CN110586144A - Film catalyst precursor, film catalyst, preparation method and application thereof - Google Patents
Film catalyst precursor, film catalyst, preparation method and application thereof Download PDFInfo
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- CN110586144A CN110586144A CN201910803269.6A CN201910803269A CN110586144A CN 110586144 A CN110586144 A CN 110586144A CN 201910803269 A CN201910803269 A CN 201910803269A CN 110586144 A CN110586144 A CN 110586144A
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- palladium
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- oxide
- catalyst
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- 239000003054 catalyst Substances 0.000 title claims abstract description 118
- 239000012018 catalyst precursor Substances 0.000 title claims abstract description 41
- 238000002360 preparation method Methods 0.000 title claims abstract description 41
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims abstract description 309
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 113
- 229910052751 metal Inorganic materials 0.000 claims abstract description 112
- 239000002184 metal Substances 0.000 claims abstract description 112
- 239000002131 composite material Substances 0.000 claims abstract description 107
- 239000012528 membrane Substances 0.000 claims abstract description 95
- KLZUFWVZNOTSEM-UHFFFAOYSA-K Aluminum fluoride Inorganic materials F[Al](F)F KLZUFWVZNOTSEM-UHFFFAOYSA-K 0.000 claims abstract description 89
- 239000000919 ceramic Substances 0.000 claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 36
- 238000001035 drying Methods 0.000 claims abstract description 30
- IRPGOXJVTQTAAN-UHFFFAOYSA-N 2,2,3,3,3-pentafluoropropanal Chemical compound FC(F)(F)C(F)(F)C=O IRPGOXJVTQTAAN-UHFFFAOYSA-N 0.000 claims abstract description 26
- 239000002243 precursor Substances 0.000 claims abstract description 25
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 24
- 238000006243 chemical reaction Methods 0.000 claims abstract description 22
- 239000000654 additive Substances 0.000 claims abstract description 19
- 238000007598 dipping method Methods 0.000 claims abstract description 18
- 239000002253 acid Substances 0.000 claims abstract description 17
- 238000010992 reflux Methods 0.000 claims abstract description 16
- 239000004094 surface-active agent Substances 0.000 claims abstract description 16
- 230000000996 additive effect Effects 0.000 claims abstract description 15
- -1 aluminum alkoxide Chemical class 0.000 claims abstract description 13
- 150000003839 salts Chemical class 0.000 claims abstract description 12
- 239000002904 solvent Substances 0.000 claims abstract description 11
- 239000012046 mixed solvent Substances 0.000 claims abstract description 8
- 239000003495 polar organic solvent Substances 0.000 claims abstract description 7
- 238000011068 loading method Methods 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 23
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical group [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims description 20
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 19
- 238000002791 soaking Methods 0.000 claims description 17
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 14
- SMZOGRDCAXLAAR-UHFFFAOYSA-N aluminium isopropoxide Chemical group [Al+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] SMZOGRDCAXLAAR-UHFFFAOYSA-N 0.000 claims description 14
- 229910017604 nitric acid Inorganic materials 0.000 claims description 14
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical group CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 13
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 13
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 13
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 12
- 238000005406 washing Methods 0.000 claims description 12
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 10
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 9
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 7
- 229910000040 hydrogen fluoride Inorganic materials 0.000 claims description 7
- 239000011135 tin Substances 0.000 claims description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 6
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 claims description 6
- 229910000423 chromium oxide Inorganic materials 0.000 claims description 6
- 239000001257 hydrogen Substances 0.000 claims description 6
- 229910000480 nickel oxide Inorganic materials 0.000 claims description 6
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims description 6
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 6
- 229910001887 tin oxide Inorganic materials 0.000 claims description 6
- 239000011787 zinc oxide Substances 0.000 claims description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 5
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 5
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 5
- 229910052804 chromium Inorganic materials 0.000 claims description 5
- 239000011651 chromium Substances 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 5
- 238000000576 coating method Methods 0.000 claims description 5
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 229910052718 tin Inorganic materials 0.000 claims description 5
- 229910052725 zinc Inorganic materials 0.000 claims description 5
- 239000011701 zinc Substances 0.000 claims description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 4
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 4
- 229910002651 NO3 Inorganic materials 0.000 claims description 4
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 4
- 239000000460 chlorine Substances 0.000 claims description 4
- 229910052801 chlorine Inorganic materials 0.000 claims description 4
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 229910003445 palladium oxide Inorganic materials 0.000 claims description 4
- JQPTYAILLJKUCY-UHFFFAOYSA-N palladium(ii) oxide Chemical compound [O-2].[Pd+2] JQPTYAILLJKUCY-UHFFFAOYSA-N 0.000 claims description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 3
- 230000007935 neutral effect Effects 0.000 claims description 3
- WOZZOSDBXABUFO-UHFFFAOYSA-N tri(butan-2-yloxy)alumane Chemical compound [Al+3].CCC(C)[O-].CCC(C)[O-].CCC(C)[O-] WOZZOSDBXABUFO-UHFFFAOYSA-N 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims 1
- 239000012752 auxiliary agent Substances 0.000 abstract description 8
- 230000003197 catalytic effect Effects 0.000 abstract description 8
- 238000005245 sintering Methods 0.000 abstract description 4
- 229910021645 metal ion Inorganic materials 0.000 abstract description 3
- 239000000758 substrate Substances 0.000 abstract description 3
- 238000009616 inductively coupled plasma Methods 0.000 description 22
- 230000000052 comparative effect Effects 0.000 description 17
- 238000003756 stirring Methods 0.000 description 14
- 239000012298 atmosphere Substances 0.000 description 13
- 238000001291 vacuum drying Methods 0.000 description 11
- 230000008569 process Effects 0.000 description 10
- QSWDMMVNRMROPK-UHFFFAOYSA-K chromium(3+) trichloride Chemical compound [Cl-].[Cl-].[Cl-].[Cr+3] QSWDMMVNRMROPK-UHFFFAOYSA-K 0.000 description 7
- RFCAUADVODFSLZ-UHFFFAOYSA-N 1-Chloro-1,1,2,2,2-pentafluoroethane Chemical compound FC(F)(F)C(F)(F)Cl RFCAUADVODFSLZ-UHFFFAOYSA-N 0.000 description 6
- 229910021556 Chromium(III) chloride Inorganic materials 0.000 description 6
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 6
- 239000011636 chromium(III) chloride Substances 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 description 6
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 5
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 description 5
- 238000009835 boiling Methods 0.000 description 5
- 235000019406 chloropentafluoroethane Nutrition 0.000 description 5
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 5
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 5
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 5
