CN111659367A - Nano-grade anatase titanium dioxide dispersion liquid, SCR denitration catalyst suspension liquid, preparation method of SCR denitration catalyst suspension liquid and catalytic ceramic filter cylinder - Google Patents
Nano-grade anatase titanium dioxide dispersion liquid, SCR denitration catalyst suspension liquid, preparation method of SCR denitration catalyst suspension liquid and catalytic ceramic filter cylinder Download PDFInfo
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- 239000000725 suspension Substances 0.000 title claims abstract description 137
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 title claims abstract description 97
- 239000003054 catalyst Substances 0.000 title claims abstract description 89
- 239000006185 dispersion Substances 0.000 title claims abstract description 63
- 239000007788 liquid Substances 0.000 title claims abstract description 56
- 239000000919 ceramic Substances 0.000 title claims abstract description 53
- 230000003197 catalytic effect Effects 0.000 title claims abstract description 29
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- 239000002518 antifoaming agent Substances 0.000 claims abstract description 47
- 239000002270 dispersing agent Substances 0.000 claims abstract description 44
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000000080 wetting agent Substances 0.000 claims abstract description 34
- 239000003381 stabilizer Substances 0.000 claims abstract description 31
- 239000003755 preservative agent Substances 0.000 claims abstract description 30
- 230000002335 preservative effect Effects 0.000 claims abstract description 30
- 150000001875 compounds Chemical class 0.000 claims description 32
- 238000002156 mixing Methods 0.000 claims description 23
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 claims description 21
- 238000000034 method Methods 0.000 claims description 20
- 239000002245 particle Substances 0.000 claims description 17
- 229910052720 vanadium Inorganic materials 0.000 claims description 13
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims description 13
- -1 polydimethylsiloxane Polymers 0.000 claims description 12
- 239000012752 auxiliary agent Substances 0.000 claims description 11
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 10
- 238000000227 grinding Methods 0.000 claims description 10
- 229910052750 molybdenum Inorganic materials 0.000 claims description 10
- 239000011733 molybdenum Substances 0.000 claims description 10
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 10
- 229910052721 tungsten Inorganic materials 0.000 claims description 10
- 239000010937 tungsten Substances 0.000 claims description 10
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- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 6
- 239000002202 Polyethylene glycol Substances 0.000 claims description 6
- 229920001400 block copolymer Polymers 0.000 claims description 6
- 239000004205 dimethyl polysiloxane Substances 0.000 claims description 6
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims description 6
- 229920001223 polyethylene glycol Polymers 0.000 claims description 6
- 229920000142 Sodium polycarboxylate Polymers 0.000 claims description 5
- GVGUFUZHNYFZLC-UHFFFAOYSA-N dodecyl benzenesulfonate;sodium Chemical compound [Na].CCCCCCCCCCCCOS(=O)(=O)C1=CC=CC=C1 GVGUFUZHNYFZLC-UHFFFAOYSA-N 0.000 claims description 5
- JKQOBWVOAYFWKG-UHFFFAOYSA-N molybdenum trioxide Inorganic materials O=[Mo](=O)=O JKQOBWVOAYFWKG-UHFFFAOYSA-N 0.000 claims description 5
- 229940080264 sodium dodecylbenzenesulfonate Drugs 0.000 claims description 5
- 239000004721 Polyphenylene oxide Substances 0.000 claims description 4
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 4
- 229910021529 ammonia Inorganic materials 0.000 claims description 4
- 229920003086 cellulose ether Polymers 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 4
- 229920000570 polyether Polymers 0.000 claims description 4
- 229920002503 polyoxyethylene-polyoxypropylene Polymers 0.000 claims description 4
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 4
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 4
- PUPZLCDOIYMWBV-UHFFFAOYSA-N (+/-)-1,3-Butanediol Chemical compound CC(O)CCO PUPZLCDOIYMWBV-UHFFFAOYSA-N 0.000 claims description 3
- HPNMFZURTQLUMO-UHFFFAOYSA-N diethylamine Chemical compound CCNCC HPNMFZURTQLUMO-UHFFFAOYSA-N 0.000 claims description 3
- VJWGHGJYLCJIEK-UHFFFAOYSA-N 1,4-bis(6-methylheptoxy)-1,4-dioxobutane-2-sulfonic acid Chemical compound CC(C)CCCCCOC(=O)CC(S(O)(=O)=O)C(=O)OCCCCCC(C)C VJWGHGJYLCJIEK-UHFFFAOYSA-N 0.000 claims description 2
- 238000005260 corrosion Methods 0.000 claims 1
- 230000007797 corrosion Effects 0.000 claims 1
- 239000003112 inhibitor Substances 0.000 claims 1
- 239000007787 solid Substances 0.000 abstract description 10
- 230000000694 effects Effects 0.000 abstract description 7
- 230000008901 benefit Effects 0.000 abstract description 6
- 239000011248 coating agent Substances 0.000 abstract description 6
- 238000000576 coating method Methods 0.000 abstract description 6
- 239000000306 component Substances 0.000 description 39
- 238000003756 stirring Methods 0.000 description 32
- 239000007864 aqueous solution Substances 0.000 description 18
- 239000003546 flue gas Substances 0.000 description 18
- 230000008569 process Effects 0.000 description 18
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 17
- UNTBPXHCXVWYOI-UHFFFAOYSA-O azanium;oxido(dioxo)vanadium Chemical compound [NH4+].[O-][V](=O)=O UNTBPXHCXVWYOI-UHFFFAOYSA-O 0.000 description 17
- 238000012360 testing method Methods 0.000 description 17
- XAYGUHUYDMLJJV-UHFFFAOYSA-Z decaazanium;dioxido(dioxo)tungsten;hydron;trioxotungsten Chemical compound [H+].[H+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O XAYGUHUYDMLJJV-UHFFFAOYSA-Z 0.000 description 16
- 239000000428 dust Substances 0.000 description 15
- 239000008367 deionised water Substances 0.000 description 14
- 229910021641 deionized water Inorganic materials 0.000 description 14
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 9
- 235000011114 ammonium hydroxide Nutrition 0.000 description 9
- 239000000203 mixture Substances 0.000 description 9
- 230000001105 regulatory effect Effects 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- 239000011259 mixed solution Substances 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 6
- QGAVSDVURUSLQK-UHFFFAOYSA-N ammonium heptamolybdate Chemical compound N.N.N.N.N.N.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.[Mo].[Mo].[Mo].[Mo].[Mo].[Mo].[Mo] QGAVSDVURUSLQK-UHFFFAOYSA-N 0.000 description 5
- 239000000654 additive Substances 0.000 description 4
- 230000000996 additive effect Effects 0.000 description 4
- 239000000835 fiber Substances 0.000 description 4
- 239000010936 titanium Substances 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000779 smoke Substances 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 2
- YZYASTRURKBPPS-UHFFFAOYSA-N C(CCC(=O)OCCCCCC(C)C)(=O)OCCCCCC(C)C.[Na] Chemical compound C(CCC(=O)OCCCCCC(C)C)(=O)OCCCCCC(C)C.[Na] YZYASTRURKBPPS-UHFFFAOYSA-N 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 239000013530 defoamer Substances 0.000 description 2
