CN102513165A - Efficient method for coating tail gas clean-up three-way catalyst - Google Patents
Efficient method for coating tail gas clean-up three-way catalyst Download PDFInfo
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- CN102513165A CN102513165A CN2011104174244A CN201110417424A CN102513165A CN 102513165 A CN102513165 A CN 102513165A CN 2011104174244 A CN2011104174244 A CN 2011104174244A CN 201110417424 A CN201110417424 A CN 201110417424A CN 102513165 A CN102513165 A CN 102513165A
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Abstract
The invention discloses an efficient method for coating tail gas clean-up three-way catalyst, which specifically comprises the steps of two-segment twice coating, two-segment twice overlapped coating and the-segment three-times coating. By adopting the coating method, the water washed slurry formed of the catalysis elements, assistants and a number of oxides, which take different actions, is coated on a same carrier in a segmentation and layering manner, so that the same catalyst carrier takes the action of a front-stage catalyst and a rear-stage catalyst, and the tail gas control function is optimized, and the parts system installation space pressure is relieved. The coating method simplifies system design, improves production efficiency, and greatly reduces cost.
Description
[technical field]
The present invention relates to a kind of cleaning catalyst for tail gases of automobiles coating method, relate in particular to a kind of efficient tail-gas purifying three-way catalyst staged and layered and apply new method.
[background technology]
Along with the quick increase of whole world automobile pollution, vehicle exhaust has become the primary pollution source of urban air pollution.According to the interrelated data statistics, the carbon monoxide in the urban air more than 90%, the oxynitrides more than the hydrocarbon more than 60% and 30% is from motor vehicle exhaust emission.In order to control the pollution of vehicle exhaust, except that formulating strict discharge index, also should strengthen research and development to purifying vehicle exhaust to atmosphere.Conventional approach to vehicle exhaust control employing three-way catalyst is on pottery or metallic carrier, evenly to apply by certain catalysagen material than the row mixing both at home and abroad; Comprise aluminium oxide; Zirconia, cerium oxide (or cerium zirconium sosoloid powder) and other metal oxides, rare earth oxide and some other additives.
Over nearly more than 20 years because various countries control increasingly stringent to exhaust emissions; Add that the automobile market price competition is fierce day by day; The catalyst traditional fabrication can not meet the demands with even coated technique, the new coating technology that different coating adopts different raw material and precious metal catalyst element not of the same race therefore occurred.Be illustrated in figure 1 as the coating method of present standard of comparison; Coating can have two layers; But also three to four layers of as many as (referring to patent document 1, patent document 2 and patent document 3); Be characterized in each coating catalysis characteristics along carrier shaft to the even same sex, radially catalysis characteristics is different, this be because between layer and the layer catalysagen material that adopted with fill a prescription different.But its each layer all uses same coating material to apply; Coating covers whole carrier each minim channel surface from air flow inlet to outlet; Cover the appearance of internal layer than cladding material; By that analogy, making the single clarifier carrier that applies like this is single to outlet to the tail gas control action from import, can't play the double action of forward and backward level catalyst.
Control requires increasingly stringent to vehicle exhaust along with various countries; Must adopt different catalysis strategy, formula technique and catalysis material to the various loads of engine, rotating speed, cooling and heating machine state; Therefore the different multistage antigravity system (referring to patent document 4) of function has appearred; Be about to two or three different catalyst carriers and use together, be i.e. two-stage or multistage antigravity system.But because modern vehicle and engine design technical development, vehicle is more and more compacter, engine power is increasing, and the parts installing space is limited, and multistage catalyst is the mounting process relative complex not only, and its space that occupies is also bigger.
The prior art file
Patent document
Patent document 1: Chinese patent notification number CN102083530A; At on 06 01st, 2011 day for announcing; Name is called and ' is used to purify the honeycomb structure type catalyst of automobile institute discharging waste gas; Its preparation method and use the method for this catalyst purifying exhaust air ' in a kind of honeycomb type structure catalyst is disclosed, the carrier that wherein is made up of the honeycomb type structure is coated with two-layer above carbon monoxide-olefin polymeric, is used for the contained carbon monoxide of purifying exhaust air, hydrocarbon and nitrogen oxide.