- 239000007789 gas Substances 0.000 description 4
- 238000000746 purification Methods 0.000 description 4
- 239000011592 zinc chloride Substances 0.000 description 4
- 239000003463 adsorbent Substances 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- GTLACDSXYULKMZ-UHFFFAOYSA-N pentafluoroethane Chemical compound FC(F)C(F)(F)F GTLACDSXYULKMZ-UHFFFAOYSA-N 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000002585 base Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000001354 calcination Methods 0.000 description 2
- 239000012043 crude product Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229910021555 Chromium Chloride Inorganic materials 0.000 description 1
- 229910009523 YCl3 Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 239000012684 catalyst carrier precursor Substances 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000008280 chlorinated hydrocarbons Chemical class 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 238000006298 dechlorination reaction Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000000645 desinfectant Substances 0.000 description 1
- 238000010586 diagram 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
- 239000012153 distilled water Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 238000004508 fractional distillation Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000005984 hydrogenation reaction Methods 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000003380 propellant Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- PCMOZDDGXKIOLL-UHFFFAOYSA-K yttrium chloride Chemical compound [Cl-].[Cl-].[Cl-].[Y+3] PCMOZDDGXKIOLL-UHFFFAOYSA-K 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
Classifications
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- 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
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/06—Halogens; Compounds thereof
- B01J27/128—Halogens; Compounds thereof with iron group metals or platinum group metals
- B01J27/13—Platinum group metals
-
- 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
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/06—Halogens; Compounds thereof
- B01J27/132—Halogens; Compounds thereof with chromium, molybdenum, tungsten or polonium
-
- 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
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/06—Halogens; Compounds thereof
- B01J27/135—Halogens; Compounds thereof with titanium, zirconium, hafnium, germanium, tin or lead
-
- 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
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/06—Halogens; Compounds thereof
- B01J27/138—Halogens; Compounds thereof with alkaline earth metals, magnesium, beryllium, zinc, cadmium or mercury
-
- 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
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/20—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state
- B01J35/23—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state in a colloidal state
-
- 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
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
- B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
-
- 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
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/61—Surface area
- B01J35/615—100-500 m2/g
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0201—Impregnation
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/06—Washing
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
- B01J37/10—Heat treatment in the presence of water, e.g. steam
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/16—Reducing
- B01J37/18—Reducing with gases containing free hydrogen
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
- C07C17/20—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C19/00—Acyclic saturated compounds containing halogen atoms
- C07C19/08—Acyclic saturated compounds containing halogen atoms containing fluorine
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- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
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- Thermal Sciences (AREA)
- Catalysts (AREA)
Abstract
The invention relates to the technical field of catalysts, in particular to a membrane catalyst precursor, a membrane catalyst, and preparation methods and applications thereof. The preparation method of the precursor comprises the following steps: slowly dripping an acid solvent into the polar organic solvent to obtain a mixed solvent; respectively adding aluminum alkoxide, metal additive salt, chloropalladate solution and surfactant into the mixed solvent, and refluxing in a constant-temperature water bath to obtain palladium-containing composite sol; and (3) placing the porous ceramic into the palladium-containing composite sol for dipping, drying and roasting. According to the membrane catalyst and the preparation method thereof, the palladium-containing composite aluminum fluoride membrane layer with larger specific surface area is prepared, so that the catalytic activity of the catalyst is improved; by adding the surfactant, metal ions on the surface of the catalyst are dispersed more uniformly, and active metal palladium sintering is reduced; the metal auxiliary agent is added to improve the surface acidity and alkalinity of the membrane catalyst, so that a reaction substrate is easier to enrich on the surface of the membrane catalyst, and the conversion efficiency of the membrane catalyst is improved.
Description
Technical Field
The invention relates to the technical field of catalysts, in particular to a membrane catalyst precursor, a membrane catalyst, and preparation methods and applications thereof.
Background
R125 is also called pentafluoroethane, is a chlorine-free Freon substitute, can be used as a refrigerant, a foaming agent, a fire extinguishing agent, a propellant, a carrier gas of a disinfectant and the like, and the application requires that the R125 does not contain other chlorinated hydrocarbon impurities and has higher purity. However, in the current several production methods, the crude product can not meet the requirements, and besides R115, the crude product also contains byproducts such as R113, R114, R115, R123 and the like to different degrees according to different synthesis methods. These by-products, with the exception of R115, can be separated from R125 by conventional fractional distillation techniques, however, R115, because of its relatively close boiling points (R115 has a boiling point of-38.7 ℃ C. and R125 has a boiling point of-48.5 ℃ C.), and an azeotrope exists at 21% by weight of R125 in R115, which has a boiling point of-48.5 ℃ at 1 atm, which is very close to the boiling point of-48.1 ℃ C. of R125, adding considerable difficulty to the production of high purity R125.
The R115 separation method in R125 mainly reduces the content of R115 in the R125 product in the reaction stage, the purification stage and the rectification stage. By using a specific catalyst and specific reaction conditions, the production of R115 is reduced in the reaction stage, but excessively reducing the content of R115 results in a decrease in the yield of R125.
A purification stage: mainly converting R115 in R125 into R125 and R116, or adsorbing R115 by using an adsorbent to remove R115. The conversion of R115 into R116 easily causes the decomposition of R125 at a too high temperature and other impurities are obtained, so that the method has severe requirements on reaction conditions, is high in cost and can cause the loss of pentafluoroethane due to the reaction. The catalyst used for converting R115 into R125 is high in requirement, volatile and active, and needs a large amount of hydrogen, so that the enterprise cost is increased. The adsorbent method requires that R115 is periodically desorbed from the adsorbent, requires a plurality of units for continuous operation, and is complicated in production process.