- 238000005189 flocculation Methods 0.000 description 2
- 230000016615 flocculation Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
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- BDHFUVZGWQCTTF-UHFFFAOYSA-M sulfonate Chemical compound [O-]S(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-M 0.000 description 2
- 239000004408 titanium dioxide Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 241000282414 Homo sapiens Species 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000003002 pH adjusting agent Substances 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
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- 238000011069 regeneration method Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 231100000820 toxicity test Toxicity 0.000 description 1
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
- B01J21/063—Titanium; Oxides or hydroxides thereof
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/0027—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours with additional separating or treating functions
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
- B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
- B01D46/2411—Filter cartridges
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
- B01D53/8628—Processes characterised by a specific catalyst
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F33/00—Other mixers; Mixing plants; Combinations of mixers
- B01F33/80—Mixing plants; Combinations of mixers
- B01F33/83—Mixing plants specially adapted for mixing in combination with disintegrating operations
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- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/24—Chromium, molybdenum or tungsten
- B01J23/30—Tungsten
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- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0215—Coating
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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Abstract
The invention belongs to the field of denitration catalysts, and particularly relates to a nano-scale anatase titanium dioxide dispersion liquid, an SCR denitration catalyst suspension liquid, a preparation method of the SCR denitration catalyst suspension liquid and a catalytic ceramic filter cylinder. The present invention provides a catalyst suspension comprising: nano-grade anatase titanium dioxide, an active component, a coagent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water; wherein, the content of the nano-grade anatase titanium dioxide is 2-6%, the content of the stabilizer is 0.01-0.1%, the content of the preservative is 0.1-0.2%, the content of the wetting agent is 0.06-0.2%, the content of the dispersing agent is 0.1-0.4%, and the content of the defoaming agent is 0.02-0.4%. According to the invention, the high-activity denitration catalyst suspension suitable for coating the ceramic filter cylinder is obtained by optimally designing the formula of the catalyst suspension, and the suspension has the advantages of low solid content, low viscosity, high fluidity, strong stability and the like.
Description
Technical Field
The invention belongs to the technical field of denitration catalysts, and particularly relates to a nano-scale anatase titanium dioxide dispersion liquid, an SCR denitration catalyst suspension liquid, a preparation method of the SCR denitration catalyst suspension liquid and a catalytic ceramic filter cylinder.
Background
The rapid development of industrialization also aggravates the environmental deterioration, the environmental problems such as haze and the like are increasingly serious, the industrial smoke emission seriously threatens the health of human beings, although corresponding environmental protection policies are already implemented, the atmospheric environment situation is still very severe, and particularly, the smoke in the non-electric power industry still needs to be treated. The traditional denitration and dust removal process is formed by combining denitration technologies such as SCR/SNCR and the like and dust removal technologies such as electric dust removal technology/electric bag composite dust removal technology/bag type dust removal technology and the like. In the operation process of the traditional process, the difference of process conditions such as denitration temperature, dedusting temperature and the like often occurs, and finally the flue gas treatment effect is not ideal; in addition, traditional flue gas treatment device is bulky, and each device is established ties again and is in the same place for the limited mill in place originally can't satisfy the place requirement at all, can't realize the flue gas and administer.
Aiming at the problems, the integrated process for dedusting and denitrating the flue gas becomes a research and development hotspot for domestic flue gas treatment, wherein the integrated ceramic filter cylinder for dedusting and denitrating is the core of the whole process. The dust removal and denitration integrated composite ceramic fiber filter cylinder is pushed to provide a high-efficiency dust and nitrate integrated core component for flue gas treatment in non-electric power industry, accords with the latest technical guidance of China, and has important significance for the field of flue gas treatment of China. The dust removal and denitration integrated composite ceramic filter cylinder is small in occupied area, integrates a plurality of flue gas treatment processes such as dust removal and denitration, meets the national ultra-clean emission requirement, and is remarkable in economic benefit and social benefit. The ceramic filter has the advantages of high porosity, good acid and alkali resistance, high mechanical strength, high temperature resistance, long service life, easy regeneration and the like, and is widely applied to the field of industrial flue gas dust removal. At present, the industrial flue gas NOx and the dust are purified in a denitration unit and a dust removal unit respectively. How to reduce the flue gas denitration dust removal treatment cost is the key and difficult point in the field. For the cylindrical ceramic filter, most of dust is mainly filtered and removed by a membrane with the diameter of 20-100 mu m on the surface layer, and the porous filter cylinder on the inner layer mainly plays a role in supporting. If the SCR catalyst is loaded on the filter cylinder, a denitration and dedusting dual-function ceramic filter can be formed, and denitration and dedusting integration is realized. The catalyst is of great importance as a denitration core part, but at present, most of domestic catalytic ceramic filter cylinder plants do not master the preparation technology of the SCR denitration catalyst applicable to the catalytic ceramic filter cylinder, and how to develop the SCR denitration catalyst for the catalytic ceramic filter cylinder with high efficiency and low cost is a technical problem to be solved urgently in the domestic denitration field.
