CN114471578A - Preparation method of copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst and catalyst - Google Patents
Preparation method of copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst and catalyst Download PDFInfo
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- 239000003054 catalyst Substances 0.000 title claims abstract description 131
- 238000005984 hydrogenation reaction Methods 0.000 title claims abstract description 75
- -1 copper-zinc-aluminum Chemical compound 0.000 title claims abstract description 53
- 238000002360 preparation method Methods 0.000 title claims abstract description 35
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 title claims abstract 15
- 239000000463 material Substances 0.000 claims abstract description 139
- 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 claims abstract description 53
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 53
- 239000011734 sodium Substances 0.000 claims abstract description 53
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 claims abstract description 42
- 229910000431 copper oxide Inorganic materials 0.000 claims abstract description 42
- 229910052751 metal Inorganic materials 0.000 claims abstract description 42
- 239000002184 metal Substances 0.000 claims abstract description 42
- 239000005751 Copper oxide Substances 0.000 claims abstract description 41
- 239000012065 filter cake Substances 0.000 claims abstract description 39
- 238000002156 mixing Methods 0.000 claims abstract description 26
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims abstract description 25
- 238000003756 stirring Methods 0.000 claims abstract description 23
- 238000001035 drying Methods 0.000 claims abstract description 21
- 238000007873 sieving Methods 0.000 claims abstract description 21
- 238000005406 washing Methods 0.000 claims abstract description 21
- 238000001914 filtration Methods 0.000 claims abstract description 13
- 150000001879 copper Chemical class 0.000 claims abstract description 8
- 150000003751 zinc Chemical class 0.000 claims abstract description 7
- 230000032683 aging Effects 0.000 claims abstract description 3
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 88
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 74
- ONDPHDOFVYQSGI-UHFFFAOYSA-N zinc nitrate Chemical compound [Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ONDPHDOFVYQSGI-UHFFFAOYSA-N 0.000 claims description 70
- 239000011787 zinc oxide Substances 0.000 claims description 44
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 42
- 239000012808 vapor phase Substances 0.000 claims description 37
- XTVVROIMIGLXTD-UHFFFAOYSA-N copper(II) nitrate Chemical compound [Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O XTVVROIMIGLXTD-UHFFFAOYSA-N 0.000 claims description 34
- 238000000034 method Methods 0.000 claims description 30
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 29
- 239000012716 precipitator Substances 0.000 claims description 29
- 239000012071 phase Substances 0.000 claims description 28
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 21
- PTFCDOFLOPIGGS-UHFFFAOYSA-N Zinc dication Chemical compound [Zn+2] PTFCDOFLOPIGGS-UHFFFAOYSA-N 0.000 claims description 7
- 229910017773 Cu-Zn-Al Inorganic materials 0.000 claims description 6
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 claims description 5
- 229910001431 copper ion Inorganic materials 0.000 claims description 5
- ORTQZVOHEJQUHG-UHFFFAOYSA-L copper(II) chloride Chemical compound Cl[Cu]Cl ORTQZVOHEJQUHG-UHFFFAOYSA-L 0.000 claims description 4
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 2
- ZOIORXHNWRGPMV-UHFFFAOYSA-N acetic acid;zinc Chemical compound [Zn].CC(O)=O.CC(O)=O ZOIORXHNWRGPMV-UHFFFAOYSA-N 0.000 claims description 2
- 239000004202 carbamide Substances 0.000 claims description 2
- OPQARKPSCNTWTJ-UHFFFAOYSA-L copper(ii) acetate Chemical compound [Cu+2].CC([O-])=O.CC([O-])=O OPQARKPSCNTWTJ-UHFFFAOYSA-L 0.000 claims description 2
- 238000006386 neutralization reaction Methods 0.000 claims description 2
- 239000004246 zinc acetate Substances 0.000 claims description 2
- 238000001354 calcination Methods 0.000 claims 2
- 229910000611 Zinc aluminium Inorganic materials 0.000 abstract description 26
- HXFVOUUOTHJFPX-UHFFFAOYSA-N alumane;zinc Chemical compound [AlH3].[Zn] HXFVOUUOTHJFPX-UHFFFAOYSA-N 0.000 abstract description 26
- 238000006243 chemical reaction Methods 0.000 abstract description 24
- 239000011029 spinel Substances 0.000 abstract description 23
- 229910052596 spinel Inorganic materials 0.000 abstract description 23
- 230000003472 neutralizing effect Effects 0.000 abstract description 21
- 239000013078 crystal Substances 0.000 abstract description 9
- 238000007086 side reaction Methods 0.000 abstract description 8
- 239000000243 solution Substances 0.000 description 119
- 239000008367 deionised water Substances 0.000 description 68
- 229910021641 deionized water Inorganic materials 0.000 description 68
- 150000001299 aldehydes Chemical class 0.000 description 56
- 230000000052 comparative effect Effects 0.000 description 25