A rectification stage: and removing R115 by adopting an unconventional extraction rectification method to obtain a high-purity R125 product. The process requires the use of specific extractants and has limitations for extremely low levels of R115.
The existing method for producing high-purity R125 mainly adopts a specific catalyst to reduce the content of R115 in a reaction stage, if the content of R115 is too high, a post-treatment system needs to be correspondingly adjusted, and the adjustment and the modification of the post-treatment system inevitably cause the increase of the production cost.
In view of the above, it is a technical problem to be solved in the art to provide a new membrane catalyst capable of providing trace amount of R115 conversion.
Disclosure of Invention
The present invention aims to overcome the above defects of the prior art and provide a membrane catalyst precursor, a membrane catalyst, and preparation methods and applications thereof.
The object of the invention can be achieved by the following technical measures:
the invention provides a Pd/AlF3A film catalyst precursor, the catalyst precursor comprising: the composite coating comprises a porous ceramic layer and a porous composite layer laminated on the surface of the porous ceramic layer, wherein the porous composite layer comprises aluminum oxide, metal auxiliary oxide and palladium oxide, and the metal auxiliary oxide comprises at least two of zinc oxide, chromium oxide, nickel oxide or tin oxide.
Preferably, the mass ratio of the aluminum in the aluminum oxide to each metal promoter in the metal promoter oxide is 100: (0.5 to 3);
and/or the thickness of the porous composite layer is 440-560 μm.
The invention also provides Pd/AlF3A method of preparing a precursor for a film catalyst, the method comprising:
slowly dripping an acid solvent into the polar organic solvent under the condition that the pH value is 6.5-7.5 to obtain a mixed solvent;
respectively adding aluminum alkoxide, metal additive salt, chloropalladate solution and surfactant into the mixed solvent, and refluxing in a constant-temperature water bath at 50-70 ℃ to obtain palladium-containing composite sol;
placing the porous ceramic in the palladium-containing composite sol for dipping, drying and roasting to obtain Pd/AlF3A film catalyst precursor;
wherein the metal additive salt comprises at least two of chloride or nitrate of zinc, chromium, nickel and tin.
Preferably, the mass ratio of the aluminum in the aluminum alkoxide to each metal promoter in the metal promoter salt is 100: (0.5 to 3);
and/or the ratio of the molar amount of the metallic palladium in the chloropalladate to the molar amount of the surfactant is 1: (50-80);
and/or, the polar organic solvent is absolute ethyl alcohol;
and/or the acid solvent is one of hydrochloric acid, nitric acid or acetic acid, and the mass percentage of the acid solvent is 36-70%;
and/or the aluminum alkoxide is aluminum isopropoxide or aluminum butoxide;
and/or the surfactant is cetyl trimethyl ammonium bromide;
and/or the refluxing time of the constant-temperature water bath is 10-15 hours;
and/or, the steps of immersing, drying and roasting the porous ceramic in the palladium-containing composite sol are repeated for a plurality of times;
and/or the dipping temperature is 50-60 ℃, and the dipping time is 10-15 hours;
and/or the roasting temperature is 300-550 ℃.
The invention also provides Pd/AlF3The membrane catalyst comprises a porous ceramic layer, a porous palladium-containing composite alumina layer stacked on the surface of the porous ceramic layer and a porous palladium-containing composite aluminum fluoride layer stacked on the surface of the porous palladium-containing composite alumina layer, wherein the porous palladium-containing composite alumina layer comprises alumina, a metal assistant oxide and metal palladium, the porous palladium-containing composite aluminum fluoride layer comprises aluminum fluoride, a metal assistant oxide and metal palladium, and the metal assistant oxide in the porous palladium-containing composite alumina layer or the porous palladium-containing composite aluminum fluoride layer comprises at least two of zinc oxide, chromium oxide, nickel oxide or tin oxide.
Preferably, the Pd/AlF3The surface area of the membrane catalyst is 180-220 m2/g;
Or the thickness of the porous palladium-containing composite aluminum oxide layer is 220-280 μm, and the thickness of the porous palladium-containing composite aluminum fluoride layer is 220-280 μm;
or, the Pd/AlF3The palladium loading capacity of the membrane catalyst is 1-5%;
or in the porous palladium-containing composite aluminum oxide layer, the mass ratio of the aluminum in the aluminum oxide to the metal additives in the metal additive oxide is 100: (0.5 to 3); in the porous palladium-containing composite aluminum fluoride layer, the ratio of the mass of aluminum in the aluminum fluoride to the mass of metal in the metal auxiliary oxide is 100: (0.5 to 3).
The invention also provides Pd/AlF3A method for preparing a membrane catalyst, the method comprising:
Pd/AlF3Placing the precursor of the membrane catalyst in a hydrogen fluoride solution, soaking for 0.5-2 hours in a water bath at 50-70 ℃, and then carrying out Pd/AlF3Washing the film catalyst precursor to be neutral and drying;
introducing hydrogen at 380-400 ℃ to react the Pd/AlF3Reduction of film catalyst precursor to obtain Pd/AlF3A membrane catalyst;
wherein, the Pd/AlF3The precursor of the film catalyst is the Pd/AlF3Film catalyst precursor or Pd/AlF prepared according to the precursor preparation method3A film catalyst precursor.
Preferably, the mass percentage content of the hydrogen fluoride solution is 30-40%;
or the drying condition is a vacuum environment at 50-70 ℃.
The invention also provides the Pd/AlF3Membrane catalyst or Pd/AlF prepared according to the preparation method3The membrane catalyst is applied to catalyzing the hydrodechlorination reaction of chlorine-containing organic matters.
Preferably, the concentration of the chlorine-containing organic matters is 1000-5000 ppm.
