CN113019363B - Tail gas treatment catalyst and application thereof - Google Patents
Tail gas treatment catalyst and application thereof Download PDFInfo
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- CN113019363B CN113019363B CN202110308463.4A CN202110308463A CN113019363B CN 113019363 B CN113019363 B CN 113019363B CN 202110308463 A CN202110308463 A CN 202110308463A CN 113019363 B CN113019363 B CN 113019363B
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/56—Platinum group metals
- B01J23/63—Platinum group metals with rare earths or actinides
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
- B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
- B01D53/9459—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts
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- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/002—Mixed oxides other than spinels, e.g. perovskite
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- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0201—Impregnation
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/024—Multiple impregnation or coating
- B01J37/0244—Coatings comprising several layers
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
- B01J37/082—Decomposition and pyrolysis
- B01J37/088—Decomposition of a metal salt
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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- B01D2258/00—Sources of waste gases
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
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- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Abstract
The invention relates to a tail gas treatment catalyst and application thereof.A carrier is taken as a substrate and is sequentially coated with a first catalyst body, a second catalyst body and a third catalyst body along the airflow direction; the first catalyst body includes a first coating layer; the second catalyst body is sequentially coated with a first coating and a third coating from top to bottom; the third catalyst body is sequentially coated with a second coating and a third coating from top to bottom; the tail gas treatment catalyst is of a three-section structure, and under the synergistic effect of the structure position, the material and the material addition ratio, the catalyst is good in ignition performance, dynamic window performance and thermal aging resistance, has a high-efficiency purification effect, effectively reduces pollutant emission, and is simple in preparation method and convenient to popularize.
Description
Technical Field
The invention relates to the technical field of tail gas treatment, and particularly relates to a tail gas treatment catalyst and application thereof.
Background
With the gradual implementation of national six-emission regulations and the continued tightening of emission limits by future regulations, the aftertreatment industry faces unprecedented technical challenges. The main pollutants of the automobile exhaust are carbon monoxide, hydrocarbon and oxynitride, the catalyst arranged in the exhaust system can be used for oxidizing the nitrogen monoxide and the hydrocarbon into carbon dioxide and water, and the oxynitride is reduced into nitrogen, so that the purification of the exhaust is realized. At present, the catalyst for purifying gasoline as the tail gas of the dye is mainly a three-way catalyst. The existing three-way catalyst is composed of a carrier coated with one or more layers of composite alumina with high specific surface area, a rare earth oxygen storage material coating and precious metals dispersed on the surface of the material. The oxygen storage material is a composite oxide containing cerium and zirconium, and the oxygen storage material can be used for regulating the proportion of an oxidizing component and a reducing component in the tail gas by adsorbing oxygen in the stored tail gas or releasing oxygen, so that carbon monoxide and hydrocarbon are oxidized, and nitrogen oxide is reduced.
In the emission test cycle of the light vehicle and the gasoline vehicle, the temperature and the speed are generally gradually increased, the emission of gaseous pollutants is mainly concentrated in the cold start stage, and how to reduce the emission of gaseous pollutants in the cold start stage is the difficulty of the current three-way catalyst technology. The three-way catalyst has good ignition performance, reduces ignition temperature, has good dynamic window performance, improves the dynamic response capability of the three-way catalyst for oxygen storage in a lower-temperature environment, and is beneficial to reducing the emission of gaseous pollutants in a cold start stage.
Meanwhile, the catalyst with good thermal aging resistance and high purification efficiency has very important significance for purifying pollutants in the cold start stage.
Disclosure of Invention
The invention aims to: aiming at the technical problems of poor ignition performance, poor dynamic window performance, poor thermal aging resistance and low purification efficiency of the tail gas treatment catalyst in the prior art, the tail gas treatment catalyst and the application thereof are provided; the catalyst has the advantages of good ignition performance, good dynamic window performance, good thermal aging resistance, high-efficiency purification effect, effective reduction of pollutant emission, simple preparation method and convenient popularization.