Patent document 2: Chinese patent notification number CN102008958A; At on 04 13rd, 2011 day for announcing; Name is called and discloses a kind of three-way catalyst and preparation method who purifies tail-gas from gasoline automobiles in ' a kind of three-way catalyst that purifies tail-gas from gasoline automobiles and preparation method thereof '; The catalytic active layer of this three-way catalyst is a double-decker, and the internal layer catalytic active layer is one or more oxides in activated alumina supported rare earth metal, alkaline-earth metal, transition metal, the noble metal; Outer catalytic active layer is activated alumina supported rare earth metal, alkaline-earth metal, one or more oxides of noble metal.
Patent document 3: Chinese patent notification number CN102131582A; At on 07 20th, 2011 day for announcing; Name is called in ' exhaust gas purifying catalyst, the waste gas purification apparatus that uses it and exhaust gas purifying method ' and discloses a kind of exhaust gas purifying catalyst; It is characterized in that the carbon monoxide-olefin polymeric that will be used for the contained hydrocarbon of purifying exhaust air (HC), carbon monoxide (CO) and nitrogen oxide (NOx) is with the two-layer honeycomb type structure that is coated at least up and down as follows.
Patent document 4: Chinese patent notification number CN102083531A; At on 06 01st, 2011 day for announcing; Name is called in ' catalyst-assembly of purifying exhaust air and the method for purifying exhaust air ' and discloses a kind of catalyst-assembly that is used for purifying exhaust air; It is characterized in that the honeycomb structure type catalyst (Y) that is arranged in the honeycomb structure type catalyst (X) of upstream side and is arranged in the downstream all comprises by at least a inorganic oxide support material that does not contain Rh component and supporting Pt component or Pd component basically, contains the carbon monoxide-olefin polymeric that cerium oxide and alkaline earth metal component constitute in all lower floors.
According to the coating method of above-mentioned patent document 1-3, its common feature be each coating catalysis characteristics along carrier shaft to the even same sex, be single to outlet to the tail gas control action from import.
According to the coating method of above-mentioned patent document 4, characteristics are to be coated on two carriers, reality be exactly before and after the level catalyst, its shortcoming is that system design, processing, encapsulation are complicated, production efficiency is lower and production cost is higher.
[summary of the invention]
The present invention has overcome the deficiency of prior art, provides a kind of efficient tail-gas purifying three-way catalyst staged and layered to apply new method.
The technical scheme that the present invention adopts is: a kind of efficient tail-gas purifying three-way catalyst coating method; Be to export from the tail gas import to tail gas to the single-piece catalyst carrier to carry out at least two segmentations; Adopt the catalyst pulp of different formulations to apply to different segmentations, the clarifier carrier surface of same segmentation is carried out once above catalyst material apply.
Above-described efficient tail-gas purifying three-way catalyst coating method, first coating covers the half carrier of tail gas air-flow upstream extremity, and second coating covers the half carrier of airflow downstream.
Above-described efficient tail-gas purifying three-way catalyst coating method, the 3rd coating covers the big half carrier of tail gas air-flow upstream extremity, and the 4th coating covers the big half carrier in downstream, and interlude can have the overlapping area of coverage.
Above-described efficient tail-gas purifying three-way catalyst coating method; The coating method of the 5th coating and the 6th coating is similar with two sections twice coatings; The 5th coating and the 6th coating applied and roasting after carry out the coating of the 7th coating again, the 7th coating covers the big half carrier of upstream extremity or downstream.
Above-described efficient tail-gas purifying three-way catalyst coating method after said clarifier carrier surface to same layering carries out each catalyst material coating, carries out roasting to said catalyst carrier, and total roasting number of times is twice before the finished product.
Above-described efficient tail-gas purifying three-way catalyst staged and layered coating method; The length of the described overlapping area of coverage can require decision according to tail gas control; Also can confirm through the engine exhaust emission test; General interlude overlay region length is no more than 33% of carrier lengths, leans on an end overlay region length to be no more than carrier lengths 66%.
Above-described efficient tail-gas purifying three-way catalyst staged and layered coating method, the number of plies of described coating is the 1-4 layer, the coating load capacity is every liter of 140-200 gram.
