CN104941677A - High-stability coating material and preparation method of catalyst for purification of motor vehicle tail gas - Google Patents
High-stability coating material and preparation method of catalyst for purification of motor vehicle tail gas Download PDFInfo
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- CN104941677A CN104941677A CN201410781095.5A CN201410781095A CN104941677A CN 104941677 A CN104941677 A CN 104941677A CN 201410781095 A CN201410781095 A CN 201410781095A CN 104941677 A CN104941677 A CN 104941677A
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Abstract
The invention discloses a high-stability coating material composition, a loading technique of active ingredient Pd and a preparation method of coating slurry. Besides a catalytic active ingredient (Pd), a rare earth catalyst promoter, an oxygen-storage material and activated aluminum oxide, the coating material composition is characterized by further comprising silicon carbide and tungsten oxide and taking a synergistic effect together with rare earth cerium oxide and lanthanum oxide; Pd is immobilized on a La modified coating material such as aluminum oxide and oxygen-storage material by virtue of an impregnating-precipitating method in advance; by replacing a conventional Ce/Zr oxide solid solution with a high-performance Ce/Zr/Pr oxide solid solution oxygen-storage material and by improving the preparation process and parameter of slurry, the slurry is remarkably improved in terms of properties such as fluidity, nano particle distribution uniformity and adhesion. After being aged at 1000 DEG C, the prepared catalyst for purification of motor vehicle tail gas still has excellent catalytic activity and high-temperature stability; in addition, the process is simple and the cost is low; therefore, the catalyst is applicable to industrial production.
Description
Technical field
The present invention relates to a kind of integral automobile exhaust purification catalyst coating composition and preparation method of high-temperature stable, it is characterized in that when the coating paste of Kaolinite Preparation of Catalyst, with the addition of carborundum and tungsten oxide material, adopt high performance cerium zirconium praseodymium oxide solid solution to replace conventional CeO2-ZrO2 solid solution simultaneously, thus significantly improve the heat endurance of monoblock type three-way catalyst, still there is excellent catalytic activity and stability after high temperature (as 1000 DEG C) is aging.
Background technology
In recent years, along with the fast development of urban construction and the quick increase of automobile pollution, the pollution of vehicle exhaust to urban atmosphere is also on the rise.Three-way catalyst is widely used in the control of vehicle exhaust to reduce the discharge of CO, HC and NOx.In use, three-way catalyst can cause the reduction of catalyst activity under being chronically exposed to thermal environment.Al in coating material
2o
3can undergo phase transition with micropore sintered, the specific area of catalyst sharply declines, thus exacerbates growing up and sintering of noble metal active component, auxiliary agent cerium oxide and cerium zirconium hydrogen-storing material crystal grain, causes catalyst performance to decline.In recent years, in order to make the catalyst when engine just starts just can show good activity immediately, the installation of catalyst-assembly from engine more and more close to, this just requires that catalyst has better heat endurance.The three-effect catalyst for purifying tail gas of car of research and development high-temperature stable becomes focus in recent years.
Patent CN100396363C reports a kind of three-way catalyst being carrier with alumina load cerium zirconium sosoloid, and active component is PdO, and cerium zirconium sosoloid accounts for 10 ~ 50wt% of catalyst quality, and the negative tailoring of Pd accounts for 0.5 ~ 1.5% of catalyst quality.Its preparation method is preparation cerium zirconium soluble-salt and the mixed solution of stubborn rubber acid, is impregnated into altogether on alumina powder, and step obtains the cerium zirconium compound oxide carrier of alumina load through drying, after roasting etc.PdO/CeZrO is obtained through steps such as oven dry, roasting, reduction after dipping precious metal solution
x/ Al
2o
3three-way catalyst.
Patent CN101773830A reports a kind of preparation method of the high stability catalyst for catalytic cleaning of car tail gas, it is characterized in that prepared high-temperature stable material is the composite oxide solid solution that noble metal, cerium oxide, zirconia and auxiliary agent are formed.Compare the three-way catalyst that traditional infusion process obtains, this invention prepared by catalyst can ensure metal oxide containing precious metals stable existence under the high temperature conditions, there is good catalytic effect, the standard of exhaust emissions can be reached.