According to the membrane catalyst and the preparation method thereof, the palladium-containing composite aluminum fluoride membrane layer with larger specific surface area is prepared, so that the catalytic activity of the catalyst is improved; active metal palladium is added when the film catalyst precursor is prepared, and a surfactant is added, so that metal ions on the surface of the catalyst are dispersed more uniformly, and active metal palladium sintering is reduced; the metal auxiliary agent is added to improve the surface acidity and alkalinity of the membrane catalyst, so that the catalytic performance is improved, a reaction substrate R115 is easier to enrich on the surface of the membrane catalyst, better conditions are provided for converting subsequent reaction into R125, conversion of trace R115 can be catalyzed, and purification of R125 gas containing trace R115 becomes possible.
Drawings
FIG. 1 is a schematic macrostructure diagram of a porous ceramic in an example of the present invention.
FIG. 2 is a schematic view showing the microstructure of a porous ceramic according to an embodiment of the present invention.
Fig. 3 is a schematic structural view of a membrane catalyst according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In order to make the description of the present disclosure more complete and complete, the following description is given for illustrative purposes with respect to the embodiments and examples of the present invention; it is not intended to be the only form in which the embodiments of the invention may be practiced or utilized. The embodiments are intended to cover the features of the various embodiments as well as the method steps and sequences for constructing and operating the embodiments. However, other embodiments may be utilized to achieve the same or equivalent functions and step sequences.
In the specification, R115 is CFC-115, pentafluoro-monochloroethane; r125 is CFC-125, pentafluoroethane.
Precursor preparation examples
The embodiment of the invention provides Pd/AlF3The preparation method of the film catalyst precursor comprises the following steps:
s101, slowly and dropwise adding an acid solvent into the polar organic solvent under the condition that the pH value is 6.5-7.5 to obtain a mixed solvent.
The polar organic solvent can be absolute ethyl alcohol, the acid solvent is one of hydrochloric acid, nitric acid or acetic acid, and the mass percentage of the acid solvent is 36-70%. Preferably, the acid solvent is concentrated nitric acid with the mass percentage of 67%.
S102, respectively adding aluminum alkoxide, metal additive salt, chloropalladate solution and surfactant into the mixed solvent, and refluxing in a constant-temperature water bath at 50-70 ℃ to obtain the palladium-containing composite sol.
Wherein the aluminum alkoxide is aluminum isopropoxide or aluminum butoxide, and the metal auxiliary salt comprises at least two of chloride or nitrate of zinc, chromium, nickel and tin; preferably, the aluminum alkoxide is aluminum isopropoxide and the metal promoter salt comprises two of zinc chloride, chromium chloride, nickel chloride, and tin chloride.
Wherein the mass ratio of the aluminum in the aluminum alkoxide to the metal additives in the metal additive salt is 100: (0.5 to 3), wherein the ratio of the molar amount of palladium in the chloropalladate solution to the molar amount of the surfactant is 1: (50-80). Preferably, the concentration of the metal palladium in the chloropalladate solution is 0.010g/mL, and the addition volume of the chloropalladate solution is 2mL to 10 mL.
Wherein the surfactant is Cetyl Trimethyl Ammonium Bromide (CTAB); and the refluxing time of the constant-temperature water bath is 10-15 hours.
S103, placing the porous ceramic in the palladium-containing composite sol for dipping, drying and roasting to obtain Pd/AlF3A film catalyst precursor.
The porous ceramic material with the pore diameter and the high open porosity is prepared by taking high-quality raw materials such as corundum, silicon carbide and cordierite as main materials and through molding and a special high-temperature sintering process, has the advantages of high temperature resistance, high pressure resistance, acid corrosion resistance, alkali corrosion resistance and organic medium corrosion resistance, good biological inertia, controllable pore structure, high open porosity, long service life, good product regeneration performance and the like. In addition, the base material has stable property, so that the coating can be recycled and regenerated repeatedly even if the coating falls off. Specifically, the structure and SEM images of the porous ceramic are shown in FIGS. 1 and 2.
Wherein the dipping temperature is 50-60 ℃, and the dipping time is 10-15 hours.
Wherein the steps of immersing, drying and calcining the porous ceramic in the palladium-containing composite sol are repeated for a plurality of times, for example, for six times.
Wherein the roasting temperature is 300-550 ℃.
Pd/AlF obtained according to the above preparation method3The film catalyst precursor contains active metal palladium, and in order to prevent the palladium-containing composite sol supported on the porous ceramic by impregnation from being sintered at the time of firing, it is necessary to further disperse the active metal palladium on the porous ceramic, and therefore, a surfactant is added in the embodiment of the present invention.
The surfactant is decomposed in the roasting process, the metal auxiliary agent forms corresponding metal auxiliary agent oxide in the roasting process, and the palladium chloride acid forms palladium oxide in the roasting process.
Pd/AlF obtained according to the above preparation method3Use of film catalyst precursor in further preparation of Pd/AlF3A membrane catalyst.
Pd/AlF prepared according to the above method3The film catalyst precursor includes: the composite coating comprises a porous ceramic layer and a porous composite layer laminated on the surface of the porous ceramic layer, wherein the porous composite layer comprises aluminum oxide, metal auxiliary oxide and palladium oxide, and the metal auxiliary oxide comprises at least two of zinc oxide, chromium oxide, nickel oxide or tin oxide.
Specifically, the mass ratio of the aluminum in the aluminum oxide to each metal additive in the metal additive oxide is 100: (0.5-3), and the thickness of the porous composite layer is 440-560 μm.
Preparation examples of Membrane catalysts
The embodiment of the invention also provides Pd/AlF3The preparation method of the membrane catalyst comprises the following steps:
s201, preparing Pd/AlF3A film catalyst precursor.
The preparation method of the precursor is specifically referred to the above embodiments, and is not described in detail herein.
S202, the obtained Pd/AlF3Placing the film catalyst precursor into a hydrogen fluoride solution, soaking for 0.5-2 hours in a water bath at 50-70 ℃, and then carrying outPd/AlF3The film catalyst precursor is washed to neutrality and dried.
Wherein the mass percentage of the hydrogen fluoride solution is 30-40%, and the drying condition is a vacuum environment at 50-70 ℃.