- 238000000967 suction filtration Methods 0.000 description 18
- 238000000975 co-precipitation Methods 0.000 description 16
- 229910052782 aluminium Inorganic materials 0.000 description 11
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 11
- 230000000694 effects Effects 0.000 description 9
- 239000011148 porous material Substances 0.000 description 9
- 239000006185 dispersion Substances 0.000 description 7
- 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 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 6
- 239000010949 copper Substances 0.000 description 6
- 238000001556 precipitation Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 229910052802 copper Inorganic materials 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 238000001878 scanning electron micrograph Methods 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- 230000018044 dehydration Effects 0.000 description 4
- 238000006297 dehydration reaction Methods 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 150000001298 alcohols Chemical class 0.000 description 3
- 239000012752 auxiliary agent Substances 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 3
- 238000001000 micrograph Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- KBPLFHHGFOOTCA-UHFFFAOYSA-N 1-Octanol Chemical compound CCCCCCCCO KBPLFHHGFOOTCA-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- 150000001340 alkali metals Chemical class 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- 150000001768 cations Chemical class 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- TVZPLCNGKSPOJA-UHFFFAOYSA-N copper zinc Chemical compound [Cu].[Zn] TVZPLCNGKSPOJA-UHFFFAOYSA-N 0.000 description 2
- PPQREHKVAOVYBT-UHFFFAOYSA-H dialuminum;tricarbonate Chemical compound [Al+3].[Al+3].[O-]C([O-])=O.[O-]C([O-])=O.[O-]C([O-])=O PPQREHKVAOVYBT-UHFFFAOYSA-H 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 239000002243 precursor Substances 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 239000011701 zinc Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 239000006004 Quartz sand Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 238000005882 aldol condensation reaction Methods 0.000 description 1
- 229940118662 aluminum carbonate Drugs 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 229910052792 caesium Inorganic materials 0.000 description 1
- TVFDJXOCXUVLDH-UHFFFAOYSA-N caesium atom Chemical compound [Cs] TVFDJXOCXUVLDH-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000012018 catalyst precursor Substances 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- VODBHXZOIQDDST-UHFFFAOYSA-N copper zinc oxygen(2-) Chemical compound [O--].[O--].[Cu++].[Zn++] VODBHXZOIQDDST-UHFFFAOYSA-N 0.000 description 1
- BERDEBHAJNAUOM-UHFFFAOYSA-N copper(I) oxide Inorganic materials [Cu]O[Cu] BERDEBHAJNAUOM-UHFFFAOYSA-N 0.000 description 1
- KRFJLUBVMFXRPN-UHFFFAOYSA-N cuprous oxide Chemical compound [O-2].[Cu+].[Cu+] KRFJLUBVMFXRPN-UHFFFAOYSA-N 0.000 description 1
- 229940112669 cuprous oxide Drugs 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 230000001376 precipitating effect Effects 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
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Classifications
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- B01J35/613—
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/005—Spinels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/80—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
-
- B01J35/40—
-
- B01J35/633—
-
- B01J35/635—
-
- B01J35/647—
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
- C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
- C07C29/14—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group
- C07C29/141—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group with hydrogen or hydrogen-containing gases
Abstract
The invention relates to the field of catalysts, and in particular relates to a preparation method of a copper-zinc-aluminum system gas-phase aldehyde hydrogenation catalyst and the catalyst, wherein the preparation method comprises the following steps: s1, preparing a mixed metal solution by using zinc salt and copper salt; s2, adding a precipitant solution containing an alkaline precipitant and sodium metaaluminate into the mixed metal solution prepared in the step S1, uniformly mixing, stirring the materials, preserving heat, neutralizing the materials, and aging; s3, washing and filtering the neutralized and aged material obtained in the step S2, and drying, roasting, tabletting, crushing and sieving a filter cake obtained by filtering to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst. In the invention, the aluminum oxide is completely combined in the zinc-aluminum spinel structure, the dispersibility of the copper oxide crystal grains is higher, the generation of side reactions can be reduced, and the selectivity and the conversion rate of the gas-phase aldehyde hydrogenation reaction are improved.
Description
Technical Field
The invention relates to the field of catalysts, and in particular relates to a preparation method of a copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst and the catalyst.
