CN1935368A - Method for preparing purifying catalyst for reducing cold-start exhaust emission - Google Patents
Method for preparing purifying catalyst for reducing cold-start exhaust emission Download PDFInfo
- Publication number
- CN1935368A CN1935368A CN 200610015587 CN200610015587A CN1935368A CN 1935368 A CN1935368 A CN 1935368A CN 200610015587 CN200610015587 CN 200610015587 CN 200610015587 A CN200610015587 A CN 200610015587A CN 1935368 A CN1935368 A CN 1935368A
- Authority
- CN
- China
- Prior art keywords
- slurries
- content
- mentioned
- catalyst
- powders
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Abstract
The present invention relates to a preparation method of cleaning catalyst capable of reducing cold-starting tail gas discharge. Said cleaning catalyst composition includes the following several portions: acitive aluminium oxide carrier, its content is 20-150 g/L; rare earth composite oxide, its content is 15-200 g/L; filling material, its content is 10-100 g/L; and noble metal, its content is 0.2-2 g/L. The ratio control of noble metal is:Pt/Rh=15:1-2:1; Pd/Rh=10:1-2:1; Pt/Pd/Rh=10:0:1-0:10:1, the La or Ba oxide content in the aluminium oxide is 0-5% and the content control of La Ba and Zr in the catalyst coating layer is 0-15%.
Description
Relating to the field and the present invention relates to the purifying vehicle exhaust technology, is a kind of preparation method who reduces the cold-start exhaust emission cleaning catalyst.
Behind the background technology car engine start, produce carbon monoxide CO, imperfect combustion hydrocarbon HC and nitrogen oxide NO after the oil inflame
X, these are discharged with waste gas the harmful material of the person, and by automobile three-way catalyst bed.Under the effect of automobile three-way catalyst, the major part of these harmful substances can be converted into harmless composition water, carbon dioxide and nitrogen.These catalyst are supported catalyst active component such as noble metal platinum, palladium, rhodium, ruthenium etc. and be used to improve that the auxiliary agent, additive etc. of its catalytic action constitute on such as catalyst carriers such as aluminium oxide, silica, titanium oxide, cerium oxide or zirconia complex rare-earth oxidate containing valuable metal materials normally.
The patent of three-way catalyst also has much at present, various methods have been taked in the improvement of three-way catalyst, the alumina support that is included on the structure and composition on the ceramic honeycomb carrier, uses improve and the selection of additive on, the complex rare-earth oxidate containing valuable metal material that uses and forming is gone up and the optimization etc. that adds various compositions in catalyst, all done very big effort, and also obtained very big progress, the various aspects of performance of three-way catalyst has obtained very big raising.And rely on these progressive, make three-way catalyst be widely used, become auto industry and satisfying important assurance fast-developing under the environmental requirement prerequisite.But in the use of catalyst, still have a lot of problems, comprise that mainly the anti-plumbous performance of anti-sulphur of catalyst is not strong, the high temperature active decay is fast etc.Although people have also proposed a lot of solutions, but still well do not solve at present, have to propose higher requirement from the fuel oil aspect that automobile uses, comprise the strictness control of noxious material content in the fuel oil, the strictness control of rare hydrocarbon content, arene content, alkane content ratio etc. can further reduce the discharging of pollutant in the fuel oil.But along with progressively adding of discharge standard is tight, especially the enforcement of EUROIII Emission Standard even later Europe IV standard is had higher requirement to the cold-start performance of three-way catalyst.That the present invention develops is exactly a kind of preparation method with the cleaning catalyst that reduces the cold-start exhaust emission performance well.
One of summary of the invention purpose of the present invention is alumina source material and the complex rare-earth oxidate containing valuable metal that has better performance by selecting, and improvement Preparation of catalysts technology and preparation method, improve the various aspects of performance of catalyst to a certain extent, especially the cold-start performance of catalyst.Improve material property, improve Preparation of catalysts technology and method, make the aspects such as low temperature ignition performance of catalyst obtain improving significantly, can make the discharging of auto-pollution thing reach EUROIII Emission Standard after using.
The present invention uses the catalyst of doing mixed pre-grinding technics and two process for dispersing of single coating and the two process for dispersing preparations of two coating can satisfy above requirement.
The present invention adopts improved doing to mix pre-grinding technics, this technology can be so that each part of catalyst comprises that cordierite ceramic honeycomb, alumina support, complex rare-earth oxidate containing valuable metal, various additives etc. can reach good coupling, and guarantees the high degree of dispersion of noble metal active component and the surface modification of multiple particle.Simultaneously by using improved alumina supporting material, improved complex rare-earth oxidate containing valuable metal material etc., the resistance to elevated temperatures and the complex rare-earth oxidate containing valuable metal storage oxygen oxygen release ability of alumina support have been improved, help improving the resistance to elevated temperatures of catalyst, reduce the initiation temperature of catalyst, improve the cold-start performance of catalyst, initiation temperature can drop to below 195 ℃, and anti-sintering temperature can be brought up to more than 1000 ℃.
The present invention also carries out preliminary treatment to alumina carrier surface, adjusts the physical and chemical performance of alumina carrier surface, to improve load performance and the dispersiveness and the high-temperature stability of noble metal, prevents that the high temperature of noble metal from assembling and sintering.
In addition, on coated process, improve, invented two process for dispersing of new single coating and the two process for dispersing of two coating.As the Pd-Rh bimetallic catalyst, prepare different catalyst coat materials respectively, promptly contain the Pd coating material and contain the Rh coating material.Through coated Pd coating material earlier on the pretreated honeycomb substrate, pass through coated again Rh coating material after the heat treatment process such as drying and calcining then.Thereby this method can prevent that two kinds of reactive metals of Pd, Rh from directly contacting to be formed the Pd-Rh alloy and causes the loss of activity of such catalysts component, and the poisoning that contacts that reduces Pd and noxious material.The layering of noble metal is coated and add a certain amount of high temperature resistant inert fill material comprise cordierite, mullite, Alpha-alumina etc., the resistance to elevated temperatures and the service life that help improving Europe III catalyst in each coating material.