S203, introducing hydrogen to the Pd/AlF at the temperature of 380-400 DEG C3Reduction of film catalyst precursor to obtain Pd/AlF3A membrane catalyst.
Pd/AlF obtained according to the above preparation method3The structure of the membrane catalyst is shown in fig. 3, and the membrane catalyst comprises a porous ceramic layer 1, a porous palladium-containing composite alumina layer 2, and a porous palladium-containing composite alumina layer 3, which are sequentially laminated.
Pd/AlF obtained according to the above preparation method3The surface area of the membrane catalyst is 180-220 m2/g。
Measured by an ICP emission spectrometer (inductively coupled plasma spectrometer), and the Pd/AlF obtained by the preparation method3The palladium loading capacity of the membrane catalyst is 1-5%, preferably, the palladium loading capacity is 1-3%.
Pd/AlF prepared according to the above method3The membrane catalyst comprises a porous ceramic layer 1, a porous palladium-containing composite alumina layer 2 stacked on the surface of the porous ceramic layer 1, and a porous palladium-containing composite aluminum fluoride layer 3 stacked on the surface of the porous palladium-containing composite alumina layer 2, wherein the porous palladium-containing composite alumina layer 2 comprises alumina, a metal assistant oxide and metal palladium, the porous palladium-containing composite aluminum fluoride layer 3 comprises aluminum fluoride, a metal assistant oxide and metal palladium, and the porous palladium-containing composite alumina layer 2 or the metal assistant oxide in the porous palladium-containing composite aluminum fluoride layer 3 comprises at least two of zinc oxide, chromium oxide, nickel oxide and tin oxide.
Wherein, the Pd/AlF3The surface area of the membrane catalyst is 180-220 m2(ii)/g; the thickness of the porous palladium-containing composite aluminum oxide layer 2 is 220-280 μm, and the thickness of the porous palladium-containing composite aluminum fluoride layer 3 is 220-280 μm; the Pd/AlF3The palladium loading capacity of the membrane catalyst is 1-5%; in a porous palladium-containing composite alumina layerThe mass ratio of the aluminum in the aluminum oxide to the metal additives in the metal additive oxide is 100: (0.5 to 3); in the porous palladium-containing composite aluminum fluoride layer, the mass ratio of aluminum in the aluminum fluoride to each metal auxiliary in the metal auxiliary oxide is 100: (0.5 to 3).
Compared with the prior art, the membrane catalyst and the preparation method thereof provided by the embodiment of the invention have the following differences: (1) porous ceramic is used as a carrier, and the catalytic activity of the catalyst is improved by preparing a palladium-containing composite aluminum fluoride membrane layer with a large specific surface area; (2) compared with the prior art that a composite sol without active metal palladium and a precursor without metal palladium are prepared, and the precursor is soaked in a hydrogen fluoride solution and dried and then placed in a chloropalladate solution to adsorb metal palladium, the membrane catalyst provided by the embodiment of the invention is added with active metal palladium in the process of preparing the composite sol, and the prepared composite sol and the precursor both contain metal palladium, so that each metal can be uniformly distributed on a catalyst membrane layer, more active sites are provided, a foundation is provided for improving the performance, and the surface tension among metal ions is increased and the agglomeration is reduced by adding a surfactant, so that the sintering phenomenon of the active metal palladium in the roasting process is reduced, and the effect of the traditional hydrogenation dechlorination catalyst can be achieved by using a small amount of palladium; (3) the novel metal auxiliary agent is adopted, and the acid-base property of the surface of the membrane catalyst is improved by adding the novel metal auxiliary agent (comprising at least two of chloride or nitrate of zinc, chromium, nickel and tin), so that a reaction substrate is easier to enrich on the surface of the membrane catalyst, and the conversion efficiency of the membrane catalyst is improved.
Example 1
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 7.5, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 0.5 part of CrCl3(metal mass ratio) 0.5 part of ZnCl2(metal mass ratio), 2mL of palladium chloride acid solution (palladium concentration is 0.010g/mL), and 0.01 mol of CTAB (cetyl trimethyl ammonium bromide), and refluxing in a constant-temperature water bath at 50 ℃ for 10h to obtain the palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in water bath at 50 ℃ for 2H, washing to neutrality, vacuum drying at 60 ℃, and carrying out H2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with 1.2 percent of Pd loading3Composite membrane catalyst having a measured surface area of 184.67m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Example 2
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 6.5, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 2 parts of NiCl2(metal mass ratio) 2.5 parts of ZnCl2(metal mass ratio), 6mL of palladium chloride acid solution (palladium concentration is 0.010g/mL), and 0.04 mol of CTAB (cetyl trimethyl ammonium bromide), and refluxing in a constant-temperature water bath at 55 ℃ for 15h to obtain the palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in water bath at 50 deg.C for 0.5H, washing to neutrality, vacuum drying at 50 deg.C, and drying with hydrogen peroxide solution2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with 1.94 percent of Pd loading3Composite membrane catalyst having a measured surface area of 201.59m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Example 3
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 7, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 2.5 parts of SnCl4(metal mass ratio) 3 parts of ZnCl2(metal mass ratio), 10mL of palladium chloride acid solution (palladium concentration is 0.010g/mL), 0.1 mol of CTAB (cetyl trimethyl ammonium bromide), refluxing in a constant temperature water bath at 60 ℃ for 14h to obtain the palladium-containing solutionAnd (4) compounding the sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in water bath at 65 ℃ for 1H, washing to neutrality, vacuum drying at 70 ℃, and performing H2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with Pd loading of 2.93%3Composite membrane catalyst having a measured surface area of 210.35m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Example 4