Above-described efficient tail-gas purifying three-way catalyst staged and layered coating method, described sintering temperature is a 500-600 ℃ of degree.
The present invention is owing to adopted such scheme; Have the following advantages with respect to prior art: the washing slurry that will play catalytic elements, auxiliary agent and the formation of multiple oxide of different effects; Identical carrier is carried out staged and layered to apply; Can reach same catalyst carrier and play front and back level catalyst action, optimize tail gas control function, not only can alleviate the pressure of pts system installing space, also can the simplification system design, enhance productivity, greatly reduce cost; Be better than traditional product in catalyst fabrication and processing, carrier package processing, parts globality, the adjustment of catalyst control strategy on optimizing.
[description of drawings]
Fig. 1 is the coating structure sketch map of traditional standard.
Fig. 2 is two sections twice coating structure sketch mapes of the present invention.
Fig. 3 is two sections twice overlapping coating structure sketch mapes of the present invention.
Fig. 4 is three sections three coating structure sketch mapes of the present invention.
[specific embodiment]
Below in conjunction with accompanying drawing the specific embodiment of the invention is done further detailed explanation.
Embodiment 1-3 explanation is the basis with existing advanced catalyst formulation technology, and the washing slurry with the catalytic elements that plays different effects, auxiliary agent and multiple oxide form carries out three kinds of methods that staged and layered applies to identical carrier.
Embodiment 1
Be illustrated in figure 3 as two sections twice coating structure sketch mapes, first coating 1 covers the half carrier of tail gas air-flow upstream extremity, and second coating 2 covers the half carrier of airflow downstream.Promptly carry out the coating of second coating 2 after first coating 1 has been coated with, carrying out Celsius temperature then is the roasting of 500-600 degree, in order to meet the requirements of the coating load capacity, repeats the coating and the roasting moulding of first coating 1 and second coating 2 again.The coated carrier Upstream section is all different with catalysagen material, catalytic elements concentration and prescription that the tract coating is adopted, and this needs to adjust according to the discharging characteristics of concrete vehicle.So just can obtain carrier shaft to (airflow direction) diverse catalysis characteristics, increase the scope of design and the flexibility of modern catalysts greatly.
Embodiment 2
Be illustrated in figure 4 as two sections twice overlapping coating structure sketch mapes; The 3rd coating 3 covers the big half carrier of tail gas air-flow upstream extremity; The big half carrier in the 4th coating 4 covering downstream, so interlude can have the overlapping area of coverage, concrete overlay segment length can require decision according to tail gas control.Like this, along carrier shaft in fact just having formed three kinds of different coatings catalysis characteristicses.
Embodiment 3
Be illustrated in figure 5 as three sections three coating structure sketch mapes; The coating method of the 5th coating 5 and the 6th coating 6 is similar with embodiment 1; The 5th coating 5 and the 6th coating 6 applied and roasting after carry out the coating of the 7th coating 7 again, the 7th coating 7 covers the big half carrier of upstream extremities or downstream.Like this; The actual catalyst formulation coating material that can use three kinds of different catalysis strategies; Can make up the function optimization of oxidation in the three-way catalyst, reduction; Also can the catalyst that be used for specific purposes (as the NOxadsorber that is used for gasoline direct igniter motor GDI is technological) be introduced the Catalyst Design of single carrier simultaneously, bring huge flexibility to design.
The foregoing description only is with helping to understand instance of the present invention, and the invention is not restricted to this instance.Belong to technical scope modification of the present invention and variation all in the scope of the invention.
As shown in Figure 5; The 4th coating 4 materials are to the prescription of hydrocarbon (HC) emission control under the engine cold-start operating mode; Adopt the higher precious metal palladium of load capacity as main catalyst elements, coating delivery material is activated alumina, cerium zirconium compound solid solution body, nickel oxide etc.; The 6th coating 6 materials adopt the three-element catalytic agent prescription of standard; Coating material is lower palladium rhodium (proportioning is 10: 1) the precious metal catalyst element of modified aluminas, cerium zirconium compound solid solution body, micro-nickel, barium, yttrium oxide and load capacity, and the cerium oxide of higher percent is as the hydrogen-storing material in the coating; The 7th coating 7 is an assists coating, is the precious metal catalyst element with the rhodium that hangs down load capacity, strengthens the reduction process of nitrogen oxide.