Disclosure of Invention
In view of the above, the invention aims to provide a nano-grade anatase titanium dioxide dispersion, an SCR denitration catalyst suspension, a preparation method thereof and a catalytic ceramic filter cartridge.
The invention provides a nano-scale anatase titanium dioxide dispersion liquid for preparing SCR denitration catalyst suspension liquid, which comprises the following components: nano-grade anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and water;
the content of the nano-grade anatase titanium dioxide in the dispersion liquid is 10-30 wt%; the content of the wetting agent in the dispersion liquid is 0.3-1 wt%; the content of the dispersing agent in the dispersion liquid is 0.5-2 wt%; the content of the defoaming agent in the dispersion liquid is 0.1-2 wt%.
Preferably, the D50 particle size of the nano-scale anatase titanium dioxide in the dispersion is less than or equal to 500nm, and the D90 particle size is less than or equal to 800 nm.
Preferably, the wetting agent comprises one or more of sodium diisooctyl succinate sulfonate, sodium dodecylbenzene sulfonate and polyoxyethylene polyoxypropylene block copolymer;
the dispersant comprises a sodium polycarboxylate dispersant, polyethylene glycol, polyvinyl alcohol and TiO-containing dispersant2One or more of block copolymers of an affinity group;
the defoaming agent comprises one or more of polydimethylsiloxane defoaming agent, ethylene glycol siloxane defoaming agent and polyether modified silicon defoaming agent.
The invention provides an SCR denitration catalyst suspension, which comprises: nano-grade anatase titanium dioxide, an active component, a coagent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water;
the active component is a soluble vanadium source compound; the active auxiliary agent is a soluble tungsten source compound and/or a soluble molybdenum source compound; with V2O5Soluble vanadium source compound calculated by WO3Soluble tungsten source compound in MoO3Soluble molybdenum source compound and in TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: (0-2): (0-2): (2-9);
the content of the nano-grade anatase titanium dioxide in the suspension is 2-6 wt%; the content of the stabilizer in the suspension is 0.01-0.1 wt%; the content of the preservative in the suspension is 0.1-0.2 wt%; the content of the wetting agent in the suspension is 0.06-0.2 wt%; the content of the dispersing agent in the suspension is 0.1-0.4 wt%; the content of the defoaming agent in the suspension is 0.02-0.4 wt%.
Preferably, the stabilizer comprises ammonia and/or cellulose ether.
Preferably, the preservative comprises one or more of ethanol, propylene glycol, butylene glycol and diethylamine.
Preferably, the pH value of the suspension is 9-12.
The invention provides a preparation method of the SCR denitration catalyst suspension liquid, which comprises the following steps:
a) uniformly mixing the nano-scale anatase titanium dioxide, an active component, an active auxiliary agent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water to obtain the SCR denitration catalyst suspension.
Preferably, the step a) specifically comprises:
a1) mixing and grinding the nano-scale anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and part of water to obtain nano-scale anatase titanium dioxide dispersion liquid;
a2) and uniformly mixing the nano-scale anatase titanium dioxide dispersion liquid, the active component, the active auxiliary agent, the stabilizer, the preservative and the balance of water to obtain the SCR denitration catalyst suspension.
The invention provides a catalytic ceramic filter cylinder which comprises a ceramic filter cylinder body and a catalytic component loaded on the ceramic filter cylinder body, wherein the catalytic component is formed by drying an SCR denitration catalyst suspension liquid coated on the ceramic filter cylinder body in the technical scheme at the temperature of 90-110 ℃.
Compared with the prior art, the invention provides a nano-scale anatase titanium dioxide dispersion liquid, an SCR denitration catalyst suspension liquid, a preparation method thereof and a catalytic ceramic filter cylinder. The present invention provides a catalyst suspension comprising: nano-grade anatase titanium dioxide, an active component, a coagent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water; the active component is a soluble vanadium source compound; the active auxiliary agent is a soluble tungsten source compound and/or a soluble molybdenum source compound; with V2O5Soluble vanadium source compound calculated by WO3Soluble tungsten source compound in MoO3Soluble molybdenum source compound and in TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: (0-2): (0-2): (2-9); the content of the nano-grade anatase titanium dioxide in the suspension is 2-6 wt%; the content of the stabilizer in the suspension is 0.01-0.1 wt%; the content of the preservative in the suspension is 0.1 to0.2 wt%; the content of the wetting agent in the suspension is 0.06-0.2 wt%; the content of the dispersing agent in the suspension is 0.1-0.4 wt%; the content of the defoaming agent in the suspension is 0.02-0.4 wt%. According to the invention, the high-activity denitration catalyst suspension suitable for coating the ceramic filter cylinder is obtained by optimally designing the formula of the catalyst suspension, the catalyst liquid is stable suspension, and has the advantages of low solid content, low viscosity, high fluidity and the like, and after coating, the nano-scale catalyst suspension particles can enter the ceramic filter cylinder with micron-scale pore passages to be adhered to the ceramic filter cylinder ceramic filter tube fibers and are uniformly distributed in the ceramic filter cylinder; when the catalyst suspension is used for preparing the catalytic ceramic filter cylinder, the catalyst suspension is only required to be uniformly coated on the ceramic filter cylinder and then dried at the temperature of 90-110 ℃, secondary high-temperature roasting is not required, and the production cost of preparing the catalytic ceramic filter cylinder by using the catalyst suspension is greatly reduced; in addition, the catalyst suspension has excellent stability, and can be stably stored for more than 1 month without flocculation and sedimentation.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a flow chart of a process for preparing a suspension of SCR denitration catalyst provided in example 1 of the present invention;
FIG. 2 is a temperature-denitration efficiency curve provided in example 5 of the present invention;
FIG. 3 is a plot of space velocity versus denitration efficiency as provided in example 5 of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a nano-scale anatase titanium dioxide dispersion liquid for preparing SCR denitration catalyst suspension liquid, which comprises the following components: nano-grade anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and water;
the content of the nano-grade anatase titanium dioxide in the dispersion liquid is 10-30 wt%; the content of the wetting agent in the dispersion liquid is 0.3-1 wt%; the content of the dispersing agent in the dispersion liquid is 0.5-2 wt%; the content of the defoaming agent in the dispersion liquid is 0.1-2 wt%.