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 7, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 2.5 parts of CrCl3(metal mass ratio) 0.5 part of NiCl2(metal mass ratio), 8mL of chloropalladate solution (palladium concentration is 0.010g/mL), and 0.05 mol of CTAB (cetyl trimethyl ammonium bromide), and refluxing in a constant-temperature water bath at 55 ℃ for 12h to obtain the palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in water bath at 60 ℃ for 2H, washing to neutrality, vacuum drying at 55 ℃, and carrying out H2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with Pd loading of 2.53 percent3Composite membrane catalyst having a measured surface area of 202.45m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Example 5
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 6.5, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 3 parts of SnCl4(palladium to Metal ratio by mass) 3 parts of NiCl2(metal mass ratio), 8mL of chloropalladate solution (concentration of 0.010g/mL), 0.06 mole of CTAB (cetyltrimethylammonium bromide), and heating in a constant temperature water bath at 60 deg.CFlow 13h gave a palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in 70 deg.C water bath for 1.5H, washing to neutrality, vacuum drying at 65 deg.C, and performing vacuum drying with hydrogen peroxide solution2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with Pd loading of 2.41 percent3Composite membrane catalyst having a measured surface area of 206.94m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Example 6
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 7, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 0.5 part of SnCl4(metal mass ratio) 3 parts of CrCl3(metal mass ratio), 4mL of palladium chloride acid solution (palladium concentration is 0.010g/mL), and 0.03 mol of CTAB (cetyl trimethyl ammonium bromide), and refluxing in a constant-temperature water bath at 55 ℃ for 11h to obtain the palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in water bath at 55 deg.C for 0.5H, washing to neutrality, vacuum drying at 70 deg.C, and drying with hydrogen2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with 1.86 percent of Pd loading3Composite membrane catalyst having a measured surface area of 195.18m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Comparative example 1
AlF3Preparation of the carrier: weighing 4.5g of commercial gamma-A12O3Dissolving in 60mL distilled water, dropwise adding 35 wt.% HF solution 12mL, stirring strongly in 55 deg.C water bath for 12 hr, filtering the obtained white precipitate, washing to neutrality, vacuum drying at 70 deg.C, and drying at 300 deg.C N2Roasting for 6 hours in the atmosphere to obtain the surface area of 115.42m2Per gram of aluminum fluoride.
Preparation of a hydrodechlorination catalyst: 2.5g of the above AlF were weighed3Accurately transferring a chloropalladate solution (with the concentration of 0.010g/m1) with the corresponding volume of 5 percent of loading capacity, stirring and soaking in a water bath at 50 ℃ for 2 hours, raising the temperature of the water bath, continuing to soak for 9 hours, and evaporating to dryness; drying the sample, and roasting at 400 deg.C in a roasting furnace for 4H, H2Reduction at 400 ℃ in atmosphere to obtain Pd/AlF3A catalyst.
Comparative example 2
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 6.5, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 3 parts of YCl3(metal mass ratio) 3 parts of CrCl3(metal mass ratio), 8mL of chloropalladate solution (palladium concentration is 0.010g/mL), and 0.06 mol of CTAB (cetyl trimethyl ammonium bromide), and refluxing in a constant-temperature water bath at 60 ℃ for 13h to obtain the palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in 70 deg.C water bath for 1.5H, washing to neutrality, vacuum drying at 65 deg.C, and performing vacuum drying with hydrogen peroxide solution2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with Pd loading of 2.56 percent3Composite membrane catalyst having a measured surface area of 205.68m2(ii) in terms of/g. (the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Comparative example 3
Preparation of a film catalyst precursor: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 6.5, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 3 parts of NiCl2(metal mass ratio) 3 parts of SnCl4(metal mass ratio), i.e., Al: ni: and (3) refluxing the Sn (100: 3: 3) in a constant-temperature water bath at 55 ℃ for 13h to obtain sol, putting the porous ceramic into the sol, soaking, drying and roasting, and repeating the steps for six times to obtain the precursor of the membrane catalyst carrier.
AlF3Preparation of a membrane catalyst carrier: placing the precursor of the membrane catalyst carrier in 35wt% HF solution is soaked in water bath at 50 ℃ for 2h, washed to be neutral, dried in vacuum at 60 ℃ to prepare AlF3 membrane catalyst carrier, and the measured surface area of the catalyst is 185.12m2/g。
Pd/AlF3Membrane catalyst: placing the AlF3 membrane catalyst carrier in a chloropalladate solution (the concentration is 0.0128/m1), and stirring and soaking the AlF3 membrane catalyst carrier in a water bath at 50 ℃ for 5 hours; drying, roasting at 350 deg.C for 5 hr, H2Reduction at 400 ℃ in atmosphere to obtain Pd/AlF3The Pd loading capacity of the membrane catalyst is 3.89% measured by an ICP emission spectrometer (inductively coupled plasma spectrometer).
Comparative example 4
Preparation of a film catalyst precursor: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 7, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 5 parts of CrCl3(metal mass ratio) 0.5 part of SnCl3(metal mass ratio), i.e., Al: cr: and (3) refluxing the Sn (100: 5: 0.5) in a constant-temperature water bath at 70 ℃ for 10 hours to obtain sol, putting the porous ceramic into the sol, soaking, drying and roasting, and repeating the steps for six times to obtain the precursor of the membrane catalyst carrier.
AlF3Preparation of a membrane catalyst carrier: placing the film catalyst carrier precursor into 35 wt.% of HF solution, soaking for 2h in water bath at 50 ℃, washing to neutrality, and drying in vacuum at 65 ℃ to obtain AlF3A membrane catalyst support having a measured catalyst surface area of 193.84m2/g。
Pd/AlF3Membrane catalyst: placing the AlF3 membrane catalyst carrier in a chloropalladate solution (the concentration is 0.0128/m1), and stirring and soaking in a water bath at 45 ℃ for 8 hours; drying, calcining at 300 deg.C for 7H, H2Reduction at 400 ℃ in atmosphere to obtain Pd/AlF3The Pd loading capacity of the membrane catalyst is 4.83 percent which is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer.
Comparative example 5
Preparation of palladium-containing composite sol: slowly dropwise adding concentrated nitric acid (67 percent by weight) into absolute ethyl alcohol, uniformly stirring, controlling the pH value to be 7, and then adding 100 parts of aluminum isopropoxide (metal mass ratio) and 5 parts of SnCl4(metal mass ratio) 5 parts of CrCl3(mass ratio of metals)) 4mL of chloropalladate solution (the concentration is 0.010g/mL), 0.03 mol of CTAB (cetyl trimethyl ammonium bromide), and refluxing in a constant-temperature water bath at 55 ℃ for 11h to obtain the palladium-containing composite sol.