The one that reports patent CN101695661B can improve hydrocarbon compound in exhaust of lean-burn automotive (HC) treatment effect, also has three-way catalyst of purified treatment effect and preparation method thereof to carbon monoxide (CO) and nitrogen oxide (NO) simultaneously.When catalyst preparing, water-soluble cerium salt, zirconates and barium salt are formed water solution mixture, is added drop-wise in the aqueous solution containing precipitating reagent.The solids formed obtains cerium zirconium ba oxide after drying rear grinding, roasting, then floods copper salt solution, obtains catalyst after drying and roasting.
Patent CN 102728383 B reports a kind of preparation method of integral automobile exhaust purification catalyst of high-temperature stable, catalyst activity component Pd, co-catalyst, hydrogen-storing material and activated alumina etc. are made catalyst coat slurry, then slurry is coated on cordierite nest shape ceramic monolith, it is characterized in that with the addition of appropriate complexed surfactant in coating paste preparation process, simultaneously first by pre-soaked for Pd on the aluminium oxide of La modification.The monoblock type three-way catalyst of preparation still has excellent activity and stability after high temperature (as 1000 DEG C) is aging.
Along with improving constantly of automobile exhaust emission standard, also more and more higher to the requirement of triple effect cleaning catalyst, wherein heat endurance is a very important performance, exploitation have practicality, the technology of preparing preparing the three-way catalyst of high-temperature stable of simple possible to be to meet the requirement more and more higher to three-way catalyst performance.
Summary of the invention
The object of the invention is to provide a kind of composition and the preparation method that prepare the integral automobile exhaust purification catalyst of high-temperature stable, its core technology to improve the composition of catalyst coat material, give full play to carborundum and the effect of tungsten oxide in raising catalyst heat endurance and high temperature active, by the dipping-precipitation method, Pd is fixed on the coating material such as aluminium oxide and cerium zirconium praseodymium oxide solid-solution powder of La modification in advance, adopt high performance cerium zirconium praseodymium oxide solid solution replace conventional CeO2-ZrO2 solid solution and improve the fixed form of catalyst activity component Pd on coating material simultaneously, relate to composition and the preparation method of the integral automobile exhaust purification catalyst slurry devising a kind of high-temperature stable disclosed by the invention for this reason, thus significantly improve the heat endurance of monoblock type three-way catalyst.The above-mentioned catalyst adopting coating material of the present invention and preparation method to prepare still has excellent catalytic activity and stability after high temperature (as 1000 DEG C) is aging.
Catalyst of the present invention is made up of cordierite honeycomb ceramics carrier and coating, wherein coating quality is 30 ~ 50% of carrier, the composition of coating and mass percent are: the load capacity of Pd accounts for 0.5 ~ 1.5 % of integral catalyzer coating quality, cerium zirconium praseodymium composite oxide solid solution accounts for 10 ~ 30% of coating quality, carborundum and tungsten oxide account for 8 ~ 12% of coating quality, and the mass ratio controlling carborundum and tungsten oxide is 1 ~ 5; Carborundum and tungsten oxide and rare earth oxide act synergistically in the coating, and described rare earth oxide is the mixture of ceria and lanthanum sesquioxide, accounts for 2 ~ 8% of coating quality; All the other are aluminium oxide and the rare earth oxide of La modification.