The nano-scale anatase titanium dioxide dispersion provided by the invention comprises nano-scale anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and water. Wherein the D50 particle size of the nano-scale anatase titanium dioxide in the dispersion liquid is preferably less than or equal to 500nm, more preferably less than or equal to 200nm, and most preferably less than or equal to 160 nm; the D90 particle size of the nano-scale anatase titanium dioxide is preferably less than or equal to 800nm, more preferably less than or equal to 600nm, and most preferably less than or equal to 450 nm; the nano-sized anatase titania is preferably contained in the dispersion in an amount of 10 to 30 wt%, specifically 10 wt%, 10.5 wt%, 11 wt%, 11.5 wt%, 12 wt%, 12.5 wt%, 13 wt%, 13.5 wt%, 14 wt%, 14.5 wt%, 15 wt%, 15.5 wt%, 16 wt%, 16.5 wt%, 17 wt%, 17.5 wt%, 18 wt%, 18.5 wt%, 19 wt%, 19.5 wt%, 20 wt%, 20.5 wt%, 21 wt%, 21.5 wt%, 22 wt%, 22.5 wt%, 23 wt%, 23.5 wt%, 24 wt%, 24.5 wt%, 25 wt%, 25.5 wt%, 26 wt%, 26.5 wt%, 27 wt%, 27.5 wt%, 28 wt%, 28.5 wt%, 29 wt%, 29.5 wt%, or 30 wt%.
In the dispersion provided by the present invention, the wetting agent preferably includes one or more of diisooctyl sulfosuccinate, sodium dodecylbenzenesulfonate and polyoxyethylene polyoxypropylene block copolymer. In the present invention, the content of the wetting agent in the dispersion is 0.3 to 1 wt%, specifically 0.3 wt%, 0.35 wt%, 0.4 wt%, 0.45 wt%, 0.5 wt%, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.75 wt%, 0.8 wt%, 0.85 wt%, 0.9 wt%, 0.95 wt%, or 1 wt%.
In the dispersion provided by the invention, the dispersant comprises a sodium polycarboxylate type dispersant, polyethylene glycol, polyvinyl alcohol and TiO-containing2The molecular weight of the dispersant is preferably SN-5040, and the molecular weight of the polyethylene glycol is preferably 200-400. In the present invention, the content of the dispersant in the dispersion is 0.5 to 2 wt%, specifically 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt%, or 2 wt%.
In the dispersion provided by the invention, the defoaming agent comprises one or more of polydimethylsiloxane defoaming agent, ethylene glycol siloxane defoaming agent and polyether modified silicon defoaming agent; the polydimethylsiloxane defoamer is preferably available under the brand name XP-123. In the present invention, the content of the defoaming agent in the dispersion is 0.1 to 2 wt%, specifically 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt%, or 2 wt%.
According to the invention, the titanium dioxide dispersion liquid with low solid content, small viscosity, high fluidity and strong stability is obtained by optimally designing the formula of the dispersion liquid, and the dispersion liquid is very suitable to be used as a preparation raw material of the SCR denitration catalyst suspension liquid.
The invention also provides an SCR denitration catalyst suspension, which comprises: nano-grade anatase titanium dioxide, an active component, a coagent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water;
the active component is a soluble vanadium source compound; the active auxiliary agent is a soluble tungsten source compound and/or a soluble molybdenum source compound; with V2O5Soluble vanadium source compound calculated by WO3Soluble tungsten source for metersCompound of MoO3Soluble molybdenum source compound and in TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: (0-2): (0-2): (2-9);
the content of the nano-grade anatase titanium dioxide in the suspension is 2-6 wt%; the content of the stabilizer in the suspension is 0.01-0.1 wt%; the content of the preservative in the suspension is 0.1-0.2 wt%; the content of the wetting agent in the suspension is 0.06-0.2 wt%; the content of the dispersing agent in the suspension is 0.1-0.4 wt%; the content of the defoaming agent in the suspension is 0.02-0.4 wt%.
The catalyst suspension provided by the invention comprises nano-scale anatase titanium dioxide, an active component, a coagent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water. Wherein the D50 particle size of the nano-scale anatase titanium dioxide is preferably less than or equal to 500nm, more preferably less than or equal to 200nm, and most preferably less than or equal to 160 nm; the D90 particle size of the nano-scale anatase titanium dioxide is preferably less than or equal to 800nm, more preferably less than or equal to 600nm, and most preferably less than or equal to 450 nm; the content of the nano-grade anatase titanium dioxide in the suspension is preferably 2 to 6 wt%, and specifically may be 2 wt%, 2.1 wt%, 2.2 wt%, 2.3 wt%, 2.358 wt%, 2.4 wt%, 2.5 wt%, 2.6 wt%, 2.7 wt%, 3 wt%, 3.2 wt%, 3.5 wt%, 3.7 wt%, 3.718 wt%, 3.784 wt%, 4 wt%, 4.136 wt%, 4.2 wt%, 4.5 wt%, 4.7 wt%, 5 wt%, 5.2 wt%, 5.5 wt%, 5.7 wt%, 6 wt%.
In the catalyst suspension provided by the invention, the active component is a soluble vanadium source compound, and the soluble vanadium source compound includes but is not limited to ammonium metavanadate; the coagent is a soluble tungsten source compound including, but not limited to, ammonium paratungstate and/or ammonium metatungstate and/or a soluble molybdenum source compound including, but not limited to, ammonium heptamolybdate.