The present invention is a kind of preparation method who reduces the cold-start exhaust emission cleaning catalyst, it is characterized in that the two process for dispersing of its single coating or two coating comprise the process of being prepared as follows:
The selection of I, raw material:
1) specific surface of alumina support is 140～320m
2/ g, pore volume is greater than 0.35cm
3/ g, average pore size is more than 100 , granularity be D90 below 30 μ m,
2) specific surface of complex rare-earth oxidate containing valuable metal is at 55～320m
2/ g, pore volume is greater than 0.15cm
3/ g, average pore size is more than 110 , granularity be D90 below 30 μ m, wherein the atomic ratio of cerium/zirconium changes in 1/9 to 9/1 scope, one or more in yttrium, lanthanum, praseodymium, the neodymium, content within 0.5%～20% scope,
3) precious metal salt solution comprises nitrate, chloride and the hexahydroxy platinic acid etc. of platinum, palladium, rhodium, ruthenium,
4) salt of the alkali metal of barium, zirconium, calcium, lanthanum, cerium, praseodymium, strontium, yttrium, alkaline-earth metal, rare earth metal or oxide comprise nitrate, acetate, carbonate, sulfate,
5) specific area is at 1～4m
2Between/the g, the inert fill material of granularity below 50 μ m comprises Alpha-alumina, perovskite, calcium oxide, barium monoxide, cordierite, mullite, aluminum magnesium titanate,
6) use impurity content to comprise nitric acid, acetic acid at the acidic materials below 1%,
7) use content of impurities to be no more than 1% alkaline matter and comprise monoethanolamine, ammoniacal liquor, urea, potassium hydroxide,
8) select the cordierite ceramic honeycomb matrix, cell densities is 400 or 600 hole/square inches, wall thickness in 0.1～0.22mm scope,
9) catalyst of the present invention's preparation, the content of active aluminum oxide carrier is 20～150 grams per liters, the use amount of complex rare-earth oxidate containing valuable metal is 15～200 grams per liters, packing material content is 10～100 grams per liters, noble metal is 0.2～2 grams per liter, the proportion control of noble metal is at Pt/Rh=15: 1 to 2: 1, and Pd/Rh=10: 1 to 2: 1, Pt/Pd/Rh=10: 0: 1 to 0: 10: 1.The content of La or Ba oxide is 0～5% in the aluminium oxide, and the content of La, Ba, Zr is controlled in 0～15% in the catalyst coat,
II, grinding and slurrying:
10) add a spot of dispersant with above-mentioned through La and the stable gamma-aluminium oxide carrier of Ba, comprise surfactant or coupling agent, be ground to certain particle then, for D90 within the scope of 3～15 μ m,
11) precious metals pd solution is loaded on the powder after the above-mentioned grinding, be ground to certain particle after mixing with complex rare-earth oxidate containing valuable metal again, granularity be controlled at into D90 within the scope of 5～15 μ m, add certain amount of ammonia water or acetic acid solution then, carried out mixed grinding again 1～5 hour, form wettability mixture of powders A
12) with half of above-mentioned A powder under 120～180 ℃ of temperature dry 1～5 hour, 400～600 ℃ of calcinings 1～5 hour down, form powders A ',
13) with the powders A after wettability mixture of powders A and the calcining ', and an amount of alkali metal, alkaline-earth metal and an amount of inert substance mix the back and add deionized water etc. and make flowable slurries,
14) above-mentioned slurries are transferred to several the liter in the big or small ball grinder, the pH value that adds an amount of acid solution or alkali lye adjustment slurries adds a spot of defoamer within 2～5 scopes, in ball grinder, carry out ball milling then, time is at 4～24 hours, until the particle size D90 of slurries below 10 μ m
15) slurries after taking-up is ground add liquid to solid contents such as acid, alkali or deionized water and reach 20%～45%, form slurries A ",
16) repeat above steps equally, will be through the stable aluminium oxide of La and Ba with after complex rare-earth oxidate containing valuable metal mixes according to a certain percentage, adding a spot of dispersant grinds, then at its area load Rh solution, powder B ' after forming wettability powder B and calcining, again through forming slurries B after above-mentioned each step "
17) above-mentioned powders A and A ' and above-mentioned powder B and B ' are mixed the back according to certain ratio and form powder C, through 13) to 15) each step back form slurries C ",
III, coated and calcining and activating
18) honeycomb substrate is immersed in above-mentioned slurries A " among,
19) after the calcining, it is immersed slurries B " in, repeat 18) step, be prepared into the catalyst A type, this method is the two process for dispersing of two coatings,
20) honeycomb substrate is immersed in above-mentioned slurries C " among; take out after 5～30 seconds; purge with compressed air; put into 100～250 ℃ of dryings of drying box 5～20 hours; reach more than 75% to dehydration rate; put into muffle furnace then and carry out high-temperature calcination, 400～650 ℃ of calcining heats, 3～5 hours time, dry and calcining all is to carry out under air atmosphere, is prepared into catalyst C type, and this method is the two process for dispersing of single coating, above-mentioned catalyst A type and C type can at high temperature carry out reduction activation as required, and reduction is to carry out under reducing atmosphere.