The method of the above-mentioned catalyst of preparation disclosed by the invention, is characterized in that mainly comprising the following steps:
Configuration Pd (NO
3)
2, cerous nitrate, ammonium tungstate and surfactant the aqueous solution, after stirring 10 ~ 30 minutes at 40 ~ 60 DEG C; Surfactant is made up of Tween-80, this dish-20, polyethylene glycol-200, and the concentration in coating paste is 0.01 ~ 0.005g/ L;
Join in the above-mentioned aqueous solution by the aluminium oxide of La modification and cerium zirconium praseodymium oxide solid-solution powder, stir after 1 hour, the pH regulating slurry with ammoniacal liquor is 10 ~ 11, stirred at ambient temperature 2 ~ 8 hours;
Under agitation join in above-mentioned slurry by carborundum, lanthanum nitrate and boehmite powder, the pH regulating slurry with nitric acid is 7 ~ 8, stirs after 1 ~ 2 hour, then regulates the pH of slurry to be 3 ~ 4 with nitric acid, continues stirring 1 ~ 2 hour obtained coating paste;
Under vacuum, slip is evenly coated on the cellular-shaped ceramic monolith of cordierite, through 60 DEG C of dryings 5 ~ 20 hours and 120 DEG C of dryings after 5 ~ 20 hours, roasting 2 ~ 4 hours in the air of 400 ~ 650 DEG C.
Compared with the preparation method of existing three-way catalyst, preparation method of the present invention has following features: in the slurry preparation process of catalyst, add ammonium tungstate and carborundum, act synergistically with rare earth oxide (cerium oxide and lanthana), give full play to tungsten oxide and the effect of carborundum in raising coating high-temp stability; By the dipping-precipitation method Pd is fixed in advance on the coating materials such as the aluminium oxide of La modification and cerium zirconium praseodymium oxide solid-solution powder, makes the Pd more all even load that distributes more firm; Adopt high performance cerium zirconium praseodymium oxide solid solution to replace conventional CeO2-ZrO2 solid solution, what further increase catalyst stores oxygen performance; Improve preparation process and the parameter of slurry, the performances such as the uniformity that the mobility of slurry, nano particle are distributed and adhesion have all had improvement, thus improve the resistance to elevated temperatures of the catalyst of preparation.Method for preparing catalyst technique of the present invention is simple, with low cost, is very suitable for applying in suitability for industrialized production.
Detailed description of the invention
In order to understand the present invention better, illustrate content of the present invention further below in conjunction with example.
[embodiment 1]
By Pd (NO
3)
2the aqueous solution (Pd accounts for 0.8% of dry coating mass), cerous nitrate and ammonium tungstate (mixed oxide accounts for 5% of dry coating mass) join in 120g deionized water, under agitation be heated to 50 DEG C, stir after 10 minutes and add 3g (mixture of Macrogol 200, Tween 80 and this dish 20) surfactant, continue stirring after 10 minutes, add 50g La-aluminium oxide and 5g carborundum, continue stirring 6 hours;
Add 5g boehmite, 3g lanthanum nitrate and 10g cerium zirconium praseodymium oxide solid solution under stirring, add 5mL red fuming nitric acid (RFNA), regulate pH to 3 ~ 4, continue stirring 1 hour; Under vacuo slurry is coated to (be of a size of 15mm × 30mm, volume is 5.3mL) on cordierite honeycomb ceramic carrier; 60 DEG C of dryings 12 hours, 120 DEG C of dryings 12 hours, fuse 3 hours, obtained fresh catalyst 1# in 500 DEG C of air;
[embodiment 2]
Prepare in the process of slurry in embodiment 1, ammonium tungstate is changed to lanthanum nitrate (percentage by weight of oxide and the identical of tungsten oxide), other conditions, with embodiment 1, obtain fresh catalyst 2#.
[embodiment 3]
Prepare in the process of slurry in embodiment 1, do not add carborundum, cerium zirconium praseodymium oxide solid solution is changed to conventional CeO2-ZrO2 solid solution, other conditions, with embodiment 1, obtain fresh catalyst 3#.
[embodiment 4]
Prepare in the process of slurry in embodiment 1, the amount of carborundum is increased to 10g, other conditions, with embodiment 1, obtain fresh catalyst 4#.
[embodiment 5]
Prepare in the process of slurry in embodiment 1, tungsten oxide is changed to nickel nitrate and manganese nitrate (percentage by weight of oxide and the identical of tungsten oxide), does not add carborundum, other conditions, with embodiment 1, obtain fresh catalyst 5#.