In the catalyst suspension provided by the invention, V is2O5Calculated vanadium source compound and WO3The mass ratio of the tungsten source compound is 1: (0 to 2), preferably 1: (0 to 1.5) of,more preferably 1: (0.2-1), specifically 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1: 1; with V2O5Calculated vanadium source compound and calculated as MoO3The mass ratio of the molybdenum source compounds is 1: (0 to 2), preferably 1: (0 to 1.5), more preferably 1: (0.2-1), specifically 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1: 1; with V2O5Vanadium source compound and calculated as TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: (2-9), preferably 1: (2-5), specifically 1:2, 1:2.1, 1:2.3, 1:2.5, 1:2.6, 1:2.8, 1:3, 1:3.1, 1:3.3, 1:3.5, 1:3.6, 1:3.8, 1:4, 1:4.1, 1:4.3, 1:4.5, 1:4.6, 1:4.8 or 1: 5.
In the catalyst suspension provided by the present invention, the stabilizer preferably comprises ammonia and/or a cellulose ether, which is preferably a low viscosity cellulose ether. In the present invention, the content of the stabilizer in the suspension is 0.01 to 0.1 wt%, preferably 0.02 to 0.06 wt%, and specifically may be 0.02 wt%, 0.025 wt%, 0.03 wt%, 0.035 wt%, 0.04 wt%, 0.045 wt%, 0.05 wt%, 0.055 wt%, or 0.06 wt%.
In the catalyst suspension provided by the present invention, the preservative preferably comprises one or more of ethanol, propylene glycol, butylene glycol and diethylamine. In the present invention, the content of the preservative in the suspension is 0.1 to 0.2 wt%, specifically 0.1 wt%, 0.11 wt%, 0.12 wt%, 0.13 wt%, 0.14 wt%, 0.15 wt%, 0.16 wt%, 0.17 wt%, 0.18 wt%, 0.19 wt%, or 0.2 wt%.
In the catalyst suspension provided by the present invention, the wetting agent preferably comprises one or more of sodium diisooctyl succinate sulfonate, sodium dodecylbenzenesulfonate and polyoxyethylene polyoxypropylene block copolymer. In the present invention, the content of the wetting agent in the suspension is 0.06 to 0.2 wt%, specifically 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.0845 wt%, 0.086 wt%, 0.09 wt%, 0.094 wt%, 0.1 wt%, 0.11 wt%, 0.12 wt%, 0.13 wt%, 0.14 wt%, 0.15 wt%, 0.16 wt%, 0.17 wt%, 0.18 wt%, 0.19 wt%, or 0.2 wt%.
In the catalyst suspension provided by the invention, the dispersing agent comprises a sodium polycarboxylate dispersing agent, polyethylene glycol, polyvinyl alcohol and TiO-containing dispersing agent2The molecular weight of the dispersant is preferably SN-5040, and the molecular weight of the polyethylene glycol is preferably 200-400. In the present invention, the content of the dispersant in the suspension is 0.1 to 0.4 wt%, specifically 0.1 wt%, 0.11 wt%, 0.12 wt%, 0.13 wt%, 0.14 wt%, 0.15 wt%, 0.16 wt%, 0.169 wt%, 0.17 wt%, 0.172 wt%, 0.18 wt%, 0.188 wt%, 0.19 wt%, 0.2 wt%, 0.25 wt%, 0.3 wt%, 0.35 wt%, or 0.4 wt%.
In the catalyst suspension provided by the invention, the defoaming agent comprises one or more of polydimethylsiloxane defoaming agent, ethylene glycol siloxane defoaming agent and polyether modified silicon defoaming agent; the polydimethylsiloxane defoamer is preferably available under the brand name XP-123. In the present invention, the content of the defoaming agent in the suspension is 0.02 to 0.4 wt%, specifically 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.0845 wt%, 0.086 wt%, 0.09 wt%, 0.094 wt%, 0.1 wt%, 0.12 wt%, 0.15 wt%, 0.17 wt%, 0.2 wt%, 0.23 wt%, 0.25 wt%, 0.27 wt%, 0.3 wt%, 0.32 wt%, 0.35 wt%, 0.37 wt%, or 0.4 wt%.
In the catalyst suspension provided by the invention, the pH value of the suspension is preferably 9-12, more preferably 9-11, most preferably 9.5-10, and specifically can be 9.5, 9.6, 9.7, 9.8, 9.9 or 10; the solid content of the suspension is preferably 5-10%, more preferably 5.5-6.5%, and specifically can be 5.5%, 5.6%, 5.7%, 5.8%, 5.9%, 6%, 6.1%, 6.2%, 6.3%, 6.4% or 6.5%; the viscosity of the suspension at 25 ℃ is preferably 1-20 mPaS, more preferably 5-9 mPaS, and specifically can be 5mPaS, 5.5mPaS, 6mPaS, 6.5mPaS, 6.8mPaS, 7mPaS, 7.5mPaS, 7.6mPaS, 8mPaS, 8.5mPaS, 8.8mPaS or 9 mPaS. In the present invention, in order to control the pH value of the catalyst suspension within a proper range, a proper amount of pH regulator, including but not limited to ammonia, may be additionally added to the catalyst suspension. In the invention, the solid content refers to the mass percentage of the residual solid after the suspension is completely roasted at 450-550 ℃ in the total mass, namely, the solid content is obtained by calculating the loss on ignition.
The invention also provides a preparation method of the SCR denitration catalyst suspension liquid, which comprises the following steps:
a) uniformly mixing the nano-scale anatase titanium dioxide, an active component, an active auxiliary agent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water to obtain the SCR denitration catalyst suspension.
In the preparation method provided by the invention, the SCR denitration catalyst suspension provided by the invention can be obtained by directly and uniformly mixing the raw materials according to the proportion, and the specific process preferably comprises the following steps:
a1) mixing and grinding the nano-scale anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and part of water to obtain nano-scale anatase titanium dioxide dispersion liquid;
a2) and uniformly mixing the nano-scale anatase titanium dioxide dispersion liquid, the active component, the active auxiliary agent, the stabilizer, the preservative and the balance of water to obtain the SCR denitration catalyst suspension.