For preparation method of the present invention, it is further characterized in that its single coating or the two process for dispersing preparation process of two coating comprise following process conditions:
The selection of I, raw material:
1) wherein the atomic ratio of cerium/zirconium is in 1/6 to 6/1 scope for complex rare-earth oxidate containing valuable metal, and one or more in yttrium, lanthanum praseodymium, the neodymium, content are in 2%～16% scope,
2) catalyst of the present invention's preparation, the content of active aluminum oxide carrier is 40～130 grams per liters, the use amount of complex rare-earth oxidate containing valuable metal is 18～180 grams per liters, packing material content is 20～80 grams per liters, noble metal is 0.4～1.8 grams per liter, the proportion control of noble metal is at Pt/Rh=13: 1 to 2: 1, and Pd/Rh=8: 1 to 2: 1, Pt/Pd/Rh=8: 0: 1 to 0: 8: 1.The content of La or Ba oxide is 2～4% in the aluminium oxide, and the content of La, Ba, Zr is controlled in 2～12% in the catalyst coat,
II, grinding and slurrying:
3) precious metals pd solution is loaded on the powder after the above-mentioned grinding, be ground to certain particle after mixing with complex rare-earth oxidate containing valuable metal again, add certain amount of ammonia water or acetic acid solution then, carried out mixed grinding again 2～4 hours, form wettability mixture of powders A
4) with half of above-mentioned A powder under 120～180 ℃ of temperature dry 1～5 hour, 450～550 ℃ of calcinings 2～3 hours down, form powders A ',
For preparation method of the present invention, it is further characterized in that its single coating or the two process for dispersing preparation process of two coating also comprise following process conditions:
1) in preparation process, pre-coated a kind of active aluminum oxide carrier on the ceramic honeycomb matrix, or directly carry out the coated of catalyst coat,
2) carried noble metal Pt salt simultaneously among wettability powders A and the A ', A " contain at least a inert material in the slurries and comprise Alpha-alumina, perovskite, cordierite, mullite, aluminum magnesium titanate etc.,
3) slurries B " in do not contain any above-mentioned inert material,
4) slurries C " in contain above-mentioned inert material.
Embodiment
Provide embodiment below.
Embodiment 1, the two process for dispersing of single coating:
1000 gram gama-alumina powder, specific surface 170 meters squared per gram, add organic acid 300 grams, grind 1 hour to granularity D90 less than 15 microns, the palladium nitrate solution that adds 20 gram Pd again, 900 gram (Ce/Zr/La=7: 3: 2) rare earth oxides, specific surface is 65 meters squared per gram, an amount of barium monoxide, zirconia, cerium oxide and an amount of water etc. mix, through ball milling to the certain particle scope, the wettability powders A that forms is divided into 2 parts, and a copy of it is through 150 ℃ of dryings 2 hours, and 400 ℃ of air calcining down became powder B after 2 hours.The rhodium chloride solution that contains 2 gram Rh, appropriate alkaline liquor joins and carries out mixed grinding formation in 2 hours wettability powder C in the 1000 gram gama-alumina powder.Ball milling is carried out in mixing such as above-mentioned powders A, B and C and the above-mentioned gama-alumina powder of 500 grams, 350 gram (Ce/Zr/La=1: 9: 1) rare earth oxides, an amount of acetic acid, appropriate amount of deionized water, 100 gram alpha-alumina powders, 50 gram cordierite powders, 50 gram alumina sols become slurries, cordierite honeycomb matrix with Unit 400 immerses in the pasting then, take out, purge excessive pasting with compressed air, drying is removed free water, calcines 150 minutes for 500 ℃.It is 1.0575 grams per liters that the catalyst of preparation contains noble metal amount, and palladium/rhodium ratio is 10: 1.
Embodiment 2, the two process for dispersing of two coatings:
1100 gram gama-alumina powder, specific surface 170 meters squared per gram, add organic base 300 grams, grind 1 hour to granularity D90 less than 15 microns, the palladium nitrate solution that adds 25 gram Pd again, 850 gram (Ce/Zr/La=7: 3: 2) rare earth oxides, specific surface is 65 meters squared per gram, an amount of barium monoxide, zirconia, cerium oxide and an amount of water etc. mix, through ball milling to the certain particle scope, the wettability powders A that forms is divided into 2 parts, and a copy of it is through 150 ℃ of dryings 2 hours, and 400 ℃ of air calcining down became powder B after 2 hours.The rhodium chloride solution that contains 2.5 gram Rh, appropriate alkaline liquor joins and carries out mixed grinding formation in 2 hours wettability powder C in the 1200 gram gama-alumina powder.Ball milling is carried out in mixing such as above-mentioned powders A, B and the above-mentioned gama-alumina powder of 320 grams, 280 gram (Ce/Zr/La=1: 9: 1) rare earth oxides, an amount of acetic acid, appropriate amount of deionized water, 100 gram alpha-alumina powders, 50 gram cordierite powders, 50 gram alumina sols become slurries A, cordierite honeycomb matrix with Unit 400 immerses in the pasting then, take out, purge excessive pasting with compressed air, drying is removed free water, calcined 150 minutes for 500 ℃, form catalyst precursor A.Ball milling is carried out in mixing such as wettability powder C and above-mentioned 200 gram gama-alumina powder, 220 gram (Ce/Zr/La=1: 9: 1) rare earth oxides, an amount of acetic acid, appropriate amount of deionized water, barium monoxide, zirconia, cerium oxide and 50 gram alumina sols become slurries B, immerse in the pasting with catalyst precursor A then, taking-up purges excessive pasting with compressed air, drying is removed free water, calcines 150 minutes for 500 ℃.It is 1.0575 grams per liters that the catalyst of preparation contains noble metal amount, and palladium/rhodium ratio is 10: 1.