Can know by table 1-3 experimental data result contrast; Compare with the catalyst that the traditional standard coating method is made; Its performance of catalyst sample that adopts the inventive method to apply has met or exceeded original catalyst sample, and exhaust emissions has reached best control effect and satisfied No. 4 discharge standards of country.
Table 1 is the initiation temperature experimental result of catalyst after 100 hours quick high-temps are aging of making according to the present invention.
| Catalyst sample | CO | HC | NOx |
| Sample of the present invention | 322℃ | 324℃ | 326℃ |
| Former press proof article | 358℃ | 350℃ | 355℃ |
Table 2 is in air-fuel ratio being the tail gas parameter conversion ratio experimental result of 100 hours quick high-temps of this catalyst after aging under 1 the situation
| Catalyst sample | CO | HC | NOx |
| Sample of the present invention | 99.5％ | 92.5％ | 96.5％ |
| Former press proof article | 98.0％ | 89.0％ | 93.4％ |
Table 3 is 80,000 kilometers car load durability experiment results.Satisfy No. 4 discharge standards of country (being equivalent to No. 4 standards in Europe)
Three-way catalyst staged and layered provided by the present invention applies new method, and requirement is done the catalyst metering system that applies machinery equipment and designed again to reach higher coating precision.Coating process can be accomplished by traditional hand and modern machine, is accomplished by machine but the segmentation coating is best, can guarantee the repeatability of production process like this.
Claims (8)
1. efficient tail-gas purifying three-way catalyst coating method; It is characterized in that: the single-piece catalyst carrier is exported from the tail gas import to tail gas carry out at least two segmentations; Adopt the catalyst pulp of different formulations to apply to different segmentations, the clarifier carrier surface of same segmentation is carried out once above catalyst material apply.
2. according to claims 1 described efficient tail-gas purifying three-way catalyst coating method, it is characterized in that: first coating (1) covers the half carrier of tail gas air-flow upstream extremity, and second coating (2) covers the half carrier of airflow downstream.
3. according to claims 1 described efficient tail-gas purifying three-way catalyst coating method; It is characterized in that: the 3rd coating (3) covers the big half carrier of tail gas air-flow upstream extremity; The 4th coating (4) covers the big half carrier in downstream, and interlude can have the overlapping area of coverage.
4. according to claims 1 described efficient tail-gas purifying three-way catalyst coating method; It is characterized in that: the coating method of the 5th coating (5) and the 6th coating (6) is similar with two sections twice coatings; The 5th coating (5) and the 6th coating (6) applied and roasting after carry out the coating of the 7th coating (7) again, the 7th coating (7) covers the big half carrier of upstream extremity or downstream.
5. efficient tail-gas purifying three-way catalyst coating method according to claim 1; It is characterized in that: after said clarifier carrier surface to same layering carries out each catalyst material coating; Said catalyst carrier is carried out roasting, and total roasting number of times is twice before the finished product.
6. efficient tail-gas purifying three-way catalyst staged and layered coating method according to claim 1 is characterized in that: described interlude overlay region length is no more than 33% of carrier lengths, leans on an end overlay region length to be no more than carrier lengths 66%.
7. efficient tail-gas purifying three-way catalyst staged and layered coating method according to claim 1, it is characterized in that: the number of plies of described coating is the 1-4 layer, the coating load capacity is every liter of 140-200 gram.