In the above preparation steps provided by the present invention, first, the nano-grade anatase titanium dioxide, the wetting agent, the dispersing agent, the defoaming agent and part of the water are mixed and ground uniformly to obtain the nano-grade anatase titanium dioxide dispersion liquid, and the specific mixing and grinding process preferably includes: the preparation method comprises the steps of uniformly mixing a wetting agent, a dispersing agent and water, adding nano-scale anatase titanium dioxide into the obtained mixed solution under a stirring state, fully stirring and mixing, transferring the obtained titanium dioxide mixed solution into grinding equipment for grinding, and finally adding a defoaming agent into the ground mixed solution for mixing to obtain the dispersion liquid. In the invention, the primary particle size of the nano-grade anatase titanium dioxide before grinding is preferably less than or equal to 100nm, and more preferably the particle size is 20-50 nm; the D50 particle size after grinding is preferably less than or equal to 500nm, and the D90 particle size is preferably less than or equal to 800 nm.
In the preparation steps provided by the invention, after the nano-grade anatase titanium dioxide dispersion liquid is obtained, the dispersion liquid, the active component, the active assistant, the stabilizer, the preservative and the balance of water are uniformly mixed according to a preferable formula proportion to obtain the SCR denitration catalyst suspension provided by the invention, wherein the specific mixing process preferably comprises the following steps: a2-1) mixing an active component and an active assistant with part of water respectively to obtain an active component solution and an active assistant solution; a2-2) mixing the active ingredient solution, the coagent solution, and the dispersion; a2-3) mixing the mixed solution obtained by mixing with a stabilizer, a preservative and the rest water to obtain the SCR denitration catalyst suspension. In the present invention, the specific process of step a2-2) preferably comprises: firstly, dispersing the dispersion liquid at a certain rotating speed, then, reducing the rotating speed, adding the active component solution and the active auxiliary agent solution, and after the addition is finished, increasing the rotating speed and continuously mixing for a period of time; the rotating speed of the dispersion liquid during dispersion is preferably 500-1000 r/min, specifically 500r/min, 600r/min, 650r/min, 700r/min, 800r/min, 900r/min or 1000r/min, and the dispersion time is preferably 20-60 min, specifically 20min, 30min, 40min, 50min or 60 min; the rotation speed after being reduced is preferably 100-200 r/min, and can be 100r/min, 120r/min, 150r/min, 180r/min or 20r/min specifically; the rotation speed of the continuous mixing is preferably 500r/min, 600r/min, 700r/min, 800r/min, 900r/min or 1000r/min, and the time of the continuous mixing is preferably 20-60 min, and specifically can be 20min, 30min, 40min, 50min or 60 min.
In the preparation method provided by the invention, after the SCR denitration catalyst suspension is prepared, if the pH value of the catalyst suspension is not within the specified pH value range, a proper amount of pH regulator including but not limited to ammonia water may be further added to the catalyst suspension.
According to the invention, the high-activity denitration catalyst suspension suitable for coating the ceramic filter cylinder is obtained by optimally designing the formula of the catalyst suspension, the catalyst liquid is stable suspension, all components are uniformly distributed, suspended particles are in a nanometer level, the suspension has the advantages of low solid content, small viscosity, high flowability and the like, and after coating, nanometer particles can enter the ceramic filter cylinder with micron-sized pore passages to be adhered to fibers of the ceramic filter cylinder and are uniformly distributed in the ceramic filter cylinder; when the catalyst suspension is used for preparing the catalytic ceramic filter cylinder, the suspension is coated on the ceramic filter cylinder for drying, secondary high-temperature roasting is not needed, and the production cost of the catalytic ceramic filter cylinder is greatly reduced; in addition, the catalyst suspension has excellent stability, and can be stably stored for more than 1 month without flocculation and sedimentation.
The invention also provides a catalytic ceramic filter cylinder which comprises a ceramic filter cylinder body and a catalytic component loaded on the ceramic filter cylinder body, wherein the catalytic component is formed by drying the SCR denitration catalyst suspension coated on the surface of the ceramic filter cylinder body in the technical scheme at the temperature of 90-110 ℃.
The catalytic ceramic filter cylinder provided by the invention comprises a ceramic filter cylinder body and the catalytic component loaded on the ceramic filter cylinder body, so that the catalytic ceramic filter cylinder has excellent denitration performance and has a very wide application prospect in the technical field of denitration and dust removal integration of the catalytic ceramic filter cylinder.
For the sake of clarity, the following examples are given in detail.
Example 1
Referring to the process flow shown in fig. 1, the SCR denitration catalyst suspension is prepared as follows:
(1) preparing nano-grade anatase titanium dioxide dispersion liquid:
the components of the dispersion are designed, and the method specifically comprises the following steps: 0.5 wt% of water-based wetting agent, 1 wt% of water-based dispersant, 22 wt% of nano-grade anatase titanium dioxide, 0.5 wt% of water-based defoaming agent and the balance of deionized water.
According to the composition of the components, the components are uniformly mixed, and the specific process comprises the following steps: uniformly mixing an aqueous wetting agent (sodium dodecyl benzene sulfonate), an aqueous dispersant (sodium polycarboxylate dispersant SN-5040, pH 7.5 of Guangzhou Hengyu chemical Co., Ltd.) and deionized water to form a mixed solution; then adding nano-grade anatase titanium dioxide (P25 of degussa) into the mixed solution under the action of continuous stirring, fully and uniformly stirring, and transferring to grinding equipment for grinding and dispersing for 6 hours; and then adding an aqueous defoaming agent (XP-123 defoaming agent, Hill New Material Co., Ltd., Dongguan city, pH 6.0-9.0) into the ground mixed solution, and fully and uniformly stirring to obtain a nano-scale anatase titanium dioxide dispersion liquid, wherein the mark is SP 22.
The prepared SP22 was subjected to a particle size distribution test in a laser particle sizer, and as a result, D50 was 158nm and D90 was 568 nm.