In order to achieve the purpose, the invention adopts the technical scheme that:
an exhaust gas treatment catalyst takes a carrier as a substrate, and a first catalyst body, a second catalyst body and a third catalyst body are sequentially coated along the direction of airflow;
the first catalyst body includes a first coating layer; the second catalyst body is sequentially coated with a first coating and a third coating from top to bottom; the third catalyst body is sequentially coated with a second coating and a third coating from top to bottom;
the first coating is mainly prepared from the following raw materials:
ce modified La-Al 2 O 3 30-100 g/L of material; 40-100 g/L of first oxygen storage material; precious metal Rh 3-20 g/ft 3 Noble metal Pd and/or Pt 10-200 g/ft 3 ；
The second coating is mainly prepared from the following raw materials:
La-Al 2 O 3 20-120 g/L of material; the first oxygen storage material is 20-120 g/L; the second oxygen storage material is 5-120 g/L; precious metal Rh 3-20 g/ft 3 ；
The third coating is mainly prepared from the following raw materials:
La-Al 2 O 3 20-100 g/L of material; 30-120 g/L of third oxygen storage material; one or two of noble metals Pd and Pt are 10-50 g/ft 3 。
The invention discloses a tail gas treatment catalyst which is of a three-section structure and comprises a first catalyst body, a second catalyst body and a third catalyst body, wherein the first catalyst body comprises a first coating, and the first coating is mainly Ce-modified La-Al 2 O 3 The material, the first oxygen storage material, the precious metal Rh and/or Pd, pt; the second catalyst body is sequentially provided with a first coating and a third coating from top to bottom, and the third coating is mainly La-Al 2 O 3 Materials or Ce modified La-Al 2 O 3 The material, the third oxygen storage material and the noble metal; the third catalyst body is sequentially provided with a second coating and a third coating from top to bottom, and the second coating mainly comprises La-Al 2 O 3 Materials or Ce modified La-Al 2 O 3 The material, the first oxygen storage material, the second oxygen storage material and the noble metal. The catalyst has the advantages of good ignition performance, good dynamic window performance, good thermal aging resistance, high-efficiency purification effect, effective reduction of pollutant emission, simple preparation method and convenient popularization.
Further, the first catalyst body, the second catalyst body and the third catalyst body are arranged in series.
Furthermore, in the first coating, the noble metal Pd and/or Pt is 10-200 g/ft 3 Wherein, 10 to 200g/ft 3 Is the total amount of noble metals Pd and Pt; in the third coating, the noble metal Pd and/or Pt is 10-50 g/ft 3 Wherein, 10 to 50g/ft 3 Is the total amount of noble metals Pd and Pt;
further, the first coating is mainly prepared from the following raw materials:
ce modified La-Al 2 O 3 50-100 g/L of material; 40-100 g/L of first oxygen storage material; noble metal Rh 5-20 g/ft3 and noble metal Pd and/or Pt 50-200 g/ft 3 ；
The second coating is mainly prepared from the following raw materials:
La-Al 2 O 3 30-120 g/L of material; the first oxygen storage material is 30-120 g/L; 10-120 g/L of second oxygen storage material; noble metal Rh 5-20 g/ft 3 ；
The third coating is mainly prepared from the following raw materials:
30-100 g/L of La-Al2O3 material; the third oxygen storage material is 30-120 g/L; one or two of noble metals Pd and Pt is 20-50 g/ft 3 。
Further, the oxygen release rate of the first catalyst body > the oxygen release rate of the second catalyst body > the oxygen release rate of the third catalyst body.
Further, the oxygen release amount of the first catalyst body is less than that of the second catalyst body and less than that of the third catalyst body.