Background
Alcohols are important organic chemical raw materials, and a plurality of processes for producing the alcohols are available, and the process for preparing the alcohols by gas-phase aldehyde hydrogenation is mature at present. The reaction of aldehydes with hydrogen is generally carried out in the presence of a reducing metal compound as a hydrogenation catalyst. There are many industrial hydrogenation catalysts, and the middle liquid phase hydrogenation process widely uses nickel-based catalyst, while the gas phase hydrogenation process uses copper-based catalyst. At present, the most commonly used gas-phase aldehyde hydrogenation catalyst at home and abroad is a copper-zinc oxide system catalyst, and the widely adopted preparation method is a coprecipitation method, wherein a metal salt solution and a precipitator are added into a reaction kettle to be stirred, precipitated and aged, then dried and roasted to decompose a metal carbonate catalyst precursor into corresponding oxides, and then the corresponding oxides are reduced by hydrogen to obtain the catalyst taking metal copper and cuprous oxide as active components. The related prior art at home and abroad is optimized by adding an auxiliary agent or changing a precipitation mode on the basis, and alkali metals such as potassium, sodium, magnesium and the like or transition metals such as aluminum, manganese, molybdenum and the like are added to improve the dispersion degree of copper or modulate the acidity and alkalinity of a carrier, so that the activity, the selectivity and the stability are improved, but the properties of catalysts prepared by selecting different auxiliary agents and preparation methods are slightly different and have defects.
For example, Chinese patent "a preparation method of a copper-zinc-aluminum system gas phase aldehyde hydrogenation catalyst and a product thereof" (patent number: CN1883795A, published: 2006.12.27) discloses that a continuous stepwise coprecipitation method is used for preparing a gas phase aldehyde hydrogenation catalyst with a zinc-aluminum spinel structure, but the preparation method introduces zinc and aluminum in the form of nitrate, zinc and aluminum are both metal cations in the coprecipitation process and cannot directly react to form a precursor of the zinc-aluminum spinel structure, and the formed zinc-aluminum spinel structure is formed only by mechanically mixing and then roasting zinc-aluminum precipitates, so that most of aluminum exists independently in the catalyst in the form of aluminum oxide and is not combined into the zinc-aluminum spinel structure, so that the zinc-aluminum spinel structure is not obvious, the independently existing aluminum oxide has acidity and dehydration property, and various side reactions can be caused in the catalysis process to reduce selectivity; and the method of zinc-aluminum and copper fractional precipitation is adopted, the precipitates are only mechanically mixed in a reaction kettle, the nonuniformity in space and time exists, the dispersion degree of the roasted copper oxide in a zinc-aluminum spinel structure needs to be improved, and copper crystal grains are easy to aggregate and grow in the using process, so that the activity of the catalyst is reduced. In addition, as in some prior arts, the strength of the Cu-Zn-Al vapor phase aldehyde hydrogenation catalyst is improved by adding silica sol and alkali metal assistants such as sodium, strontium, cesium or zirconium in the coprecipitation preparation process or by adopting a secondary roasting process after precipitation.
However, the gas-phase hydrogenation of aldehyde to produce alcohol is a strongly exothermic reaction, and the above catalysts prepared in the prior art can cause more or less side reactions such as polymerization and condensation to occur during the hydrogenation of higher carbon number aldehyde at higher temperature, and generate high boiling point by-products; in addition, during use, copper crystallites aggregate to grow, resulting in a decrease in catalyst activity.
Disclosure of Invention
The present invention is directed to overcoming at least one of the above-mentioned drawbacks (disadvantages) of the prior art, and to provide a method for preparing a cu-zn-al vapor phase aldehyde hydrogenation catalyst and a catalyst thereof, in which alumina is completely incorporated into a zn-al spinel structure, and the dispersibility of the copper oxide crystal grains is higher, and the generation of side reactions can be reduced, and the selectivity and conversion rate of the vapor phase aldehyde hydrogenation reaction can be improved.
The technical scheme adopted by the invention is to provide a preparation method of a copper-zinc-aluminum system gas-phase aldehyde hydrogenation catalyst, which comprises the following steps:
s1, preparing a mixed metal solution by using zinc salt, copper salt and water;
s2, adding a precipitant solution containing an alkaline precipitant and sodium metaaluminate into the mixed metal solution prepared in the step S1, uniformly mixing, stirring the materials, and preserving heat to neutralize and age the materials;
s3, washing and filtering the neutralized and aged material obtained in the step S2, and drying, roasting, tabletting, crushing and sieving a filter cake obtained by filtering to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
In the technical scheme, zinc salt, copper salt and sodium metaaluminate are adopted as raw materials to carry out synchronous precipitation, copper ions, zinc ions and metaaluminate are uniformly mixed, the metaaluminate and the zinc ions are directly reacted to form a precursor of a zinc-aluminum spinel structure, the copper ions are uniformly dispersed in a reaction material system, the metaaluminate can be completely combined with the zinc ions to form the zinc-aluminum spinel structure after one-step precipitation roasting, and copper oxide is uniformly distributed in the zinc-aluminum spinel structure; compared with the catalyst prepared by firstly precipitating to prepare a zinc-aluminum spinel structure and then adding copper salt to disperse and precipitate, the one-step coprecipitation method can avoid low dispersion degree of copper oxide caused by the sequence of coprecipitation, in the catalyst prepared by the method, the copper oxide, the zinc oxide and the zinc-aluminum spinel structure have stronger interaction, the zinc-aluminum spinel structure has stronger dispersion and barrier effects on the copper oxide, so that the dispersion degree of copper oxide crystal grains is higher, and the zinc-aluminum spinel structure can avoid the aggregation and growth of the copper oxide crystal grains in the use process, thereby ensuring that the catalyst has high activity and high stability.