Pd/AlF3Preparing a composite membrane catalyst: and (3) placing the porous ceramic into composite sol containing palladium for dipping, drying and roasting, and repeating for six times to prepare the precursor of the membrane catalyst. Soaking the film catalyst precursor in 35 wt.% HF solution in water bath at 55 deg.C for 0.5H, washing to neutrality, vacuum drying at 70 deg.C, and drying with hydrogen2Reducing at 400 ℃ in atmosphere to obtain Pd/AlF with 1.91 percent of Pd loading3Composite membrane catalyst having a measured catalyst surface area of 198.58m2/g。
(the loading amount is measured by an ICP emission spectrometer, namely an inductively coupled plasma spectrometer).
Application example
Each of the Pd/AlF prepared in comparative example 1, comparative example 2, comparative example 3, comparative example 4, comparative example 5, example 2, example 4, and example 5 was mixed3Catalyst or Pd/AlF3The composite membrane catalyst is subjected to R125 purification and impurity removal (trace removal of CFC-115) hydrodechlorination reaction, and the performance of each catalyst is evaluated, wherein Pd/AlF3Composite membrane catalyst in gas volume ratio H2:N2Pretreating for 6H at 350 ℃ in an atmosphere of 1:2, and introducing H2And a mixed gas of R125 containing a trace amount of R115, the volume ratio of the reactants being H2The organic gas is 1:50, the contact time is 4-6 s, the reaction temperature is 300-350 ℃, and the experimental results after 10h of catalytic reaction are evaluated are shown in table 1. The catalyst of example 4 was run over 800h and the R115 content was 25ppm after reaction.
TABLE 1 Performance of the examples in the CFC-115 hydrodechlorination experiment
The above comparative examples differ from the embodiments of the present invention in that: the catalyst of comparative example 1 did not use porous ceramic as the support; comparative example 2 does not employ the novel metal additive of the example of the present invention; neither comparative example 3 nor comparative example 4 had the process improvement of the inventive example; in comparative example 5, the mass ratio of the metal aluminum to each metal additive in the metal additive salt is not 100: (0.5-3), as can be seen from table 1, the CFC-115 conversion rates of the embodiments 2, 4 and 5 are significantly higher than those of the comparative examples 1 to 5, that is, the porous ceramic is used as the carrier to prepare the palladium-containing composite aluminum fluoride membrane layer with a large specific surface area, so that the catalytic activity of the catalyst is improved; for active metal palladium, the combination of metal auxiliary agents containing zinc, chromium, nickel or tin improves the catalytic activity of the catalyst; in the process of preparing the catalyst precursor, metal palladium and metal auxiliary agents are added simultaneously, and all metals are uniformly dispersed under the action of the surfactant, so that the catalytic activity of the catalyst is also improved. Taken together, the new metal promoters and process improvements demonstrate a synergistic effect that results in membrane catalysts of examples 2, 4 and 5 having high catalytic activity in catalyzing the conversion of trace amounts of CFC-115.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. Pd/AlF3A film catalyst precursor, wherein the catalyst precursor comprises: the composite coating comprises a porous ceramic layer and a porous composite layer laminated on the surface of the porous ceramic layer, wherein the porous composite layer comprises aluminum oxide, metal auxiliary oxide and palladium oxide, and the metal auxiliary oxide comprises at least two of zinc oxide, chromium oxide, nickel oxide or tin oxide.
2. Pd/AlF according to claim 13A precursor of a film catalyst, characterized in that the ratio of the mass of aluminum in the alumina to the mass of each metal promoter in the metal promoter oxide is 100: (0.5 to 3);
and/or the thickness of the porous composite layer is 440-560 μm.
3. Pd/AlF3A method of preparing a precursor for a film catalyst, the method comprising:
slowly dripping an acid solvent into the polar organic solvent under the condition that the pH value is 6.5-7.5 to obtain a mixed solvent;
respectively adding aluminum alkoxide, metal additive salt, chloropalladate solution and surfactant into the mixed solvent, and refluxing in a constant-temperature water bath at 50-70 ℃ to obtain palladium-containing composite sol;
placing the porous ceramic in the palladium-containing composite sol for dipping, drying and roasting to obtain Pd/AlF3A film catalyst precursor;
wherein the metal additive salt comprises at least two of chloride or nitrate of zinc, chromium, nickel and tin.
4. Pd/AlF according to claim 33The preparation method of the film catalyst precursor is characterized in that the mass ratio of the mass of aluminum in the aluminum alkoxide to the mass of each metal auxiliary in the metal auxiliary salt is 100: (0.5 to 3);
and/or the ratio of the molar amount of the metallic palladium in the chloropalladate to the molar amount of the surfactant is 1: (50-80);
and/or, the polar organic solvent is absolute ethyl alcohol;
and/or the acid solvent is one of hydrochloric acid, nitric acid or acetic acid, and the mass percentage of the acid solvent is 36-70%;
and/or the aluminum alkoxide is aluminum isopropoxide or aluminum butoxide;
and/or the surfactant is cetyl trimethyl ammonium bromide;
and/or the refluxing time of the constant-temperature water bath is 10-15 hours;
and/or, the steps of immersing, drying and roasting the porous ceramic in the palladium-containing composite sol are repeated for a plurality of times;
and/or the dipping temperature is 50-60 ℃, and the dipping time is 10-15 hours;
and/or the roasting temperature is 300-550 ℃.