(2) Preparing SCR denitration catalyst suspension:
designing the composition of the suspension, specifically: 18.8 wt.% of nano-sized anatase titanium dioxide dispersion (SP22), in suspension, as V2O5Calculated ammonium metavanadate as WO3Calculated as ammonium paratungstate and calculated as TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: 0.5: 3, 0.05 wt% of stabilizing agent, 0.12 wt% of preservative, a proper amount of pH regulator and the balance of deionized water.
According to the composition of the components, the components are uniformly mixed, and the specific process comprises the following steps: respectively dissolving an active component (ammonium metavanadate) and an active additive (ammonium paratungstate) in deionized water to obtain an ammonium metavanadate aqueous solution and an ammonium paratungstate aqueous solution; adding the nano-scale anatase titanium dioxide dispersion SP22 into a stirring tank, adjusting the rotation speed to 650r/min, and stirring for 30 min; regulating the rotating speed to 200r/min, adding the ammonium metavanadate aqueous solution and the ammonium paratungstate aqueous solution into a stirring tank, regulating the rotating speed to 600r/min, and stirring for 30 min; adding a suspension stabilizer (20 wt% ammonia water), a suspension preservative (propylene glycol) and deionized water into the stirring tank, and fully and uniformly stirring; finally, adding a pH regulator (20 wt% ammonia water) into the stirring tank to regulate the pH value of the mixed system in the tank to about 9.5 to obtain a denitration catalyst suspension, wherein the mark is V1W0.5Ti3。
Example 2
Preparing SCR denitration catalyst suspension:
designing the composition of the suspension, specifically: 17.2 wt.% nano-sized anatase titanium dioxide dispersion (SP22), in suspension, as V2O5Calculated ammonium metavanadate as WO3Calculated as ammonium paratungstate and calculated as TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: 1:3, 0.05 wt% of stabilizing agent, 0.12 wt% of preservative, a proper amount of pH regulator and the balance of deionized water.
According to the composition of the components, the components are uniformly mixed, and the specific process comprises the following steps: respectively dissolving an active component (ammonium metavanadate) and an active additive (ammonium paratungstate) in deionized water to obtain an ammonium metavanadate aqueous solution and an ammonium paratungstate aqueous solution; adding the nano-scale anatase titanium dioxide dispersion SP22 prepared in the example 1 into a stirring tank, and adjusting the rotating speed to 650r/min to stir for 30 min; regulating the rotating speed to 200r/min, adding the ammonium metavanadate aqueous solution and the ammonium paratungstate aqueous solution into a stirring tank, regulating the rotating speed to 600r/min, and stirring for 30 min; adding a suspension stabilizer (20 wt% ammonia water), a suspension preservative (propylene glycol) and deionized water into the stirring tank, and fully and uniformly stirring; finally, adding a pH regulator (20 wt% ammonia water) into the stirring tank to regulate the pH value of the mixed system in the tank to about 9.5 to obtain a denitration catalyst suspension, wherein the mark is V1W1Ti3。
Example 3
Preparing SCR denitration catalyst suspension:
designing the composition of the suspension, specifically: 18.8 wt.% of nano-sized anatase titanium dioxide dispersion (SP22), in suspension, as V2O5Calculated ammonium metavanadate as WO3Calculated as ammonium paratungstate and calculated as TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: 1:4, 0.05 wt% of stabilizing agent, 0.12 wt% of preservative, a proper amount of pH regulator and the balance of deionized water.
According to the composition of the components, the components are uniformly mixed, and the specific process comprises the following steps: respectively dissolving active component (ammonium metavanadate) and active additive (ammonium paratungstate) in deionized water to obtainTo ammonium metavanadate aqueous solution and ammonium paratungstate aqueous solution; adding the nano-scale anatase titanium dioxide dispersion SP22 prepared in the example 1 into a stirring tank, and adjusting the rotating speed to 650r/min to stir for 30 min; regulating the rotating speed to 200r/min, adding the ammonium metavanadate aqueous solution and the ammonium paratungstate aqueous solution into a stirring tank, regulating the rotating speed to 600r/min, and stirring for 30 min; adding a suspension stabilizer (20 wt% ammonia water), a suspension preservative (propylene glycol) and deionized water into the stirring tank, and fully and uniformly stirring; finally, adding a pH regulator (20 wt% ammonia water) into the stirring tank to regulate the pH value of the mixed system in the tank to about 9.5 to obtain a denitration catalyst suspension, wherein the mark is V1W1Ti4。
Example 4
Preparing SCR denitration catalyst suspension:
designing the composition of the suspension, specifically: 16.9 wt.% nano-sized anatase titanium dioxide dispersion (SP22), in suspension, as V2O5Calculated ammonium metavanadate as WO3Calculated as MoO, ammonium paratungstate3Calculated as ammonium heptamolybdate and as TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: 0.5: 0.5: 3, 0.05 wt% of stabilizing agent, 0.12 wt% of preservative, a proper amount of pH regulator and the balance of deionized water.
According to the composition of the components, the components are uniformly mixed, and the specific process comprises the following steps: respectively dissolving an active component (ammonium metavanadate) and an active additive (ammonium paratungstate and ammonium heptamolybdate) in deionized water to obtain an ammonium metavanadate aqueous solution, an ammonium paratungstate aqueous solution and an ammonium heptamolybdate aqueous solution; adding the nano-scale anatase titanium dioxide dispersion SP22 prepared in the example 1 into a stirring tank, and adjusting the rotating speed to 650r/min to stir for 30 min; regulating the rotating speed to 200r/min, adding the ammonium metavanadate aqueous solution, the ammonium paratungstate aqueous solution and the ammonium heptamolybdate aqueous solution into a stirring tank, and then regulating the rotating speed to 600r/min for stirring for 30 min; adding a suspension stabilizer (20 wt% ammonia water), a suspension preservative (propylene glycol) and deionized water into the stirring tank, and fully and uniformly stirring; finally, a pH adjusting agent (20 wt% ammonia water) was added to the stirred tankAdjusting the pH value of the in-tank mixed system to about 9.5 to obtain a denitration catalyst suspension liquid marked as V1W0.5Mo0.5Ti3。
Example 5
1) The SCR denitration catalyst suspension prepared in examples 1 to 4 was subjected to a solid content test, a viscosity test, a particle size test, and a pH test, and the test results are shown in table 1:
TABLE 1 denitration catalyst suspension physical Property analysis test results
As can be seen from table 1, the particulate matter in the SCR denitration catalyst suspensions prepared in examples 1 to 4 is in the nanometer level, and the suspensions have low solid content and low viscosity.