Further, in step S1, the concentration of the zinc ions in the mixed metal solution is 0.15-0.3 mol/L, and the concentration of the copper ions in the mixed metal solution is 0.1-0.2 mol/L.
Further, in step S2, the precipitant solution is a mixed precipitant solution prepared by mixing the alkaline precipitant and the sodium metaaluminate precipitant; the concentration of the alkaline precipitant in the mixed precipitant is 1-2 mol/L, and the concentration of the sodium metaaluminate is 0.03-0.5 mol/L.
Further, in step S2, the precipitant includes an alkaline precipitant solution and a sodium metaaluminate solution; the alkaline precipitator solution is prepared from an alkaline precipitator and water, and the concentration of the alkaline precipitator is 1-2 mol/L; the sodium metaaluminate solution is prepared from sodium metaaluminate and water, and the concentration of the sodium metaaluminate is 0.03-0.5 mol/L; the alkaline precipitant solution and the sodium metaaluminate solution are respectively added into the mixed metal solution; (ii) a The volume ratio (1-3) of the alkaline precipitant solution to the sodium metaaluminate solution is 1.
Further, the volume ratio of the mixed metal solution to the precipitant solution is (1-3): 1.
Further, the zinc salt is one or a mixture of zinc nitrate, copper acetate and copper chloride, and/or the copper salt is one or a mixture of copper nitrate, zinc acetate and copper chloride, and/or the alkaline precipitator is one or a mixture of sodium carbonate and urea.
Further, in step S2, the uniformly mixed materials are heated to 50-90 ℃ for heat preservation, and the materials are stirred at a rotating speed of 100-1000 rpm.
Further, in the step S2, the neutralization time is 15-30 min, the pH value of the neutralized material is 6.5-8.5, and/or the aging time is 25-35 min.
Further, in step S3, the roasting temperature is 360-400 ℃, and the roasting time is 4-5 hours.
The invention also provides a copper-zinc-aluminum system gas-phase aldehyde hydrogenation catalyst, which is prepared by the preparation method of the copper-zinc-aluminum system gas-phase aldehyde hydrogenation catalyst, and the catalyst comprises copper oxide, zinc oxide and aluminum oxide; the weight ratio of the copper oxide to the zinc oxide to the aluminum oxide is as follows: zinc oxide: alumina (30-40), alumina (55-65) and alumina (1-30).
In the technical scheme, the catalyst is prepared by adopting zinc salt, copper salt and sodium metaaluminate as raw materials through a one-step coprecipitation method, the diameter of copper oxide crystal grains in the catalyst is only 20-50 nm, the dispersity of the crystal grains is improved, aggregation is not easy to occur, and the specific surface area of the catalyst can reach 60-80 cm2·g-1The pore volume can reach 0.5-0.8 cm3·g-1The catalytic efficiency is improved; because the calcined alumina is completely combined in the zinc-aluminum spinel structure, the independent alumina does not exist in the catalyst, thereby weakening the acidity and the dehydration property of the catalyst and carrying out high-carbon-number aldehydeDuring the hydrogenation reaction, side reactions such as aldol condensation, aldehyde self-condensation and the like which occur at higher reaction temperature can be inhibited, so that the content of high-boiling-point byproducts can be reduced, and the selectivity and the conversion rate of the gas-phase aldehyde hydrogenation reaction are effectively improved.
Compared with the prior art, the invention has the beneficial effects that:
(1) sodium metaaluminate is used as an aluminum source, metaaluminate can prevent aluminum from forming free basic aluminum carbonate with a sodium carbonate precipitator as an independent cation to cause aggravation of side reaction, meanwhile, metaaluminate can be completely reacted with zinc ions to form a zinc-aluminum spinel structure, the zinc-aluminum spinel structure is more obvious and higher in strength, independent alumina is not used, the catalyst is better in heat resistance, acidity and dehydration are weakened, the side reaction is inhibited from proceeding, the content of byproducts is reduced, and the selectivity and the conversion rate of a main reaction are effectively improved;
(2) the preparation method of one-step coprecipitation is adopted, so that zinc ions, copper ions and metaaluminate radicals are precipitated synchronously, the interaction of copper oxide, zinc oxide and a zinc-aluminum spinel structure is enhanced after precipitation roasting, the zinc-aluminum spinel structure has a better barrier effect on the copper oxide, the dispersion degree of the copper oxide is improved, and copper oxide grains are not easy to aggregate, so that the catalyst is ensured to have high activity and high stability;
(3) the preparation method does not need to introduce other auxiliary agents, the coprecipitation reaction condition is simpler, the specific surface area and the pore volume of the prepared catalyst are larger, the catalytic efficiency is higher, and the aldehyde hydrogenation reaction is effectively promoted to be carried out;
(4) the preparation method reduces the use of nitrate and carbonate, reduces the emission of carbon dioxide in the preparation process, and is more environment-friendly.