Wherein, the first catalyst body is only provided with a layer of thinner coating, and the first coating adopts Ce modified La-Al 2 O 3 The material and the adding proportion of each raw material are adjusted in a targeted manner, so that the catalyst has excellent ignition performance, is favorable for temperature rise and is favorable for quick ignition of the catalyst. Meanwhile, under the synergistic effect of the positions and the amounts of the first oxygen storage material, the second oxygen storage material and the third oxygen storage material, the oxygen storage rates of the first catalyst body, the second catalyst body and the third catalyst body are enabled to be in a sequence from high to low, and the oxygen storage amounts are enabled to be from low to high, so that the dynamic response capability of the three-way catalyst for oxygen storage in a low-temperature environment can be improved according to the gradual increasing change condition of the temperature and the speed of the catalyst, the whole catalyst has good dynamic window performance, the purification effect of the catalyst reaches the optimal state, and the emission of pollutants is reduced. Thus, the first catalyst body has high content density of noble metal, high oxygen storage rate and high oxygen removal rateThe fuel performance is good, and the pollutant emission of a cold start section can be effectively reduced. The second catalyst body has higher noble metal density, takes oxygen storage and release rate and oxygen storage capacity into consideration, has higher conversion rate in a medium-low temperature state, and can effectively reduce pollutant emission in the medium-low temperature state by cooperating with the first catalyst body. The third catalyst body further improves the oxygen storage amount on the basis of taking the oxygen storage and release rate into consideration through material matching, and can effectively reduce the emission of pollutants at a high-temperature high-airspeed stage. Moreover, the Ce modified La-Al is adopted in the invention 2 O 3 Due to the interaction between the material and the noble metal and the cerium, the freshness of the catalyst can be improved, the sintering of the noble metal after thermal aging can be inhibited, and the thermal aging resistance of the catalyst is improved.
Further, in the second coating layer, the La-Al 2 O 3 The material can be La-Al modified by Ce 2 O 3 And (4) replacing materials. Further, in the third coating, the La-Al 2 O 3 The material can be La-Al modified by Ce 2 O 3 And (4) replacing materials.
Further, the second coating also comprises noble metals Pd and Pt 10-50 g/ft 3 。
Further, in the first coating layer, the first oxygen storage material is used for supporting a noble metal Rh and can also be used for supporting part of noble metals Pd and Pt; the Ce modified La-Al 2 O 3 The material is used for supporting all or part of Pd or Pt. In the second coating, the first oxygen storage material is used for loading noble metal Rh, and the second oxygen storage material is used for loading part of noble metal Pd and all noble metals Pt, la-Al2O3 or Ce modified La-Al 2 O 3 The material is used for supporting part of the noble metal Pd. In the third coating, la-Al 2 O 3 Materials or Ce modified La-Al 2 O 3 The material is used for supporting part of metal Pd, and the third oxygen storage material is used for remaining noble metal Pd and all noble metal Pt.
Further, the length of the first catalyst body accounts for 10% -85% of the total length of the catalyst; the length of the second catalyst body accounts for 10-85% of the total length of the catalyst; the length of the third catalyst body accounts for 5-80% of the total length of the catalyst. The length ratios of the first catalyst body, the second catalyst body and the third catalyst body are related to the engine displacement, the volume of the first catalyst body is more than 10% of the engine displacement, the volume sum of the first catalyst body and the second catalyst body is more than 20% of the engine displacement, and the length setting in the actual use process is related to the volume of a front-stage catalyst and the volume of an engine. The first catalyst body, the second catalyst body and the third catalyst body may be disposed continuously or discontinuously, when disposed continuously, the sum of the lengths of the first catalyst body, the second catalyst body and the third catalyst body is 100%, and when disposed discontinuously, the sum of the lengths of the first catalyst body, the second catalyst body and the third catalyst body may be less than 100%.
Further, the carrier is a ceramic matrix or a metal honeycomb matrix; the ceramic matrix is cordierite, cordierite-alumina, silicon nitride, alumina-magnesia-silica, zircon, alumina or aluminosilicate.
Further, the first oxygen storage material, the second oxygen storage material and the third oxygen storage material are each mainly composed of ceria and zirconia, wherein the weight ratio of ceria to zirconia in the first oxygen storage material is 15 to 35: third oxygen storage material > second oxygen storage material > first oxygen storage material. The weight ratio of the cerium oxide to the zirconium oxide has a close relationship with the oxygen storage rate and the oxygen discharge amount of the oxygen storage material, and the oxygen storage rates of the first catalyst body, the second catalyst body and the third catalyst body can be increased from high to low and the oxygen storage amounts can be increased from small to large by setting the proportion of the cerium oxide to the zirconium oxide in the first oxygen storage material, the second oxygen storage material and the third oxygen storage material and setting the positions of the first oxygen storage material, the second oxygen storage material and the third oxygen storage material, so that the dynamic response capability of the three-way catalyst for oxygen storage in a low-temperature environment can be improved according to the gradually increasing change condition of temperature and speed, the whole catalyst has good dynamic window performance, the purification effect of the catalyst reaches an optimal state, and the emission of pollutants is reduced.
