engine as in the endurance test. Table 4 shows the results. All of the catalysts of the present embodiment were more hydrocarbon (HC), carbon monoxide (CO), and nitrogen oxide (N
It can be seen that the purification rate of O) was excellent and a catalyst having good heat resistance was obtained.
【００７９】[0079]
【表４】 [Table 4]
【００８０】（実施例８） 実施例３の第４工程後の懸濁液を直接モノリス触媒担体
基材にコーティングすること以外、実施例７と全く同様
の方法にて排気浄化用触媒 Ｓ、Ｔ、Ｕ、Ｖを得た。ま
た、比較例として担体（Ａ）、担体((Ａ))、担体( Ｋ)
を用いること以外実施例７と同様の方法により排気浄化
用触媒（Ｗ）、（Ｘ）、（Ｙ）を得た。これらの触媒に
ついて実施例７と同様の方法で有害成分の浄化率を測定
した。結果を表４に示す。本実施例の触媒はいづれも比
較例の触媒よりハイドロカーボン（ＨＣ）、一酸化炭素
（ＣＯ）、窒素酸化物（ＮＯ）の浄化率が優れており、
耐熱性の良好な触媒が得られたことがわかる。Example 8 Exhaust gas purification catalysts S and T were prepared in exactly the same manner as in Example 7 except that the suspension after the fourth step of Example 3 was directly coated on the monolith catalyst carrier substrate. , U and V were obtained. Further, as comparative examples, carrier (A), carrier ((A)) , carrier (K)
Exhaust gas purification catalysts (W), (X), and (Y) were obtained in the same manner as in Example 7 except that The purification rate of harmful components of these catalysts was measured in the same manner as in Example 7. Table 4 shows the results. Each of the catalysts of the present embodiment has a higher purification rate of hydrocarbon (HC), carbon monoxide (CO), and nitrogen oxide (NO) than the catalyst of the comparative example.
It can be seen that a catalyst having good heat resistance was obtained.
【図１】ｐＨ変化により沈殿を発生させた時の溶液のｐ
Ｈ変化を示す線図である。FIG. 1 shows the p value of a solution when a precipitate is generated by a change in pH.
It is a diagram which shows H change.
【図２】セリア、ジルコニアおよび両者の固溶体のＸ線
回折パターンを示す線図である。FIG. 2 is a diagram showing an X-ray diffraction pattern of ceria, zirconia, and a solid solution of both.
【図３】実施例３の白金を担持した触媒の断面構造を示
す走査型電子顕微鏡（ＳＥＭ）写真である。FIG. 3 is a scanning electron microscope (SEM) photograph showing a cross-sectional structure of a platinum-supported catalyst of Example 3.
【図４】実施例５の白金を担持した触媒の断面構造を示
す走査型電子顕微鏡（ＳＥＭ）写真である。FIG. 4 is a scanning electron microscope (SEM) photograph showing a cross-sectional structure of a platinum-supported catalyst of Example 5.