Drawings
FIG. 1 is a scanning electron micrograph of a catalyst according to example 1 of the present invention.
FIG. 2 is a scanning electron micrograph of a catalyst according to example 2 of the present invention.
Fig. 3 is a scanning electron micrograph of the catalyst of comparative example 1 of the present invention.
Fig. 4 is a scanning electron micrograph of the catalyst of comparative example 2 of the present invention.
Fig. 5 is a scanning electron micrograph of the catalyst of comparative example 3 of the present invention.
Detailed Description
The drawings are only for purposes of illustration and are not to be construed as limiting the invention. For a better understanding of the following embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted. In the following examples, unless otherwise specified, all methods used are prior art and all materials used are commercially available products.
Example 1
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 a mixed metal solution was prepared using 11.34g of zinc nitrate, 5.47g of copper nitrate and 200ml of deionized water;
s2, preparing a mixed precipitator solution by using 13g of sodium carbonate, 0.23g of sodium metaaluminate and 71.5ml of deionized water; adding the mixed metal solution prepared in the step S1 and the prepared mixed precipitant solution into a three-neck flask in a concurrent flow manner, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
Example 2
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution by using 11.16g of zinc nitrate, 5.38g of copper nitrate and 200ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 0.46g of sodium metaaluminate and 71.5ml of deionized water; adding the mixed metal solution prepared in the step S1 and the prepared mixed precipitant solution into a three-neck flask in a concurrent flow manner, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 35.7:61: 3.3.
Example 3
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution using 9.88g of zinc nitrate, 4.74g of copper nitrate and 200ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 2.3g of sodium metaaluminate and 71.5ml of deionized water; adding the mixed metal solution prepared in the step S1 and the prepared mixed precipitant solution into a three-neck flask in a concurrent flow manner, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 31.5:54: 14.5.
Example 4
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution using 10.97g of zinc nitrate, 5.77g of copper nitrate and 200ml of deionized water;
s2, preparing an alkaline precipitator solution by using 13g of sodium carbonate and 65ml of deionized water, and preparing a sodium metaaluminate solution by using 0.23g of sodium metaaluminate and 6.5ml of deionized water; sequentially adding the mixed metal solution prepared in the step S1, the prepared alkaline precipitator solution and the sodium metaaluminate solution into a three-neck flask in parallel, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min; s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight proportion of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 38.3:60: 1.7.
Example 5
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution by using 11.9g of zinc nitrate, 5.0g of copper nitrate and 200ml of deionized water;
s2, preparing an alkaline precipitator solution by using 13g of sodium carbonate and 65ml of deionized water, and preparing a sodium metaaluminate solution by using 0.46g of sodium metaaluminate and 6.5ml of deionized water; sequentially adding the mixed metal solution prepared in the step S1, the prepared alkaline precipitator solution and the sodium metaaluminate solution into a three-neck flask in parallel, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 32.7:64: 3.3.
Example 6
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution by using 10.06g of zinc nitrate, 4.6g of copper nitrate and 200ml of deionized water;
s2, preparing an alkaline precipitator solution by using 13g of sodium carbonate and 65ml of deionized water, and preparing a sodium metaaluminate solution by using 2.3g of sodium metaaluminate and 6.5ml of deionized water; sequentially adding the mixed metal solution prepared in the step S1, the prepared alkaline precipitator solution and the sodium metaaluminate solution into a three-neck flask in parallel, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 30.5:54: 14.5.
Example 7
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 a mixed metal solution was prepared using 11.34g of zinc nitrate, 5.47g of copper nitrate and 200ml of deionized water;
s2, preparing an alkaline precipitator solution by using 13g of sodium carbonate and 65ml of deionized water, and preparing a sodium metaaluminate solution by using 0.23g of sodium metaaluminate and 6.5ml of deionized water; sequentially adding the mixed metal solution prepared in the step S1, the prepared sodium metaaluminate solution and the prepared alkaline precipitator solution into a three-neck flask in parallel, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
Example 8
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution using 11.16g of zinc nitrate, 5.38g of copper nitrate and 200ml of deionized water;
s2, preparing an alkaline precipitator solution by using 13g of sodium carbonate and 65ml of deionized water, and preparing a sodium metaaluminate solution by using 0.46g of sodium metaaluminate and 6.5ml of deionized water; sequentially adding the mixed metal solution prepared in the step S1, the prepared sodium metaaluminate solution and the prepared alkaline precipitator solution into a three-neck flask in parallel, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min; (ii) a
S3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 35.7:61: 3.3.