Further, in the first coating, the Ce modified La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material is 0.5-1.5; in the second coating layer, the La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material to the second oxygen storage material is 1: 2-3; in the third coating, the La-Al 2 O 3 The weight ratio of the material to the third oxygen storage material is 0.5-1.5. Through extensive experimental research, the inventors found that the weight ratio of the alumina material to the oxygen storage material in the first coating layer, the second coating layer and the third coating layer directly affects the purification effect of the final catalyst, and the purification efficiency of the catalyst is reduced below the ratio range or above the ratio range, possibly because the adsorption performance is affected due to the reduction of the alumina ratio compared with the ratio, and the oxygen storage performance of the catalyst is affected due to the too low amount of the oxygen storage material, which is not favorable for the air-fuel ratio adjustment. Preferably, in the first coating, the Ce modified La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material is 1.0-1.5; in the second coating layer, the La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material to the second oxygen storage material is 1: 2-2.5; in the third coating, the La-Al 2 O 3 The weight ratio of the material to the third oxygen storage material is 1.0-1.5.
Further, the coating amount of the first catalyst body is 80 to 180g/L.
Further, the coating amount of the second catalyst body is 200 to 300g/L.
Further, the coating amount of the third catalyst body is 200 to 350g/L.
Further, ce modified La-Al 2 O 3 The material is mainly prepared by the following method,
step 1, stirring and dissolving a dispersing agent in water to obtain a first mixture;
step 2, taking cerium sol or soluble cerium salt, and stirring and mixing the cerium sol or the soluble cerium salt with the first mixture obtained in the step 1 to obtain a second mixture;
step 3, mixing the second mixture obtained in the step 2 with La-Al 2 O 3 Mixing the materials, and stirring for 20-60 min to obtain a third mixture;
step 4, drying the third mixture obtained in the step 3 at the temperature of between 60 and 150 ℃ for 0.5 to 5 hours;
step 5, calcining the material dried in the step 4 at 500-800 ℃ for 1-3 h, cooling and grinding to obtain Ce modified La-Al 2 O 3 A material.
Further, the dispersant is one or more of organic acid, organic base, ester, alcohol and organic high molecular polymer. Such as hydroxymethyl cellulose.
Further, in the step 3, the second mixture obtained in the step 2 and the La-Al loaded with the noble metal are mixed 2 O 3 And (4) mixing the materials.
Further, in the step 2, ceO in the cerium sol or the soluble cerium salt 2 With La-Al 2 O 3 The mass ratio is 2-20.
Further, the first coating, the second coating and the third coating are prepared by the following method:
s1, preparing a coating catalyst material;
and S2, adding a binder and an auxiliary agent into the catalyst material obtained in the step S1, performing ball milling until the average particle size is 2-6 microns and the solid content is 30-50% to obtain coating slurry, coating the coating slurry to a corresponding position, drying at 60-150 ℃ for 0.5-5 h, and roasting at 480-580 ℃ for 1-3 h to complete coating preparation, wherein the coating slurry of the first coating is used for coating a carrier and a third coating, the coating slurry of the second coating is used for coating the third coating, and the coating slurry of the third coating is used for coating the carrier.
Furthermore, the auxiliary agent is one or more of barium salt, strontium salt and salt substances formed by rare earth elements.
Further, in the first coating layer, the coating catalyst material is prepared by the following method,
according to the measurement, the noble metal Rh and part of the noble metals Pd and Pt are loaded on the first oxygen storage material by adopting an impregnation method, a precipitation method or a reduction method, and the rest Pd and Pt are loaded on the Ce modified La-Al by adopting the impregnation method, the precipitation method or the reduction method 2 O 3 Mixing the materials, drying at 60-150 ℃ for 0.5-5h, and roasting at 400-600 ℃ for 1-3 h to obtain the coating catalyst material.
Further, in the second coating layer, the coating catalyst material is prepared by the following method,
according to the measurement, a precious metal Rh is loaded on a first oxygen storage material by adopting an impregnation method, a precipitation method or a reduction method, a part of heavy metal Pd and all heavy metal Pt are loaded on a second oxygen storage material by adopting the impregnation method, the precipitation method or the reduction method, and then the rest heavy metal Pd is loaded on La-Al by adopting the impregnation method, the precipitation method or the reduction method 2 O 3 Mixing the materials, drying at 60-150 ℃ for 0.5-5h, and roasting at 400-600 ℃ for 1-3 h to obtain the coating catalyst material.