[embodiment 6]
By Pd (NO
3)
2the aqueous solution (Pd accounts for 0.8% of dry coating mass), cerous nitrate and ammonium tungstate (mixed oxide accounts for 5% of dry coating mass) join in 120g deionized water, under agitation be heated to 50 DEG C, stir after 10 minutes and add 3g (mixture of Macrogol 200, Tween 80 and this dish 20) surfactant, continue stirring after 10 minutes, add 50g La-aluminium oxide and 10g cerium zirconium praseodymium oxide solid solution, stir after 1 hour, the pH regulating slurry with ammoniacal liquor is 10 ~ 11, stirs 4 hours;
Under agitation add 5g boehmite, 3g lanthanum nitrate and 5g carborundum, the pH regulating slurry with red fuming nitric acid (RFNA) is 7 ~ 8, stirs after 1 hour, then regulates the pH of slurry to 3 ~ 4 with red fuming nitric acid (RFNA), continues stirring 1 hour; Under vacuo slurry is coated to (be of a size of 15mm × 30mm, volume is 5.3mL) on cordierite honeycomb ceramic carrier; 60 DEG C of dryings 12 hours, 120 DEG C of dryings 12 hours, fuse 3 hours, obtained fresh catalyst 6# in 500 DEG C of air;
The integral catalyzer more than prepared obtains aging catalyst through 1000 DEG C of roastings after 4 ~ 8 hours, they carry out in the microreactor of fixed bed continuous-flow the three-way catalytic activity of purifying vehicle exhaust, the reaction gas composition of simulated automotive tail gas is in table 1, and gas space velocity is 2 × 10
4h
1, the concentration of each component of reaction gas adopts automobile exhaust analyzer (Siemens E-BOX) to realize on-line analysis, the activity T to each catalytic reaction of each catalyst
50(reaction temperature when conversion ratio is 50 %) represents, catalytic activity data is in table 2.
Table 1 simulation reaction gas forms
Activity (the T of table 2 catalyst
50) and action pane (empty so than λ)
Described content be only the present invention conceive under basic explanation, and according to technical scheme of the present invention do any etc.
Effect conversion, all should belong to protection scope of the present invention.
Claims (3)
1. for a preparation method for the integral catalyzer of purifying vehicle exhaust, described catalyst is made up of cordierite honeycomb ceramics carrier and coating, and wherein coating quality is 30 ~ 50% of carrier; The composition of coating and mass percent are: the load capacity of Pd accounts for 0.5 ~ 1.5% of integral catalyzer coating quality, cerium zirconium praseodymium oxide solid solution accounts for 10 ~ 30% of coating quality, carborundum and tungsten oxide account for 8 ~ 12% of coating quality, and all the other are aluminium oxide and the rare earth oxide of La modification; It is characterized in that the catalyst adopting preparation method of the present invention to prepare contains carborundum and tungsten oxide, by the dipping-precipitation method Pd is fixed in advance on the coating materials such as the aluminium oxide of La modification and cerium zirconium praseodymium oxide solid-solution powder, still there is excellent catalytic activity and stability after high temperature ageing.
2. for the catalyst coat described in claims 1, it is characterized in that with the addition of carborundum and tungsten oxide in the coating, act synergistically in the coating with rare earth oxide, the mass ratio of carborundum and tungsten oxide is 1 ~ 5; Described rare earth oxide is the mixture of ceria and lanthanum sesquioxide, accounts for 2 ~ 8% of coating quality.