Embodiment 3, the two process for dispersing of single coating:
1200 grams are with 3% cerium, lanthanum, the gama-alumina powder of 2% barium modification, specific surface 180 meters squared per gram, add organic amine 350 grams, grind 1 hour to granularity D90 less than 15 microns, the palladium nitrate solution that adds 20 gram Pd again, 700 gram (Ce/Zr=1: 9) rare earth oxide, specific surface is 110 meters squared per gram, an amount of barium hydroxide, zirconium carbonate, lanthana and an amount of water etc. mix, through ball milling to the certain particle scope, the wettability powders A that forms is divided into 2 parts, and a copy of it is through 150 ℃ of dryings 2 hours, and 400 ℃ of air calcining down became powder B after 2 hours.The rhodium nitrate solution that contains 10 gram Rh, appropriate alkaline liquor joins and carries out mixed grinding formation in 2 hours wettability powder C in the gama-alumina powder of 1000 grams with 3% cerium, lanthanum, 2% barium modification.Ball milling is carried out in mixing such as the gama-alumina powder of above-mentioned powders A, B and C and the above-mentioned modification of 500 grams, 350 gram (Ce/Zr/La=9: 1: 1) rare earth oxides, an amount of acetic acid, appropriate amount of deionized water, 100 gram alpha-alumina powders, 50 gram cordierite powders, 50 gram alumina sols become slurries, cordierite honeycomb matrix with Unit 400 immerses in the pasting then, take out, purge excessive pasting with compressed air, drying is removed free water, calcines 150 minutes for 500 ℃.It is 1.2/ liter that the catalyst of preparation contains noble metal amount, and palladium/rhodium ratio is 2: 1.
Embodiment 4, the two process for dispersing of two coatings:
The gama-alumina powder of 1500 grams, 3% lanthanum, 2% barium modification, specific surface 135 meters squared per gram, add organic acid 400 grams, grind 1 hour to granularity D90 less than 15 microns, add the hexahydroxy platinic acid solution that contains 25 gram Pt earlier, the palladium nitrate solution that adds 25 gram Pd again, and 680 the gram (Ce/Zr/Y=3: 1: 1) complex rare-earth oxidate containing valuable metal, specific surface is 96 meters squared per gram, an amount of barium acetate, zirconium acetate, cerium oxide etc. mix, through ball milling to the certain particle scope, the wettability powders A of formation.The rhodium nitrate solution and the proper quantity of lye that contain 5 gram Rh join and carry out mixed grinding in the gama-alumina powder of 1200 gram 3% lanthanum, 2% barium modifications and formed wettability powder C in 2 hours.Ball milling is carried out in mixing such as the gama-alumina powder of above-mentioned powders A and 320 gram 3% lanthanum, 2% barium modifications, 280 gram (Ce/Zr/La=9: 9: 1) rare earth oxides, an amount of acetic acid, appropriate amount of deionized water, 100 gram alpha-alumina powders, 50 gram cordierite powders, 50 gram alumina sols become slurries A, cordierite honeycomb matrix with Unit 400 immerses in the pasting then, take out, purge excessive pasting with compressed air, drying is removed free water, calcined 150 minutes for 500 ℃, form catalyst precursor A.Ball milling is carried out in mixing such as wettability powder C and above-mentioned 200 gram gama-alumina powder, 220 gram (Ce/Zr/La=3: 1: 1) rare earth oxides, an amount of acetic acid, appropriate amount of deionized water, barium acetate, zirconium acetate, cerium oxide become slurries B, immerse in the pasting with catalyst precursor A then, take out, purge excessive pasting with compressed air, drying is removed free water, calcines 150 minutes for 500 ℃.It is 1.41 grams per liters that the catalyst of preparation contains noble metal amount, and platinum/palladium/rhodium ratio is 5: 5: 2.
Comparative example 1
2000 grams, 3% lanthanum, 1% barium monoxide are stablized the gama-alumina powder, and specific surface 170 meters squared per gram are taken up in order of priority to be impregnated into the H that contains 15 gram Pt
2Pt (OH)
6In the ammonia spirit, contain in the rhodium nitrate solution of 3 gram Rh, contain in the solution of palladium bichloride of 3 gram Pd, above-mentioned powder and barium acetate, zirconium hydroxide, cerium oxide etc. mix, carry out ball milling 3 hours to granularity D90 less than 15 microns, add 80 gram alpha-alumina powders again, 40 gram cordierite powders, 50 gram alumina sols, 1000 gram complex rare-earth oxidate containing valuable metal (60%La2O3,10%CeO2,22%Nd2O3 8%Pr6O11) becomes slurries with ball millings such as water and acetate, and the cordierite honeycomb matrix of Unit 400 immerses in the pasting, take out, purge excessive pasting with compressed air, drying is removed free water, calcines 20 minutes for 500 ℃.It is 1.1 grams per liters that the catalyst of preparation contains noble metal amount, and platinum/rhodium/palladium ratio is 5: 1: 1.
Comparative example 2
Ground floor slurries: 1260 gram gama-alumina powder, specific surface 140 meters squared per gram, dipping contains the palladium chloride solution of 15 gram Pd, dipping contains the rhodium chloride solution of 2.5 gram Rh again, with 950 gram Ce/Zr/La rare earth oxides, specific surface is 75 meters squared per gram, and mixing such as an amount of barium monoxide, zirconia, alpha-alumina powder, Ce/Zr/La rare earth oxide, an amount of acetic acid, appropriate amount of deionized water, cordierite powder, alumina sol are carried out ball milling and become slurries.
Second layer slurries: 1200 grams are with the gama-alumina powder of 3～5% ceriums, lanthanum, 2% barium modification, specific surface 130 meters squared per gram, with the palladium nitrate solution that contains 10 gram Pd, the rhodium nitrate solution that contains 2.5 gram Rh, carry out mixed grinding and form the wettability powder of abundant dispersion, carry out ball milling with mixing such as an amount of acetic acid of Ce/Zr/La/Y rare earth oxide (specific surface is 72 meters squared per gram), deionized waters again and become slurries.