Further, in the third coating layer, the coating catalyst material is prepared by the following method,
according to the measurement, part of heavy metal Pd and all heavy metal Pt are loaded on a third oxygen storage material by adopting an impregnation method, a precipitation method or a reduction method, and the rest metal Pd is loaded on La-Al by adopting the impregnation method, the precipitation method or the reduction method 2 O 3 Mixing the materials, drying at 60-150 ℃ for 0.5-5h, and roasting at 400-600 ℃ for 1-3 h to obtain the coating catalyst material.
Further, the Ce modified La-Al 2 O 3 The process can be carried out before the noble metal loading process or after the noble metal loading process.
Further, the precursor of the noble metal can be a noble metal salt solution, and can also be a noble metal soluble salt.
Another object of the present invention is to provide use of the above-described exhaust gas treatment catalyst.
An application of tail gas catalyst in purifying the tail gas of light gasoline car.
The catalyst has simple preparation method and good purification effect, and is convenient for large-scale popularization and application.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
1. the invention discloses a tail gas treatment catalyst which is of a three-section structure and is divided into a first catalyst body, a second catalyst body and a third catalyst body, wherein the first catalyst body comprises a first coating, and the first coating is mainly Ce-modified La-Al 2 O 3 The material, the first oxygen storage material, the precious metal Rh and/or Pd, pt; the second catalyst body is sequentially provided with a first coating and a third coating from top to bottom, and the third coating is mainly La-Al 2 O 3 Materials or Ce modified La-Al 2 O 3 The material, the third oxygen storage material and the noble metal; the third catalyst body is sequentially provided with a second coating and a third coating from top to bottom, and the second coating mainly comprises La-Al 2 O 3 Materials or Ce modified La-Al 2 O 3 The material, the first oxygen storage material, the second oxygen storage material and the noble metal. The first catalyst body provided by the invention is only provided with a thin coating, and the first coating adopts Ce modified La-Al 2 O 3 The catalyst has excellent ignition performance, is beneficial to temperature rise and is beneficial to rapid ignition of the catalyst.
2. Under the synergistic effect of the positions and the amounts of the first oxygen storage material, the second oxygen storage material and the third oxygen storage material, the oxygen storage rates of the first catalyst body, the second catalyst body and the third catalyst body are enabled to be in the order of from high to low, and the oxygen storage amount is enabled to be from low to high, so that the dynamic response capability of the three-way catalyst for oxygen storage in a low-temperature environment can be improved according to the gradual increasing change condition of temperature and speed, the whole catalyst has good dynamic window performance, the purification effect of the catalyst reaches the best state, and the emission of pollutants is reduced.
3. The first catalyst body has high content density of noble metal, high oxygen storage and release rate and good ignition performance, and can effectively reduce the pollutant emission at the cold start section; the second catalyst body has higher noble metal density, takes the oxygen storage and release rate and the oxygen storage quantity into consideration, has higher conversion rate in a medium-low temperature state, and can effectively reduce the pollutant emission in the medium-low temperature state by cooperating with the first catalyst body; the third catalyst body further improves the oxygen storage amount on the basis of taking the oxygen storage and release rate into consideration through material matching, and can effectively reduce the emission of pollutants at a high-temperature high-airspeed stage.
4. The catalyst disclosed by the invention is subjected to emission test according to the WLTC circulation in the national standard GB18352.6-2016 < emission limit of light automobile pollutants and the measurement method (sixth stage of China), CO, THC and NOx can meet the national standard VIb limit, and in the emission of fresh catalyst, CO can be controlled to be within 23mg/km, THC can be controlled to be within 16mg/km, and Nox can be controlled to be within 13mg/km, so that the catalyst has very high market application value.
5. The three-way catalyst consists of the first coating, the second coating and the third coating, and the total coating times are at most three times because the third coating is not coated in the quantitative coating process of the catalyst, so that the number of processes is reduced compared with the conventional three-way catalyst with four-layer coating by segmentation and layering.