１ 硝酸セリウム水溶液をアンモニア水で滴定した結果 ２ 硝酸ジルコニル水溶液をアンモニア水で滴定した結
果 ３ 硝酸セリウムと硝酸ジルコニルとの混合水溶液をア
ンモニア水で滴定した結果 ４ 硝酸セリウムと硝酸ジルコニルとの混合水溶液に、
硝酸によりｐＨ調整したLa安定化活性アルミナのスラリ
ーを加え、撹はんしながらアンモニア水で滴定した結果 ５ セリアのＸ線回折線 ６ ジルコニア単斜晶のＸ線回折線 ７ 従来法により担持したセリア、ジルコニアの２相の
Ｘ線回折線 ８ 本実施例により担持したセリア、ジルコニア単相の
Ｘ線回折線1 Result of titration of cerium nitrate aqueous solution with ammonia water 2 Result of titration of aqueous zirconyl nitrate solution with ammonia water 3 Result of titration of mixed aqueous solution of cerium nitrate and zirconyl nitrate with aqueous ammonia 4 Result of titration of mixed aqueous solution of cerium nitrate and zirconyl nitrate ,
A slurry of activated La-stabilized alumina adjusted to pH with nitric acid was added, and titrated with aqueous ammonia with stirring. 5 X-ray diffraction line of ceria 6 X-ray diffraction line of zirconia monoclinic 7 Ceria supported by conventional method X-ray diffraction line of two phases of zirconia and zirconia 8 X-ray diffraction line of single phase of ceria and zirconia supported by this example
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ Ｂ０１Ｊ 37/02 ３０１ Ｂ０１Ｊ 23/56 ３０１Ａ 37/03 Ｂ０１Ｄ 53/36 Ｃ (56)参考文献 特開 平５−220394（ＪＰ，Ａ) 特開 昭63−116741（ＪＰ，Ａ) 特開 平５−253495（ＪＰ，Ａ) 特開 昭52−41189（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) B01J 21/00 - 38/74 B01D 53/86 B01D 53/94 ──────────────────────────────────────────────────の Continuation of front page (51) Int.Cl. 7 Identification code FI B01J 37/02 301 B01J 23/56 301A 37/03 B01D 53/36 C (56) References JP-A-5-220394 (JP, A) JP-A-63-116741 (JP, A) JP-A-5-253495 (JP, A) JP-A-52-41189 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) ) B01J 21/00-38/74 B01D 53/86 B01D 53/94
Claims (14)
化物担持触媒担体の製造方法において、 沈殿により遷移金属、アルミニウム、アルカリ土類金属
あるいはアルカリ金属から選ばれたセリウムを含む少な
くとも１つの元素の酸化物前駆体を生成する溶液を調製
する第１工程と、 細孔を有する基体と該第１工程の溶液との反応を防止す
るために該基体の該溶液に対する反応性を低下させる処
理を該基体に施す第２工程と、 該第１工程により調製された溶液と該第２工程により反
応性を低下させた基体とを混合してスラリーとする第３
工程と、 該第３工程における該溶液と該基体の混合後10分以内で
混合溶液に該酸化物前駆体の沈殿もしくは共沈を発生さ
せる沈殿発生処理を施し、該基体表面近傍および／また
は該基体の細孔内で該酸化物前駆体を沈殿もしくは共沈
させる第４工程と、 該沈殿もしくは共沈した該酸化物前駆体を酸化物に変換
させる第５工程とからなり、900 ℃の空気中において５
時間以上加熱した時の酸化セリウム粒子径が10nm以下で
ある特性をもつ酸化物担持触媒担体の製造方法。1. A method for producing an oxide-supported catalyst carrier having an oxide supported on a substrate having fine pores, comprising a step of precipitating a small amount of cerium selected from transition metals, aluminum, alkaline earth metals or alkali metals. A first step of preparing a solution that produces an oxide precursor of at least one element; and a step of preparing a solution of the substrate for preventing the reaction between the substrate having pores and the solution of the first step. A second step of subjecting the substrate to a process of reducing reactivity, and a third step of mixing the solution prepared in the first step with the substrate having reduced reactivity in the second step to form a slurry .
Subjecting the mixed solution to precipitation or coprecipitation of the oxide precursor within 10 minutes after the mixing of the solution and the substrate in the third step; a fourth step of precipitating or coprecipitating the oxide precursor within the pores of the substrate, Ri Do and a fifth step of converting the oxide precursors precipitate or coprecipitate to oxide, the 900 ° C. 5 in the air
Cerium oxide particle size when heated for more than 10 hours
A method for producing an oxide-carrying catalyst carrier having certain characteristics .
１記載の酸化物担持触媒担体の製造方法。2. The method according to claim 1, wherein the second step is a pH adjusting step.