Cordierite honeycomb matrix with Unit 400 immerses in the ground floor slurries then, and compressed air purges excessive pasting, and drying is removed free water, calcines 30 minutes for 500 ℃.Immerse in the second layer slurries, compressed air purges excessive pasting again, and drying is removed free water, calcines 60 minutes for 500 ℃.It is 1.41 grams per liters that the catalyst of preparation contains noble metal amount, and palladium // platinum rhodium ratio is 3: 2: 1.
Initiation temperature evaluation before and after above-mentioned catalyst wears out respectively.Appreciation condition is: 25 * 50 catalyst, air speed 50000h
-1, the consisting of of normal mixture: O
22.5%, H
2O10%, H
20.4 SO～0.8%,
20.02%, HC (C
3H
6: C
3H
81) 0.15%, CO1.5%, NO0.1%=2:.
Aging condition is: calcining is 50 hours in 1050 ℃ of following air.
| Catalyst | Initiation temperature (℃) | |||||
| Fresh catalyst | Aging rear catalyst | |||||
| CO | HC | NO X | CO | HC | NO x | |
| Embodiment 1 | 206 | 225 | 218 | 261 | 298 | 292 |
| Embodiment 2 | 209 | 223 | 216 | 263 | 295 | 297 |
| Embodiment 3 | 201 | 218 | 212 | 260 | 294 | 295 |
| Embodiment 4 | 195 | 202 | 206 | 258 | 290 | 291 |
| Comparative example 1 | 214 | 226 | 233 | 274 | 332 | 305 |
| Comparative example 2 | 208 | 212 | 228 | 270 | 326 | 298 |
Utilize the catalyst of embodiment 1 and embodiment 2 preparations to be applied in cold start after stain thing emission testing under the normal temperature that carries out according to GB18352.3-2005 standard (being equivalent to EUROIII Emission Standard) on the domestic car, the result is respectively THC:0.12g/km and 0.07g/km; CO:0.59g/km and 0.67g/km; NOx:0.01g/km and 0.01g/km.Satisfy the requirement of standard THC:0.2g/km, CO:2.3g/km, NOx:0.15g/km.The catalyst of embodiment 1 preparation is carried out under the low temperature of GB18352.3-2005 standard the emission testing of CO and THC after the cold start, the discharge value of THC and CO is respectively 1.1g/km and 11g/km.Satisfy the requirement of standard THC:1.8g/km and CO:15g/km.
Claims (3)
1, the present invention is a kind of preparation method who reduces the cold-start exhaust emission cleaning catalyst, it is characterized in that the two process for dispersing of its single coating or two coating comprise the process of being prepared as follows:
The selection of I, raw material:
1) specific surface of alumina support is 140～320m
2/ g, pore volume is greater than 0.35cm
3/ g, average pore size is more than 100 , granularity be D90 below 30 μ m,
2) specific surface of complex rare-earth oxidate containing valuable metal is at 55～320m
2/ g, pore volume is greater than 0.15cm
3/ g, average pore size is more than 110 , granularity be D90 below 30 μ m, wherein the atomic ratio of cerium/zirconium changes in 1/9 to 9/1 scope, one or more in yttrium, lanthanum, praseodymium, the neodymium, content within 0.5%～20% scope,
3) precious metal salt solution comprises nitrate, chloride and the hexahydroxy platinic acid etc. of platinum, palladium, rhodium, ruthenium,
4) salt of the alkali metal of barium, zirconium, calcium, lanthanum, cerium, praseodymium, strontium, yttrium, alkaline-earth metal, rare earth metal or oxide comprise nitrate, acetate, carbonate, sulfate,
5) specific area is at 1～4m
2Between/the g, the inert fill material of granularity below 50 μ m comprises Alpha-alumina, perovskite, calcium oxide, barium monoxide, cordierite, mullite, aluminum magnesium titanate,
6) use impurity content to comprise nitric acid, acetic acid at the acidic materials below 1%,
7) use content of impurities to be no more than 1% alkaline matter and comprise monoethanolamine, ammoniacal liquor, urea, potassium hydroxide,
8) select the cordierite ceramic honeycomb matrix, cell densities is 400 or 600 hole/square inches, wall thickness in 0.1～0.22mm scope,
9) catalyst of the present invention's preparation, the content of active aluminum oxide carrier is 20～150 grams per liters, the use amount of complex rare-earth oxidate containing valuable metal is 15～200 grams per liters, packing material content is 10～100 grams per liters, noble metal is 0.2～2 grams per liter, the proportion control of noble metal is at Pt/Rh=15: 1 to 2: 1, and Pd/Rh=10: 1 to 2: 1, Pt/Pd/Rh=10: 0: 1 to 0: 10: 1.The content of La or Ba oxide is 0～5% in the aluminium oxide, and the content of La, Ba, Zr is controlled in 0～15% in the catalyst coat,
II, grinding and slurrying:
10) add a spot of dispersant with above-mentioned through La and the stable gamma-aluminium oxide carrier of Ba, comprise surfactant or coupling agent, be ground to certain particle then, for D90 within the scope of 3～15 μ m,
11) precious metals pd solution is loaded on the powder after the above-mentioned grinding, be ground to certain particle after mixing with complex rare-earth oxidate containing valuable metal again, granularity be controlled at into D90 within the scope of 5～15 μ m, add certain amount of ammonia water or acetic acid solution then, carried out mixed grinding again 1～5 hour, form wettability mixture of powders A
12) with half of above-mentioned A powder under 120～180 ℃ of temperature dry 1～5 hour, 400～600 ℃ of calcinings 1～5 hour down, form powders A ',