6. The invention adopts Ce to modify La-Al 2 O 3 Due to the interaction between the material and the noble metal and the cerium, the freshness of the catalyst can be improved, the sintering of the noble metal after thermal aging can be inhibited, and the thermal aging resistance of the catalyst is improved.
Drawings
Fig. 1 is a schematic view of the structure of the exhaust gas catalyst of the present invention.
Icon: 1-a substrate; 2-a first coating; 3-a second coating; 4-third coating.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
The structure of the tail gas treatment catalyst is shown in figure 1, a carrier is used as a substrate 1, and a first catalyst body, a second catalyst body and a third catalyst body are sequentially arranged on the substrate 1 along the airflow direction; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. Wherein the gas flow direction is the direction indicated by a in fig. 1, a portion indicated by a in fig. 1 is a first catalyst body length portion, a portion indicated by b is a second catalyst body length portion, and a portion indicated by c is a third catalyst body length portion. Ce modified La-Al 2 O 3 The preparation process of the material comprises the following steps:
1) Adding 2g of dispersing agent into 2000g of water, and fully stirring;
2) CeO is weighed 2 370.4g of 27% cerium sol is put into a beaker, 1500g of the dispersant (hydroxymethyl cellulose) solution pre-dissolved in the step 1 is added into the beaker, and a magnetic stirrer is used for stirring until the dispersant is uniformly dispersed;
3) Adding 900g of La-Al into the beaker in the step 2 2 O 3 Catalyzing materials, and stirring for 40min;
4) Transferring the material prepared in the step (3) to an oven for drying, wherein the temperature is set to be 90 ℃, and the drying time is 3 hours;
5) Putting the catalytic material dried in the step 4 into a muffle furnace for roasting, setting the high-temperature zone at 700 ℃, maintaining the roasting time of the high-temperature zone for 2 hours, and crushing for later use after roasting is finished to prepare a modified material;
third coating 4 preparation process (Pt: pd: rh =5, 10g/ft 3 )：
1) 8.452g of palladium nitrate (Pd content: 1.279 g) was weighed out and dissolved in 322g of deionized water and 298.7g of La-Al 2 O 3 Loading noble metal by using an isometric impregnation method, drying at 90 ℃ for 5h, and roasting at 500 ℃ for 2h to prepare catalyst powder 1; 4.406g of platinum nitrate (Pt content 0.640 g) were weighed out and dissolved in 180g of deionized water299.4g of a third oxygen storage material (CeO) weighed out 2 ：ZrO 2 50) carrying out noble metal loading by using an isometric impregnation method, drying at 90 ℃ for 5h, and roasting at 500 ℃ for 2h to prepare catalyst powder 2;
2) Adding 92g of catalyst powder 1, 184g of catalyst powder 2, 55.86g of aluminum nitrate, 310g of deionized water and 24g of barium carbonate, and performing ball milling for 30min, wherein the solid content is 45 percent, and the particle size is 3.8 mu m;
3) Coating was quantitatively performed from the exhaust end at 101.6 × 118/750 (size of support: diameter, length/mesh number) of the carrier, the coating height was 88mm, the slurry coating amount was 214g, dried at 90 c and then baked at 480 c for 2 hours, to form the third coating layer 4.
Second coating 3 preparation process (Pt: pd: rh =4, 18g/ft 3 )：
(1) 9.757g of palladium nitrate (Pd content: 1.476 g) was weighed out and dissolved in 102g of deionized water and 98.7g of La-Al 2 O 3 Loading noble metal by using an isometric impregnation method, drying at 90 ℃ for 5h, and roasting at 500 ℃ for 2h to prepare catalyst powder 3; weighing 9.532g of rhodium nitrate (Rh content of 0.886 g) and dissolving in 165g of deionized water, and weighing 298.1g of first oxygen storage material (CeO) 2 ：ZrO 2 25 is adopted as the raw material, 75) an isometric impregnation method is adopted to carry out noble metal loading, drying is carried out at 90 ℃ for 5h, and roasting is carried out at 500 ℃ for 2h to prepare catalyst powder 4; weighing 6.101g of platinum nitrate (Pt content is 0.886 g) and dissolving in 170g of deionized water, and weighing 298.2g of second oxygen storage material (CeO) 2 ：ZrO 2 35) carrying out noble metal loading by using an isometric impregnation method, drying at 90 ℃ for 5h, and roasting at 500 ℃ for 2h to prepare a catalyst powder material 5;
(2) Adding 55.2g of catalyst powder 3, 110.4g of catalyst powder 4, 110.4g of catalyst powder 5, 55.86g of aluminum nitrate, 501g of deionized water and 18g of barium carbonate into a ball milling tank for ball milling and pulping, wherein the ball milling is carried out for 30min, the solid content is 35 percent, and the granularity is 3.5 mu m;
(3) Quantitatively coating on a carrier of 101.6X 118/750 from the exhaust end, coating height of 58mm, coating amount of slurry of 174.7g, drying at 90 deg.C, and calcining at 480 deg.C for 2h to form a second coating 3.