3., for the preparation method described in claims 1, it is characterized in that comprising the following steps:
(1) Pd (NO is configured
3)
2, cerous nitrate, ammonium tungstate and surfactant the aqueous solution, after stirring 10 ~ 30 minutes at 40 ~ 60 DEG C, the aluminium oxide of La modification and cerium zirconium praseodymium oxide solid-solution powder are joined in the above-mentioned aqueous solution, stirs after 1 ~ 2 hour, the pH regulating slurry with ammoniacal liquor is 10 ~ 11, stirs 2 ~ 8 hours;
(2) under agitation join in above-mentioned slurry by carborundum, lanthanum nitrate and boehmite powder, the pH regulating slurry with nitric acid is 7 ~ 8, stirs after 1 ~ 2 hour, then regulates the pH of slurry to be 3 ~ 4 with nitric acid, continues stirring 1 ~ 2 hour obtained coating paste;
(3) under vacuum, slip is evenly coated on the cellular-shaped ceramic monolith of cordierite, through 60 DEG C of dryings 5 ~ 20 hours and 120 DEG C of dryings after 5 ~ 20 hours, roasting 2 ~ 4 hours in the air of 400 ~ 650 DEG C.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109012665A (en) * | 2018-08-16 | 2018-12-18 | 无锡威孚环保催化剂有限公司 | A kind of double coating three-way catalysts and preparation method thereof |
| CN111974390A (en) * | 2020-08-21 | 2020-11-24 | 包头稀土研究院 | Catalyst for tail gas of diesel vehicle, preparation process and application |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100998941A (en) * | 2007-01-04 | 2007-07-18 | 华东理工大学 | Precatalyst and its preparation method |
| CN101433846A (en) * | 2008-12-17 | 2009-05-20 | 天津大学 | Cerium-based composite oxides supported precious metal three-effect catalyst and preparation method thereof |
| CN101773830A (en) * | 2010-02-25 | 2010-07-14 | 华东理工大学 | High-temperature stability catalyst used for three-effect catalysis |
| CN102728383A (en) * | 2012-02-22 | 2012-10-17 | 华东理工大学 | Preparation method of high temperature stable monolithic catalyst for purifying tail gas of automobile |
| CN103240083A (en) * | 2013-05-16 | 2013-08-14 | 浙江师范大学 | Monolithic Pd catalyst for purifying industrial organic waste gas and preparation method thereof |
| CN104174412A (en) * | 2014-08-28 | 2014-12-03 | 金华欧仑催化科技有限公司 | Three-way catalyst for automotive exhaust purification and preparation method thereof |
-
2014
- 2014-12-18 CN CN201410781095.5A patent/CN104941677B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100998941A (en) * | 2007-01-04 | 2007-07-18 | 华东理工大学 | Precatalyst and its preparation method |
| CN101433846A (en) * | 2008-12-17 | 2009-05-20 | 天津大学 | Cerium-based composite oxides supported precious metal three-effect catalyst and preparation method thereof |
| CN101773830A (en) * | 2010-02-25 | 2010-07-14 | 华东理工大学 | High-temperature stability catalyst used for three-effect catalysis |
| CN102728383A (en) * | 2012-02-22 | 2012-10-17 | 华东理工大学 | Preparation method of high temperature stable monolithic catalyst for purifying tail gas of automobile |
| CN103240083A (en) * | 2013-05-16 | 2013-08-14 | 浙江师范大学 | Monolithic Pd catalyst for purifying industrial organic waste gas and preparation method thereof |
| CN104174412A (en) * | 2014-08-28 | 2014-12-03 | 金华欧仑催化科技有限公司 | Three-way catalyst for automotive exhaust purification and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 李烨等: "添加WO3提高铈锆固溶体的氨选择性催化还原NOx反应活性", 《催化学报》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109012665A (en) * | 2018-08-16 | 2018-12-18 | 无锡威孚环保催化剂有限公司 | A kind of double coating three-way catalysts and preparation method thereof |
| CN109012665B (en) * | 2018-08-16 | 2021-04-06 | 无锡威孚环保催化剂有限公司 | Double-coating three-way catalyst and preparation method thereof |
| CN111974390A (en) * | 2020-08-21 | 2020-11-24 | 包头稀土研究院 | Catalyst for tail gas of diesel vehicle, preparation process and application |
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| CN104941677B (en) | 2019-05-31 |
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