13) with the powders A after wettability mixture of powders A and the calcining ', and an amount of alkali metal, alkaline-earth metal and an amount of inert substance mix the back and add deionized water etc. and make flowable slurries,
14) above-mentioned slurries are transferred to several the liter in the big or small ball grinder, the pH value that adds an amount of acid solution or alkali lye adjustment slurries adds a spot of defoamer within 2～5 scopes, in ball grinder, carry out ball milling then, time is at 4～24 hours, until the particle size D90 of slurries below 10 μ m
15) slurries after taking-up is ground add liquid to solid contents such as acid, alkali or deionized water and reach 20%～45%, form slurries A ",
16) repeat above steps equally, will be through the stable aluminium oxide of La and Ba with after complex rare-earth oxidate containing valuable metal mixes according to a certain percentage, adding a spot of dispersant grinds, then at its area load Rh solution, powder B ' after forming wettability powder B and calcining, again through forming slurries B after above-mentioned each step "
17) above-mentioned powders A and A ' and above-mentioned powder B and B ' are mixed the back according to certain ratio and form powder C, through 13) to 15) each step back form slurries C ",
III, coated and calcining and activating
18) honeycomb substrate is immersed in above-mentioned slurries A " among,
19) after the calcining, it is immersed slurries B " in, repeat 18) step, be prepared into the catalyst A type, this method is the two process for dispersing of two coatings,
20) honeycomb substrate is immersed in above-mentioned slurries C " among; take out after 5～30 seconds; purge with compressed air; put into 100～250 ℃ of dryings of drying box 5～20 hours; reach more than 75% to dehydration rate; put into muffle furnace then and carry out high-temperature calcination, 400～650 ℃ of calcining heats, 3～5 hours time, dry and calcining all is to carry out under air atmosphere, is prepared into catalyst C type, and this method is the two process for dispersing of single coating, above-mentioned catalyst A and C can at high temperature carry out reduction activation as required, and reduction is to carry out under reducing atmosphere.
2,, it is characterized in that the two process for dispersing preparation process of its single coating or two coating comprise following process conditions according to the described preparation method of claim 1:
The selection of I, raw material:
1) wherein the atomic ratio of cerium/zirconium is in 1/6 to 6/1 scope for complex rare-earth oxidate containing valuable metal, and one or more in yttrium, lanthanum praseodymium, the neodymium, content are in 2%～16% scope,
2) catalyst of the present invention's preparation, the content of active aluminum oxide carrier is 40～130 grams per liters, the use amount of complex rare-earth oxidate containing valuable metal is 18～180 grams per liters, packing material content is 20～80 grams per liters, noble metal is 0.4～1.8 grams per liter, the proportion control of noble metal is at Pt/Rh=13: 1 to 2: 1, and Pd/Rh=8: 1 to 2: 1, Pt/Pd/Rh=8: 0: 1 to 0: 8: 1.The content of La or Ba oxide is 2～4% in the aluminium oxide, and the content of La, Ba, Zr is controlled in 2～12% in the catalyst coat,
II, grinding and slurrying:
3) precious metals pd solution is loaded on the powder after the above-mentioned grinding, be ground to certain particle after mixing with complex rare-earth oxidate containing valuable metal again, add certain amount of ammonia water or acetic acid solution then, carried out mixed grinding again 2～4 hours, form wettability mixture of powders A
4) with half of above-mentioned A powder under 120～180 ℃ of temperature dry 1～5 hour, 450～550 ℃ were burnt 2～3 hours down, form powders A '.
3,, it is characterized in that the two process for dispersing preparation process of its single coating or two coating comprise following process conditions according to the described preparation method of claim 1:
1) in preparation process, pre-coated a kind of active aluminum oxide carrier on the ceramic honeycomb matrix, or directly carry out the coated of catalyst coat,
2) carried noble metal Pt salt simultaneously among wettability powders A and the A ', A " contain at least a inert material in the slurries and comprise Alpha-alumina, perovskite, cordierite, mullite, aluminum magnesium titanate etc.,
3) slurries B " in do not contain any above-mentioned inert material,
4) slurries C " in contain above-mentioned inert material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100155879A CN100427205C (en) | 2006-09-06 | 2006-09-06 | Method for preparing purifying catalyst for reducing cold-start exhaust emission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100155879A CN100427205C (en) | 2006-09-06 | 2006-09-06 | Method for preparing purifying catalyst for reducing cold-start exhaust emission |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1935368A true CN1935368A (en) | 2007-03-28 |
| CN100427205C CN100427205C (en) | 2008-10-22 |
Family
ID=37953209
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100155879A Expired - Fee Related CN100427205C (en) | 2006-09-06 | 2006-09-06 | Method for preparing purifying catalyst for reducing cold-start exhaust emission |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100427205C (en) |