Example 9
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1 preparing a mixed metal solution by using 10.06g of zinc nitrate, 4.6g of copper nitrate and 200ml of deionized water;
s2, preparing an alkaline precipitator solution by using 13g of sodium carbonate and 65ml of deionized water, and preparing a sodium metaaluminate solution by using 2.3g of sodium metaaluminate and 6.5ml of deionized water; sequentially adding the mixed metal solution prepared in the step S1, the prepared sodium metaaluminate solution and the prepared alkaline precipitator solution into a three-neck flask in parallel, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, performing suction filtration, drying a filter cake obtained through filtration, roasting the filter cake at 360-400 ℃ for 4-5 hours, tabletting, crushing, and sieving with a 20-40-mesh sieve to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 31.5:54: 14.5.
Example 10
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 11.34g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 5.47g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 0.23g of sodium metaaluminate and 71.5ml of deionized water; sequentially adding the zinc nitrate solution, the copper nitrate solution and the mixed precipitator solution prepared in the step S1 into a three-neck flask in a parallel flow mode, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
Example 11
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 11.16g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 5.38g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 0.46g of sodium metaaluminate and 71.5ml of deionized water; sequentially adding the zinc nitrate solution, the copper nitrate solution and the mixed precipitator solution prepared in the step S1 into a three-neck flask in a parallel flow mode, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 35.7:61: 3.3.
Example 12
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 10.06g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 4.6g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 2.3g of sodium metaaluminate and 71.5ml of deionized water; sequentially adding the zinc nitrate solution, the copper nitrate solution and the mixed precipitator solution prepared in the step S1 into a three-neck flask in a parallel flow mode, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 31.5:54:14.5
Example 13
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 11.34g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 5.47g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 0.23g of sodium metaaluminate and 71.5ml of deionized water; sequentially adding the copper nitrate solution, the zinc nitrate solution and the mixed precipitator solution prepared in the step S1 into a three-neck flask in a parallel flow mode, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
Example 14
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 11.16g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 5.38g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 0.46g of sodium metaaluminate and 71.5ml of deionized water; sequentially adding the copper nitrate solution, the zinc nitrate solution and the mixed precipitator solution prepared in the step S1 into a three-neck flask in a parallel flow mode, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 35.7:61: 3.3.
Example 15
The embodiment provides a copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 10.06g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 4.6g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 2.3g of sodium metaaluminate and 71.5ml of deionized water; sequentially adding the copper nitrate solution, the zinc nitrate solution and the mixed precipitator solution prepared in the step S1 into a three-neck flask in a parallel flow mode, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 31.5:54: 14.5.
Comparative example 1
This comparative example provides a copper zinc aluminum based vapor phase aldehyde hydrogenation catalyst, which is essentially the same as example 1 except that it uses a stepwise coprecipitation method and aluminum nitrate as an aluminum source, and the preparation method comprises the steps of:
s1 preparing a zinc-copper mixed metal solution by using 10.6g of zinc nitrate, 5.47g of copper nitrate and 200ml of deionized water; preparing a zinc-aluminum mixed metal solution by using 0.74g of aluminum nitrate, 0.74g of zinc nitrate and 20ml of deionized water; preparing an alkaline precipitant solution by using 13.3g of sodium carbonate and 71.5ml of deionized water;
s2, adding the zinc-aluminum mixed metal solution prepared in the step S1 and the basic precipitant solution into a three-neck flask in a concurrent flow manner, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, adding the zinc-copper mixed metal solution into the neutralized and aged material obtained in the step S2, uniformly mixing the material, keeping the temperature of the material at 80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the material within 15-25 min, controlling the pH of the material at 7.0-8.0, and then keeping the material aged for 25-35 min;
s4, washing the neutralized and aged material obtained in the step S3 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
Comparative example 2
This comparative example provides a copper-zinc-aluminum system vapor phase aldehyde hydrogenation catalyst, which is essentially the same as example 1 except that it uses a stepwise coprecipitation method, and the preparation method comprises the following steps:
s1, preparing a zinc nitrate solution by using 11.34g of zinc nitrate and 100ml of deionized water, and preparing a copper nitrate solution by using 5.47g of copper nitrate and 100ml of deionized water;
s2 preparing a mixed precipitant solution from 13g of sodium carbonate, 0.23g of sodium metaaluminate and 71.5ml of deionized water; adding the zinc nitrate solution prepared in the step S1 and the mixed precipitator solution into a three-neck flask in a concurrent flow manner, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, adding the copper nitrate solution prepared in the step S1 into the neutralized and aged material in the step S2, uniformly mixing the materials, keeping the temperature of the materials at 80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and then keeping the materials aged for 25-35 min;
s4, washing the neutralized and aged material obtained in the step S3 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
Comparative example 3
This comparative example provides a copper-zinc-aluminum based vapor phase aldehyde hydrogenation catalyst, which is substantially the same as example 1 except that aluminum nitrate was used as the aluminum source, and which was prepared by a method comprising the steps of:
S1A mixed metal solution was prepared using 11.34g of zinc nitrate, 5.47g of copper nitrate, 0.75g of aluminum nitrate and 200ml of deionized water;
s2 preparing an alkaline precipitant solution using 13g of sodium carbonate and 71.5ml of deionized water; adding the mixed metal solution prepared in the step S1 and the prepared basic precipitant solution into a three-neck flask in a concurrent flow manner, uniformly mixing the materials, keeping the temperature of the materials at 70-80 ℃, stirring at the rotating speed of 150-300 rpm, titrating and neutralizing the materials within 15-25 min, controlling the pH of the materials at 7.0-8.0, and keeping the materials aged for 25-35 min;
s3, washing the neutralized and aged material obtained in the step S2 with deionized water for a plurality of times, carrying out suction filtration, drying the filtered filter cake, roasting the filter cake at 360-400 ℃ for 4-5 h, tabletting, crushing, and sieving with a 20-40 mesh sieve to obtain the copper-zinc-aluminum vapor phase aldehyde hydrogenation catalyst.