8. efficient tail-gas purifying three-way catalyst staged and layered coating method according to claim 5 is characterized in that: described sintering temperature is a 500-600 ℃ of degree.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011104174244A CN102513165A (en) | 2011-12-14 | 2011-12-14 | Efficient method for coating tail gas clean-up three-way catalyst |
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| CN2011104174244A CN102513165A (en) | 2011-12-14 | 2011-12-14 | Efficient method for coating tail gas clean-up three-way catalyst |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105597748A (en) * | 2015-11-13 | 2016-05-25 | 无锡威孚环保催化剂有限公司 | Segmented type ternary catalyst and preparation method thereof |
| CN105673157A (en) * | 2014-12-03 | 2016-06-15 | 福特环球技术公司 | Zoned catalyst system for reducing N2O emissions |
| CN105772023A (en) * | 2016-03-31 | 2016-07-20 | 湖南省吉安特技术有限公司 | Manufacturing method for efficient three-component catalyst coating |
| CN110801832A (en) * | 2019-10-22 | 2020-02-18 | 浙江达峰汽车技术有限公司 | Gasoline engine tail gas purification three-effect catalyst meeting national emission standard |
| CN112371118A (en) * | 2020-11-27 | 2021-02-19 | 中自环保科技股份有限公司 | Efficient automobile exhaust treatment catalyst and preparation method thereof |
| CN113262782A (en) * | 2021-05-27 | 2021-08-17 | 安徽艾可蓝环保股份有限公司 | Pd/Rh low-noble metal three-zone catalyst |
| CN115111032A (en) * | 2022-07-28 | 2022-09-27 | 湖北航特科技有限责任公司 | Single-stage double-core tail gas purification catalyst and preparation method thereof |
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| JPH11244664A (en) * | 1998-02-27 | 1999-09-14 | Hino Motors Ltd | Method and device for exhaust gas cleaning |
| CN1557530A (en) * | 2004-02-11 | 2004-12-29 | 辽宁大学 | Automobile end gas purifying method by rare element catalyzer |
| CN101180126A (en) * | 2005-05-26 | 2008-05-14 | 丰田自动车株式会社 | Catalyst for purifying exhaust gases |
| CN102131582A (en) * | 2008-12-03 | 2011-07-20 | 第一稀元素化学工业株式会社 | Exhaust gas purifying catalyst, exhaust gas purifying apparatus using same, and exhaust gas purifying method |
-
2011
- 2011-12-14 CN CN2011104174244A patent/CN102513165A/en active Pending
Patent Citations (4)
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| JPH11244664A (en) * | 1998-02-27 | 1999-09-14 | Hino Motors Ltd | Method and device for exhaust gas cleaning |
| CN1557530A (en) * | 2004-02-11 | 2004-12-29 | 辽宁大学 | Automobile end gas purifying method by rare element catalyzer |
| CN101180126A (en) * | 2005-05-26 | 2008-05-14 | 丰田自动车株式会社 | Catalyst for purifying exhaust gases |
| CN102131582A (en) * | 2008-12-03 | 2011-07-20 | 第一稀元素化学工业株式会社 | Exhaust gas purifying catalyst, exhaust gas purifying apparatus using same, and exhaust gas purifying method |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105673157A (en) * | 2014-12-03 | 2016-06-15 | 福特环球技术公司 | Zoned catalyst system for reducing N2O emissions |
| CN105597748A (en) * | 2015-11-13 | 2016-05-25 | 无锡威孚环保催化剂有限公司 | Segmented type ternary catalyst and preparation method thereof |
| CN105772023A (en) * | 2016-03-31 | 2016-07-20 | 湖南省吉安特技术有限公司 | Manufacturing method for efficient three-component catalyst coating |
| CN110801832A (en) * | 2019-10-22 | 2020-02-18 | 浙江达峰汽车技术有限公司 | Gasoline engine tail gas purification three-effect catalyst meeting national emission standard |
| CN112371118A (en) * | 2020-11-27 | 2021-02-19 | 中自环保科技股份有限公司 | Efficient automobile exhaust treatment catalyst and preparation method thereof |
| CN113262782A (en) * | 2021-05-27 | 2021-08-17 | 安徽艾可蓝环保股份有限公司 | Pd/Rh low-noble metal three-zone catalyst |
| CN115111032A (en) * | 2022-07-28 | 2022-09-27 | 湖北航特科技有限责任公司 | Single-stage double-core tail gas purification catalyst and preparation method thereof |
| CN115111032B (en) * | 2022-07-28 | 2024-02-20 | 湖北航特科技有限责任公司 | Single-stage double-core tail gas purifying catalyst and preparation method thereof |
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Application publication date: 20120627 |