2) The SCR denitration catalyst suspension prepared in the embodiment 1 to 4 is respectively coated on a ceramic fiber filter cylinder with the diameter of phi 150mm produced by Longjing Kerui according to 9 percent of the weight of a coating sample, and the sample is placed on a denitration performance testing device for carrying out the activity test of the denitration catalyst after being completely dried at 100 to 120 ℃, wherein the specific test process is as follows:
a small sample of the catalyzed ceramic filter cartridge was loaded into a catalyst activity test reactor that could be heated up to 800 ℃ (1500F). The carrier gas N required for the test is passed through an accurate mass flow controller under simulated flue gas2Toxicity test gases NO and oxygen O2Reducing agent NH3And water vapor are input into the reactor, and after the water vapor and the water vapor are fully and uniformly mixed, the concentration change of the toxicity test gas NO before and after the test reaction is carried out. The test conditions are as shown in table 2:
TABLE 2 Smoke parameters testing table
The denitration efficiency (eta) of the catalytic ceramic filter cylinder is calculated according to (1):
in the formula:
C1: when the flue gas treatment system is in operation, the content (mg/Nm) of NOx in the flue gas at the inlet of the flue gas treatment system3);
C2: NOx content (mg/Nm) in flue gas at outlet of flue gas treatment system during flue gas treatment operation3)。
The results of the catalytic ceramic filter cartridge activity tests are shown in fig. 2-3, fig. 2 is a temperature-denitration efficiency curve provided in example 5 of the present invention, and fig. 3 is a space velocity-denitration efficiency curve provided in example 5 of the present invention.
As can be seen from FIGS. 2 and 3, the catalytic ceramic filter cartridge coated with the catalyst suspensions of examples 1 to 4 has very excellent denitration performance.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. A nano-sized anatase titania dispersion for preparing an SCR denitration catalyst suspension, comprising: nano-grade anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and water;
the content of the nano-grade anatase titanium dioxide in the dispersion liquid is 10-30 wt%; the content of the wetting agent in the dispersion liquid is 0.3-1 wt%; the content of the dispersing agent in the dispersion liquid is 0.5-2 wt%; the content of the defoaming agent in the dispersion liquid is 0.1-2 wt%.
2. The nano-sized anatase titania dispersion according to claim 1 wherein the nano-sized anatase titania in the dispersion has a D50 particle size of 500nm or less and a D90 particle size of 800nm or less.
3. The nano-sized anatase titanium dioxide dispersion according to claim 1 wherein the wetting agent comprises one or more of diisooctyl sulfosuccinate, sodium dodecylbenzenesulfonate and polyoxyethylene polyoxypropylene block copolymer;
the dispersant comprises a sodium polycarboxylate dispersant, polyethylene glycol, polyvinyl alcohol and TiO-containing dispersant2One or more of block copolymers of an affinity group;
the defoaming agent comprises one or more of polydimethylsiloxane defoaming agent, ethylene glycol siloxane defoaming agent and polyether modified silicon defoaming agent.
4. An SCR denitration catalyst suspension comprising: nano-grade anatase titanium dioxide, an active component, a coagent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water;
the active component is a soluble vanadium source compound; the active auxiliary agent is a soluble tungsten source compound and/or a soluble molybdenum source compound; with V2O5Soluble vanadium source compound calculated by WO3Soluble tungsten source compound in MoO3Soluble molybdenum source compound and in TiO2The mass ratio of the nano-scale anatase titanium dioxide is 1: (0-2): (0-2): (2-9);
the content of the nano-grade anatase titanium dioxide in the suspension is 2-6 wt%; the content of the stabilizer in the suspension is 0.01-0.1 wt%; the content of the preservative in the suspension is 0.1-0.2 wt%; the content of the wetting agent in the suspension is 0.06-0.2 wt%; the content of the dispersing agent in the suspension is 0.1-0.4 wt%; the content of the defoaming agent in the suspension is 0.02-0.4 wt%.
5. The SCR denitration catalyst suspension of claim 4, wherein the stabilizer comprises ammonia and/or a cellulose ether.
6. The SCR denitration catalyst suspension of claim 4, wherein the corrosion inhibitor comprises one or more of ethanol, propylene glycol, butylene glycol, and diethylamine.
7. The SCR denitration catalyst suspension of claim 4, wherein the suspension has a pH of 9-12.
8. A preparation method of the SCR denitration catalyst suspension liquid as set forth in any one of claims 4 to 7, comprising the steps of:
a) uniformly mixing the nano-scale anatase titanium dioxide, an active component, an active auxiliary agent, a stabilizer, a preservative, a wetting agent, a dispersing agent, a defoaming agent and water to obtain the SCR denitration catalyst suspension.
9. The method according to claim 8, wherein the step a) comprises:
a1) mixing and grinding the nano-scale anatase titanium dioxide, a wetting agent, a dispersing agent, a defoaming agent and part of water to obtain nano-scale anatase titanium dioxide dispersion liquid;
a2) and uniformly mixing the nano-scale anatase titanium dioxide dispersion liquid, the active component, the active auxiliary agent, the stabilizer, the preservative and the balance of water to obtain the SCR denitration catalyst suspension.
10. A catalytic ceramic filter cartridge, comprising a ceramic filter cartridge body and a catalytic component loaded on the ceramic filter cartridge body, wherein the catalytic component is formed by drying the SCR denitration catalyst suspension of any one of claims 4 to 7 coated on the ceramic filter cartridge body at 90 to 110 ℃.
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