The weight ratio of copper oxide, zinc oxide and aluminum oxide in the prepared catalyst is as follows: zinc oxide: alumina 36.3:62: 1.7.
The catalysts prepared in examples 1 and 2 and comparative examples 1 to 3 were subjected to physical property tests, and the results of the measured physical property indexes are shown in table 1.
Table 1:
| sample (I) | SBET a(m2.g-1) | V(cm3.g-1) | Pore width(nm) | Crystal grain diameter (nm) of |
| Sample | ||||
| 1 | 76.7 | 0.75 | 41.68 | 35 |
| Sample 2 | 71.8 | 0.59 | 35.75 | 24 |
| Comparative example 1 | 61.2 | 0.44 | 29.05 | 78 |
| Comparative example 2 | 69.3 | 0.57 | 31.74 | 82 |
| Comparative example 3 | 68.7 | 0.46 | 34.28 | 86 |
As can be seen from table 1, in examples 1 and 2 using the one-step co-precipitation method, compared with comparative examples 1 and 2 using the fractional co-precipitation method, the prepared catalysts have larger specific surface area, pore volume and pore diameter, and smaller grain diameter of copper oxide, which proves that the catalyst has higher dispersity and thus higher catalytic activity; comparative example 3 also adopts a one-step coprecipitation method, and the specific surface area, pore volume and pore diameter of the catalyst are correspondingly improved compared with those of comparative example 1 adopting a distributed coprecipitation method, but the specific surface area, pore volume and pore diameter of the catalyst of comparative example 3 are smaller and the grain diameter of copper oxide is larger than those of example 1, which indicates that the dispersity is lower and the activity of the catalyst is weaker because the zinc-aluminum spinel structure is not obvious because aluminum nitrate is used as an aluminum source.
The catalysts prepared in examples 1 and 2 and comparative examples 1 to 3 were observed under a scanning electron microscope. Fig. 1 and 2 are scanning electron microscope images of the catalysts of examples 1 and 2, respectively, as shown in the figures, the zinc aluminum spinel structure of fig. 1 and 2 is clear, and the copper oxide grains are smaller and uniformly dispersed; fig. 3 and 5 are scanning electron microscope images of the catalysts of comparative examples 1 and 3, respectively, as shown in the figures, since the catalysts of comparative examples 1 and 3 use aluminum nitrate as an aluminum source, the zinc-aluminum spinel structure is not obvious, and the copper oxide crystal grains are larger; fig. 4 is a scanning electron microscope image of the catalyst of comparative example 2, and as shown in the figure, although sodium metaaluminate is used as an aluminum source, a fractional coprecipitation method is used, and the grain size of copper oxide is large and the dispersion degree is poor.
The catalysts prepared in examples 1 and 2 and comparative examples 1 to 3 were subjected to a performance test, and a gas phase aldehyde hydrogenation reaction was carried out using a 200ml fixed bed gas phase hydrogenation apparatus to evaluate that the starting material was industrial octenal. The specific test method comprises the following steps:
s1, filling catalyst particles into the middle of the reaction tube, and filling quartz sand into the two ends of the reaction tube;
s2, introducing a hydrogen reduction catalyst, wherein in the reduction process, the hydrogen flow is 300ml/min, the reduction temperature is 240 ℃, and the reduction time is 6 h;
s3, after the reduction is finished, introducing nitrogen to reduce the temperature to 160 ℃, introducing reaction materials to start reaction, and analyzing the obtained product by gas chromatography, wherein the analysis result is shown in Table 2; in the reaction process, the hydrogen-aldehyde ratio of the reaction materials is 8000:1, and the reaction space velocity is 0.35h-1The reaction pressure was 0.45 MPa.