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102430403A (en) * | 2011-08-29 | 2012-05-02 | 重庆海特汽车排气系统有限公司 | Low-precious metal content high-efficiency ternary catalyst and preparation method thereof |
| CN101249439B (en) * | 2008-03-28 | 2012-09-26 | 无锡威孚环保催化剂有限公司 | Catalyst assembly for processing organic halogenated alkane industrial waste gas and method of preparing the same |
| CN103157470A (en) * | 2013-03-15 | 2013-06-19 | 无锡威孚环保催化剂有限公司 | Three-element catalyst for automobile exhaust |
| CN101687145B (en) * | 2007-04-20 | 2013-06-19 | 大众汽车有限公司 | Exhaust gas after-treatment having reduced rhodium depletion |
| CN103785419A (en) * | 2014-01-27 | 2014-05-14 | 江苏振邦尾气净化有限公司 | Method for preparing automobile three-way catalyst |
| CN103894196A (en) * | 2014-03-14 | 2014-07-02 | 中国石油集团工程设计有限责任公司 | Low-temperature oxidation catalyst for processing claus tail gas and preparation method of catalyst |
| CN103908965A (en) * | 2014-03-14 | 2014-07-09 | 中国石油集团工程设计有限责任公司 | A low-temperature oxidation catalyst used for processing sulfur-containing tail gas and a preparation method thereof |
| CN104136099A (en) * | 2012-03-02 | 2014-11-05 | 赫多特普索化工设备公司 | Method and system for the removal of noxious compounds from engine exhaust gas |
| CN105797721A (en) * | 2016-04-05 | 2016-07-27 | 无锡威孚环保催化剂有限公司 | Method for preparing three-way catalyst high in palladium content |
| CN105828934A (en) * | 2013-12-20 | 2016-08-03 | 喜星触媒株式会社 | Catalytic member for purifying exhaust gases, and washcoat |
| CN104136099B (en) * | 2012-03-02 | 2016-11-30 | 赫多特普索化工设备公司 | For removing the method and system of hazardous compound from engine exhaust |
| CN108883398A (en) * | 2016-04-13 | 2018-11-23 | 丰田自动车株式会社 | Exhaust emission control catalyst, exhaust gas-cleaning method and emission control system |
| CN109794240A (en) * | 2018-12-26 | 2019-05-24 | 中自环保科技股份有限公司 | A kind of bis- coated catalysts of Pd-Rh and preparation method thereof |
| CN110064418A (en) * | 2018-01-23 | 2019-07-30 | 中国石油天然气股份有限公司 | A kind of oxidation state reforming catalyst and preparation method thereof |
| CN111511457A (en) * | 2017-12-19 | 2020-08-07 | 优美科股份公司及两合公司 | Multilayer three-way catalytic converter |
| CN112221494A (en) * | 2020-11-11 | 2021-01-15 | 中自环保科技股份有限公司 | Pt-containing catalyst suitable for gasoline vehicle tail gas purification and preparation method thereof |
| US11623179B2 (en) | 2017-12-19 | 2023-04-11 | Umicore Ag & Co. Kg | Catalytically active particulate filter |
| US11702971B2 (en) | 2017-12-19 | 2023-07-18 | Umicore Ag & Co. Kg | Catalytically active particulate filter |
| CN117085679A (en) * | 2023-10-18 | 2023-11-21 | 昆明贵研催化剂有限责任公司 | Noble metal catalyst for sulfur-containing waste gas treatment and preparation method thereof |
| CN117463364A (en) * | 2023-12-26 | 2024-01-30 | 陕西煤基特种燃料研究院有限公司 | Rh-Ru-based bimetallic load kerosene reforming catalyst and preparation method thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1008885B (en) * | 1986-11-26 | 1990-07-25 | 地质矿产部探矿工程研究所 | The cleaning catalyst for tail gases of automobiles that contains rare earth |
| CN1072107A (en) * | 1991-11-08 | 1993-05-19 | 桂林利凯特(Recat)有限公司 | Rare-earth compound oxide type ternary catalyzer and preparation method |
| JP4464472B2 (en) * | 1997-12-09 | 2010-05-19 | 株式会社日立製作所 | Internal combustion engine exhaust gas purification method and purification device |
| KR20030024085A (en) * | 2001-09-17 | 2003-03-26 | 현대자동차주식회사 | A catalyst for reduction of emitted gases from automobile with lean-burn engine and the manufacturing method thereof |
-
2006
- 2006-09-06 CN CNB2006100155879A patent/CN100427205C/en not_active Expired - Fee Related
Cited By (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101687145B (en) * | 2007-04-20 | 2013-06-19 | 大众汽车有限公司 | Exhaust gas after-treatment having reduced rhodium depletion |
| CN101249439B (en) * | 2008-03-28 | 2012-09-26 | 无锡威孚环保催化剂有限公司 | Catalyst assembly for processing organic halogenated alkane industrial waste gas and method of preparing the same |
| CN102430403B (en) * | 2011-08-29 | 2013-09-11 | 重庆海特汽车排气系统有限公司 | Low-precious metal content high-efficiency ternary catalyst and preparation method thereof |
| CN102430403A (en) * | 2011-08-29 | 2012-05-02 | 重庆海特汽车排气系统有限公司 | Low-precious metal content high-efficiency ternary catalyst and preparation method thereof |
| CN104136099B (en) * | 2012-03-02 | 2016-11-30 | 赫多特普索化工设备公司 | For removing the method and system of hazardous compound from engine exhaust |
| CN104136099A (en) * | 2012-03-02 | 2014-11-05 | 赫多特普索化工设备公司 | Method and system for the removal of noxious compounds from engine exhaust gas |
| CN103157470A (en) * | 2013-03-15 | 2013-06-19 | 无锡威孚环保催化剂有限公司 | Three-element catalyst for automobile exhaust |
| CN103157470B (en) * | 2013-03-15 | 2015-11-04 | 无锡威孚环保催化剂有限公司 | Ternary catalyst for automobile tail gas |
| CN105828934A (en) * | 2013-12-20 | 2016-08-03 | 喜星触媒株式会社 | Catalytic member for purifying exhaust gases, and washcoat |
| CN103785419A (en) * | 2014-01-27 | 2014-05-14 | 江苏振邦尾气净化有限公司 | Method for preparing automobile three-way catalyst |