金属あるいはアルカリ金属から選ばれ少なくともセリウ
ムを含む２種以上の元素の塩を溶解した溶液を調製する
第１工程と、 細孔を有する基体のpHを調整する第２工程と、 該第１工程の溶液と該第２工程後の基体とを混合してス
ラリーとする第３工程と、 該第３工程後の混合溶液のpHを沈殿発生剤を用いて数分
以内で急速に該２種以上の元素の酸化物前駆体の共沈が
始まるpH域に変化させ、該２種以上の元素の酸化物前駆
体の共沈を発生させる第４工程と、 該共沈した酸化物前駆体を複合酸化物に変換させる第５
工程とからなり、900 ℃の空気中において５時間以上加
熱した時の酸化セリウム粒子径が10nm以下である特性を
もつ酸化物担持触媒担体の製造方法。3. At least cerium selected from transition metals, aluminum, alkaline earth metals or alkali metals.
A step of preparing a solution in which a salt of two or more elements containing a solution is dissolved, a second step of adjusting the pH of the substrate having pores, and a step of: Mix with substrate
A third step to be a rally, and the pH of the mixed solution after the third step is brought to a pH range at which coprecipitation of the oxide precursor of the two or more elements starts rapidly within several minutes using a precipitation generator. A fourth step of causing a co-precipitation of the oxide precursor of the two or more elements by changing the oxide precursor, and a fifth step of converting the co-precipitated oxide precursor into a composite oxide.
Step and Ri Do from pressurized over 5 hours at 900 ° C. in air
The characteristic that the cerium oxide particle diameter when heated is 10 nm or less
For producing an oxide-carrying catalyst carrier.
びジルコニウムの硝酸塩を、前記基体としてアルミナを
用い、酸化セリウムと酸化ジルコニウムの固溶体を担持
した担体を得る請求項３記載の酸化物担持触媒担体の製
造方法。4. The oxide-carrying catalyst carrier according to claim 3 , wherein a carrier carrying a solid solution of cerium oxide and zirconium oxide is obtained by using cerium and zirconium nitrate as the two or more elements and alumina as the substrate. Production method.
化したアルミナを用いる請求項４記載の酸化物担持触媒
担体の製造方法。5. The method for producing an oxide-supported catalyst carrier according to claim 4, wherein alumina stabilized with La or Ba is used as the alumina.
らpH７への変化を数分以内で急速に行う請求項３〜５の
いづれかに記載された酸化物担持触媒担体の製造方法。6. The method for producing an oxide-supported catalyst carrier according to claim 3 , wherein the change in pH in the fourth step is a rapid change from pH 1 to pH 7 within several minutes.
セリウムの合計に対する原子比で10% 以上、80% 以下含
有されてなる請求項５記載の酸化物担持触媒担体の製造
方法によって製造された酸化物担持触媒担体。7. The oxide-supported catalyst produced by the method for producing an oxide-supported catalyst carrier according to claim 5, wherein the cerium is contained in an atomic ratio of 10% or more and 80% or less with respect to the total of the zirconium and the cerium. Catalyst carrier.
少なくとも１種以上の貴金属元素を担持した排ガス浄化
用触媒。8. An exhaust gas purifying catalyst comprising at least one noble metal element supported on the oxide-supported catalyst carrier according to claim 7 .
した時の表面積が80ｍ2 /g以上である請求項８記載の排
ガス浄化用触媒。9. The exhaust gas purifying catalyst according to claim 8 , wherein the catalyst has a surface area of 80 m 2 / g or more when heated in air at 900 ° C. for 5 hours or more.
持触媒担体に含まれる酸化セリウム粒子径が８nm以下で
ある特性をもつ請求項１もしくは請求項３に記載の酸化
物担持触媒担体の製造方法。 10. The oxide carrier after firing at 1000 ° C. for 5 hours.
The cerium oxide particle diameter contained in the supported catalyst carrier is 8 nm or less.
An oxidation according to claim 1 or claim 3 having certain properties.
A method for producing a product-supported catalyst carrier.
持触媒担体に含まれる酸化セリウム粒子径が 5.6〜８nm
である特性をもつ請求項１もしくは請求項３に記載の酸
化物担持触媒担体の製造方法。 11. The oxide carrier after firing at 1000 ° C. for 5 hours.