5. Pd/AlF3The membrane catalyst is characterized by comprising a porous ceramic layer, a porous palladium-containing composite alumina layer stacked on the surface of the porous ceramic layer and a porous palladium-containing composite aluminum fluoride layer stacked on the surface of the porous palladium-containing composite alumina layer, wherein the porous palladium-containing composite alumina layer comprises alumina, a metal assistant oxide and metal palladium, the porous palladium-containing composite aluminum fluoride layer comprises aluminum fluoride, a metal assistant oxide and metal palladium, and the porous palladium-containing composite alumina layer or the metal assistant oxide in the porous palladium-containing composite aluminum fluoride layer comprises at least two of zinc oxide, chromium oxide, nickel oxide or tin oxide.
6. Pd/AlF according to claim 53Membrane catalyst, characterized in that the Pd/AlF3The surface area of the membrane catalyst is 180-220 m2/g;
Or the thickness of the porous palladium-containing composite aluminum oxide layer is 220-280 μm, and the thickness of the porous palladium-containing composite aluminum fluoride layer is 220-280 μm;
or, the Pd/AlF3The palladium loading capacity of the membrane catalyst is 1-5%;
or in the porous palladium-containing composite aluminum oxide layer, the mass ratio of the aluminum in the aluminum oxide to the metal additives in the metal additive oxide is 100: (0.5 to 3); in the porous palladium-containing composite aluminum fluoride layer, the mass ratio of aluminum in the aluminum fluoride to each metal auxiliary in the metal auxiliary oxide is 100: (0.5 to 3).
7. Pd/AlF3The preparation method of the membrane catalyst is characterized by comprising the following steps:
Pd/AlF3Placing the precursor of the membrane catalyst in a hydrogen fluoride solution, soaking for 0.5-2 hours in a water bath at 50-70 ℃, and then carrying out Pd/AlF3Washing the film catalyst precursor to be neutral and drying;
introducing hydrogen at 380-400 ℃ to react the Pd/AlF3Reduction of film catalyst precursor to obtain Pd/AlF3A membrane catalyst;
wherein, the Pd/AlF3The precursor of the film catalyst is Pd/AlF as described in claim 1 or 23Film catalyst precursor or Pd/AlF prepared according to the preparation method of claim 3 or 43A film catalyst precursor.
8. Pd/AlF according to claim 73The preparation method of the membrane catalyst is characterized in that the mass percentage content of the hydrogen fluoride solution is 30-40%;
or the drying condition is a vacuum environment at 50-70 ℃.
9. The Pd/AlF as set forth in claim 5 or 63Membrane catalyst or Pd/AlF prepared according to the preparation process of claim 7 or 83The membrane catalyst is applied to catalyzing the hydrodechlorination reaction of chlorine-containing organic matters.
10. The use according to claim 9, wherein the concentration of the chlorine-containing organic substance is 1000 to 5000 ppm.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115055208A (en) * | 2022-06-24 | 2022-09-16 | 安庆市长三角未来产业研究院 | Preparation method of two-phase flow catalytic membrane, two-phase flow catalytic membrane and application thereof |
CN118253320A (en) * | 2024-05-31 | 2024-06-28 | 黄山熠能科技有限公司 | Preparation process of 1, 1-difluoroethane dehydrofluorination catalyst |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1943849A (en) * | 2006-10-24 | 2007-04-11 | 云南大学 | Process for preparing glass fiber loaded optic catalyst |
CN101003023A (en) * | 2006-01-19 | 2007-07-25 | 清华大学 | Method for preparing catalyst to purify automobile tail gas |
CN105618033A (en) * | 2015-12-23 | 2016-06-01 | 上海大学 | Method for preparing mesoporous gamma-Al2O3 high-dispersion loaded palladium catalyst |
CN105688890A (en) * | 2016-02-01 | 2016-06-22 | 东莞东阳光科研发有限公司 | Fluorination catalyst and preparation method thereof |
CN109261175A (en) * | 2018-10-18 | 2019-01-25 | 乳源东阳光氟有限公司 | A kind of hydrogenation-dechlorination loading type Pd/AlF3Catalyst and its preparation method and application |
CN109513452A (en) * | 2018-11-29 | 2019-03-26 | 东莞东阳光科研发有限公司 | Film catalyst, its presoma and carrier and preparation method thereof |
-
2019
- 2019-08-28 CN CN201910803269.6A patent/CN110586144A/en active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101003023A (en) * | 2006-01-19 | 2007-07-25 | 清华大学 | Method for preparing catalyst to purify automobile tail gas |
CN1943849A (en) * | 2006-10-24 | 2007-04-11 | 云南大学 | Process for preparing glass fiber loaded optic catalyst |
CN105618033A (en) * | 2015-12-23 | 2016-06-01 | 上海大学 | Method for preparing mesoporous gamma-Al2O3 high-dispersion loaded palladium catalyst |
CN105688890A (en) * | 2016-02-01 | 2016-06-22 | 东莞东阳光科研发有限公司 | Fluorination catalyst and preparation method thereof |
CN109261175A (en) * | 2018-10-18 | 2019-01-25 | 乳源东阳光氟有限公司 | A kind of hydrogenation-dechlorination loading type Pd/AlF3Catalyst and its preparation method and application |
CN109513452A (en) * | 2018-11-29 | 2019-03-26 | 东莞东阳光科研发有限公司 | Film catalyst, its presoma and carrier and preparation method thereof |
Non-Patent Citations (1)
Title |
---|
王浚等: ""Pd/γ-Al2O3复合膜的制备工艺研究"", 《无机材料学报》 * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115055208A (en) * | 2022-06-24 | 2022-09-16 | 安庆市长三角未来产业研究院 | Preparation method of two-phase flow catalytic membrane, two-phase flow catalytic membrane and application thereof |
CN115055208B (en) * | 2022-06-24 | 2024-05-10 | 安庆市长三角未来产业研究院 | Preparation method of two-phase flow catalytic membrane, two-phase flow catalytic membrane and application thereof |
CN118253320A (en) * | 2024-05-31 | 2024-06-28 | 黄山熠能科技有限公司 | Preparation process of 1, 1-difluoroethane dehydrofluorination catalyst |
CN118253320B (en) * | 2024-05-31 | 2024-08-02 | 黄山熠能科技有限公司 | Preparation process of 1, 1-difluoroethane dehydrofluorination catalyst |
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