| CN103785419B (en) * | 2014-01-27 | 2015-11-18 | 江苏几维环境科技有限公司 | A kind of preparation method of automobile three-way catalyst |
| CN103908965A (en) * | 2014-03-14 | 2014-07-09 | 中国石油集团工程设计有限责任公司 | A low-temperature oxidation catalyst used for processing sulfur-containing tail gas and a preparation method thereof |
| CN103908965B (en) * | 2014-03-14 | 2015-11-18 | 中国石油集团工程设计有限责任公司 | A kind of low-temperature oxidation catalyst for the treatment of sulfur-containing tail gas and preparation method thereof |
| CN103894196A (en) * | 2014-03-14 | 2014-07-02 | 中国石油集团工程设计有限责任公司 | Low-temperature oxidation catalyst for processing claus tail gas and preparation method of catalyst |
| CN105797721A (en) * | 2016-04-05 | 2016-07-27 | 无锡威孚环保催化剂有限公司 | Method for preparing three-way catalyst high in palladium content |
| CN108883398B (en) * | 2016-04-13 | 2021-10-12 | 丰田自动车株式会社 | Exhaust gas purification catalyst, exhaust gas purification method, and exhaust gas purification system |
| CN108883398A (en) * | 2016-04-13 | 2018-11-23 | 丰田自动车株式会社 | Exhaust emission control catalyst, exhaust gas-cleaning method and emission control system |
| US11628400B2 (en) | 2017-12-19 | 2023-04-18 | Umicore Ag & Co. Kg | Catalytically active particulate filter |
| CN111511457A (en) * | 2017-12-19 | 2020-08-07 | 优美科股份公司及两合公司 | Multilayer three-way catalytic converter |
| US11623179B2 (en) | 2017-12-19 | 2023-04-11 | Umicore Ag & Co. Kg | Catalytically active particulate filter |
| US11702971B2 (en) | 2017-12-19 | 2023-07-18 | Umicore Ag & Co. Kg | Catalytically active particulate filter |
| CN110064418A (en) * | 2018-01-23 | 2019-07-30 | 中国石油天然气股份有限公司 | A kind of oxidation state reforming catalyst and preparation method thereof |
| CN110064418B (en) * | 2018-01-23 | 2021-11-02 | 中国石油天然气股份有限公司 | Oxidation state reforming catalyst and preparation method thereof |
| CN109794240B (en) * | 2018-12-26 | 2021-12-21 | 中自环保科技股份有限公司 | Pd-Rh double-coating catalyst and preparation method thereof |
| CN109794240A (en) * | 2018-12-26 | 2019-05-24 | 中自环保科技股份有限公司 | A kind of bis- coated catalysts of Pd-Rh and preparation method thereof |
| CN112221494A (en) * | 2020-11-11 | 2021-01-15 | 中自环保科技股份有限公司 | Pt-containing catalyst suitable for gasoline vehicle tail gas purification and preparation method thereof |
| CN112221494B (en) * | 2020-11-11 | 2023-10-20 | 中自环保科技股份有限公司 | Pt-containing catalyst suitable for purifying tail gas of gasoline vehicle and preparation method thereof |
| CN117085679A (en) * | 2023-10-18 | 2023-11-21 | 昆明贵研催化剂有限责任公司 | Noble metal catalyst for sulfur-containing waste gas treatment and preparation method thereof |
| CN117085679B (en) * | 2023-10-18 | 2024-02-02 | 昆明贵研催化剂有限责任公司 | Noble metal catalyst for sulfur-containing waste gas treatment and preparation method thereof |
| CN117463364A (en) * | 2023-12-26 | 2024-01-30 | 陕西煤基特种燃料研究院有限公司 | Rh-Ru-based bimetallic load kerosene reforming catalyst and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100427205C (en) | 2008-10-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100427205C (en) | Method for preparing purifying catalyst for reducing cold-start exhaust emission | |
| CN101385973B (en) | Preparation method of cleaning catalyst capable of increasing low-temperature initiation performance | |
| CN102281946B (en) | Nitrogen oxide storage catalytic converter for use in a motor vehicle in a position near the engine | |
| CN102112211B (en) | Nox storage materials and traps resistant to thermal aging | |
| CN100998941B (en) | Precatalyst and its preparation method | |
| US5990038A (en) | Catalyst for purifying oxygen rich exhaust gas | |
| JP5903205B2 (en) | Exhaust gas purification catalyst | |
| CN101069833B (en) | Hydrocarbon adsorbent, catalyst for treating exhaust gas and method for purifying exhaust gas | |
| EP2452750A1 (en) | Exhaust gas purifying catalyst and method for producing same | |
| CN100544818C (en) | A kind of preparation method of rare earth based tail gas purifying catalyst of motorcycle | |
| CN102405103A (en) | Aging-resistant catalyst article for internal combustion engines | |
| US20180071679A1 (en) | Automotive Catalysts With Palladium Supported In An Alumina-Free Layer | |
| JP7187654B2 (en) | Exhaust gas purification catalyst composition and automobile exhaust gas purification catalyst | |
| EP3466535A1 (en) | Gasoline engine exhaust gas purification three-way catalyst | |
| CN113042045B (en) | Exhaust gas purifying catalyst | |
| EP2029261B1 (en) | Catalyst for purification of exhaust gas | |
| CN103097021B (en) | NOx storage catalyst with reduced Rh loading | |
| US11686231B2 (en) | LNT layered catalyst for lean burn gasoline engine and exhaust gas purification apparatus using the same | |
| CN1803263A (en) | Three-efficiency catalyst for purifying automobile end gas and its preparation method | |
| CN1311903C (en) | Method for preparing rare earth base high-performance three-effect catalyst | |
| WO2019167515A1 (en) | Exhaust purification three-way catalyst and manufacturing method therefor, and exhaust purification monolithic catalyst | |
| JPH1085604A (en) | Catalyst for cleaning of exhaust gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20081022 Termination date: 20150906 |
|
| EXPY | Termination of patent right or utility model |