Cerium oxide particle diameter contained in supported catalyst carrier is 5.6-8nm
An acid according to claim 1 or claim 3 having the following properties:
For producing a compound-carrying catalyst carrier.
と前記セリウムの合計に対する原子比で20% 以上 60%以
下である請求項７記載の酸化物担持触媒担体。12. The oxide-supported catalyst carrier according to claim 7, wherein said zirconium has an atomic ratio of not less than 20% and not more than 60% with respect to the total of said zirconium and said cerium.
と前記セリウムの合計に対する原子比で40% 以上 55%以
下である請求項７記載の酸化物担持触媒担体。13. The oxide-supported catalyst carrier according to claim 7, wherein the zirconium has an atomic ratio of 40% or more and 55% or less with respect to the total of the zirconium and the cerium.
て、前記第１工程の選択元素として少なくともジルコニ
ウムを用いることによって製造された酸化物担持触媒担
体中のジルコニウムの量が前記基体に対する金属の原子
比で４％以上である酸化ジルコニウム担持担体に、さら
にロジウムを担持した排ガス浄化用触媒。14. The method of claim 1 or 3 the method described, the atomic ratio of the metal amount with respect to the base body of zirconium at least zirconium oxide prepared by using a supported catalyst in the carrier as a selection element of the first step Is a catalyst for purifying exhaust gas, wherein rhodium is further supported on a zirconium oxide-supported carrier having a content of 4% or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP35199695A JP3250714B2 (en) | 1994-12-28 | 1995-12-26 | Oxide-supported catalyst carrier, method for producing the same, and catalyst for purifying exhaust gas |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33957794 | 1994-12-28 | ||
| JP6-339577 | 1994-12-28 | ||
| JP35199695A JP3250714B2 (en) | 1994-12-28 | 1995-12-26 | Oxide-supported catalyst carrier, method for producing the same, and catalyst for purifying exhaust gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08229394A JPH08229394A (en) | 1996-09-10 |
| JP3250714B2 true JP3250714B2 (en) | 2002-01-28 |
Family
ID=26576456
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP35199695A Expired - Fee Related JP3250714B2 (en) | 1994-12-28 | 1995-12-26 | Oxide-supported catalyst carrier, method for producing the same, and catalyst for purifying exhaust gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3250714B2 (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3861385B2 (en) * | 1997-06-27 | 2006-12-20 | 株式会社豊田中央研究所 | Lean exhaust gas purification catalyst |
| JP3741303B2 (en) * | 1997-12-08 | 2006-02-01 | トヨタ自動車株式会社 | Exhaust gas purification catalyst |
| JP4045002B2 (en) * | 1998-02-02 | 2008-02-13 | 三井金属鉱業株式会社 | Composite oxide and exhaust gas purification catalyst using the same |
| JP4382180B2 (en) * | 1998-11-06 | 2009-12-09 | 株式会社キャタラー | Exhaust gas purification catalyst |
| US7307038B2 (en) * | 2002-10-21 | 2007-12-11 | W.R. Grace & Co. -Conn. | NOx reduction compositions for use in FCC processes |
| KR100638444B1 (en) * | 2004-10-18 | 2006-10-24 | 주식회사 엘지화학 | Hydrocarbon Cracking Catalyst using Chemical Liquid Deposition and Method for Preparing the Same |
| JP2009233580A (en) * | 2008-03-27 | 2009-10-15 | Mazda Motor Corp | Catalyst for cleaning exhaust gas and its manufacturing method |
| JP4674264B2 (en) * | 2009-07-31 | 2011-04-20 | 株式会社キャタラー | Exhaust gas purification catalyst |
| JP5734807B2 (en) * | 2011-10-21 | 2015-06-17 | 株式会社東芝 | Method for treating radioactive cesium and radioactive strontium-containing substances |
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1995
- 1995-12-26 JP JP35199695A patent/JP3250714B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08229394A (en) | 1996-09-10 |
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