Table 2:
| item | Example 1 | Example 2 | Comparative example 1 | Comparative example 2 | Comparative example 3 |
| Percent conversion of octyl vinyl aldehyde, wt% | 99.98 | 99.74 | 99.23 | 98.32 | 99.12 |
| Octanol selectivity,% | 99.64 | 99.43 | 98.72 | 99.35 | 98.17 |
As can be seen from Table 2, the conversion and selectivity of the reaction are higher due to the higher activity of the catalysts of examples 1 and 2, especially the conversion rate can reach nearly 100%, because the catalysts of examples 1 and 2 have no alumina which exists alone, the acidity and the dehydration performance of the catalysts are greatly weakened, and the side reaction can be effectively inhibited.
It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the technical solutions of the present invention, and are not intended to limit the specific embodiments of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention claims should be included in the protection scope of the present invention claims.
Claims (10)
1. A preparation method of a copper-zinc-aluminum system gas-phase aldehyde hydrogenation catalyst is characterized by comprising the following steps:
s1, preparing a mixed metal solution by using zinc salt, copper salt and water;
s2, adding a precipitant solution containing an alkaline precipitant and sodium metaaluminate into the mixed metal solution prepared in the step S1, uniformly mixing, stirring the materials, and preserving heat to neutralize and age the materials;
s3, washing and filtering the neutralized and aged material obtained in the step S2, and drying, roasting, tabletting, crushing and sieving a filter cake obtained by filtering to obtain the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst.
2. The method of claim 1, wherein in step S1, the concentration of zinc ions in the mixed metal solution is 0.15-0.3 mol/L, and the concentration of copper ions in the mixed metal solution is 0.1-0.2 mol/L.
3. The method for preparing a copper-zinc-aluminum based vapor phase aldehyde hydrogenation catalyst according to claim 1, wherein in step S2, the precipitant solution is a mixed precipitant solution prepared by mixing the alkaline precipitant and the sodium metaaluminate precipitant; the concentration of the alkaline precipitant in the mixed precipitant is 1-2 mol/L, and the concentration of the sodium metaaluminate is 0.03-0.5 mol/L.
4. The method for preparing a Cu-Zn-Al based vapor phase aldehyde hydrogenation catalyst according to claim 1, wherein in step S2, the precipitant comprises an alkaline precipitant solution and a sodium metaaluminate solution; the alkaline precipitator solution is prepared from an alkaline precipitator and water, and the concentration of the alkaline precipitator is 1-2 mol/L; the sodium metaaluminate solution is prepared from sodium metaaluminate and water, and the concentration of the sodium metaaluminate is 0.03-0.5 mol/L; the alkaline precipitant solution and the sodium metaaluminate solution are respectively added into the mixed metal solution; (ii) a The volume ratio (1-3) of the alkaline precipitant solution to the sodium metaaluminate solution is 1.
5. The method for preparing a Cu-Zn-Al vapor phase aldehyde hydrogenation catalyst according to claim 1, wherein the volume ratio of the mixed metal solution to the precipitant solution is (1-3): 1.
6. The method for preparing the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst according to any one of claims 1 to 4, wherein the zinc salt is one or more of zinc nitrate, copper acetate and copper chloride, and/or the copper salt is one or more of copper nitrate, zinc acetate and copper chloride, and/or the alkaline precipitant is one or two of sodium carbonate and urea.
7. The method for preparing a Cu-Zn-Al vapor phase aldehyde hydrogenation catalyst according to claim 1, wherein in step S2, the uniformly mixed materials are heated to 50-90 ℃ and kept warm, and the materials are stirred at a rotation speed of 100-1000 rpm.
8. The method for preparing the Cu-Zn-Al vapor phase aldehyde hydrogenation catalyst according to claim 1, wherein in step S2, the neutralization time is 15-30 min, the pH value of the neutralized material is 6.5-8.5, and/or the aging time is 25-35 min.
9. The method for preparing a Cu-Zn-Al vapor phase aldehyde hydrogenation catalyst according to claim 1, wherein in step S3, the calcination temperature is 360-400 ℃ and the calcination time is 4-5 h.
10. A copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst, which is prepared by the preparation method of the copper-zinc-aluminum gas-phase aldehyde hydrogenation catalyst according to any one of claims 1 to 8, and comprises copper oxide, zinc oxide and aluminum oxide; the weight ratio of the copper oxide to the zinc oxide to the aluminum oxide is as follows: zinc oxide: alumina (30-40), alumina (55-65) and alumina (1-30).
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| US5155086A (en) * | 1989-09-12 | 1992-10-13 | Engelhard Corporation | Hydrogenation catalyst, process for preparing and process of using said catalyst |
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| CN107774262A (en) * | 2016-08-31 | 2018-03-09 | 中国石油化工股份有限公司 | The preparation method of copper zinc catalyst |
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| CN105107512A (en) * | 2015-09-10 | 2015-12-02 | 西南化工研究设计院有限公司 | Method for preparing copper-based butyraldehyde hydrogenation butanol catalyzer through coprecipitation and spray-drying |
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