First coating 2 preparation process (Pt: pd: rh =5, 23, 33g/ft 3 )：
1) 44.088g of palladium nitrate (Pd content: 6.671 g) and 8.120g of platinum nitrate (Pt content: 1.191 g) were mixed and dissolved in 280g of deionized water and 293.3g of Ce-modified La-Al 2 O 3 Loading noble metal by using an isometric impregnation method, drying at 90 ℃ for 5h, and roasting at 500 ℃ for 2h to prepare catalyst powder 6; 6.410g of rhodium nitrate (Rh content: 0.596 g) was weighed out and dissolved in 165g of deionized water, and 299.4g of the first oxygen storage material (CeO) 2 ：ZrO 2 25, 75) carrying out noble metal loading by using an isometric impregnation method, drying at 90 ℃ for 5h, and roasting at 500 ℃ for 2h to prepare a catalyst powder material 7;
2) Adding 92g of catalyst powder 6, 184g of catalyst powder 7, 55.86g of aluminum nitrate, 403g of deionized water and 24g of barium carbonate into a ball milling tank for ball milling and pulping, wherein ball milling is carried out for 30min, the solid content is 40%, and the particle size is 3.7 microns;
3) The coating was quantitatively applied to a carrier of 101.6X 118/750 at a coating height of 60mm to a coating amount of 176g/L from the inlet end, dried at 90 ℃ and then baked at 480 ℃ for 2 hours to form the first coating layer 2.
As shown in fig. 1, the ratio of the length of the first catalyst body to the length of the second catalyst body to the length of the third catalyst body was 25.4%, and 49.2%, respectively. The coating sequence is that the third coating 4 is applied first, then the second coating 3 is applied, and finally the first coating 2 is applied.
Wherein, the Ce in the first coating 2 is modified into La-Al 2 O 3 48g/L of material; 96g/L of first oxygen storage material; noble metal Rh 5g/ft 3 Noble metal Pd 23g/ft 3， Noble metal Rt 5g/ft 3 。
In the second coating 3, la-Al 2 O 3 26g/L of material; 52g/L of first oxygen storage material; 52g/L of second oxygen storage material; noble metal Rh 4g/ft 3 (ii) a pt and pd contents 14g/ft 3 ，Pt:Pd＝4:10。
In the third coating 4, la-Al 2 O 3 45g/L of material; 90g/L of third oxygen storage material; noble metal Pd and noble metal Pt 10g/ft 3 ，Pt:Pd＝5:5。
Example 2
The carrier is taken as a substrate 1 and is sequentially provided with a first catalyst body and a second catalyst body along the direction of air flowAn agent body and a third catalyst body; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. The length ratios of the first catalyst body, the second catalyst body, and the third catalyst body were 30.1%, 20.5%, and 49.4%, respectively. The coating sequence is that the third coating 4 is applied first, then the second coating 3 is applied, and finally the first coating 2 is applied. The respective coating amounts of the first coating layer 2, the second coating layer 3 and the third coating layer 4 were the same as in example 1. Ce-modified La-Al in example 2 2 O 3 The preparation process of the material was the same as that in example 1, and in example 2, the weight ratio of ceria and zirconia in the first oxygen storage material was 15.
Wherein, the Ce in the first coating 2 is modified into La-Al 2 O 3 98g/L of material; 100g/L of first oxygen storage material; noble metal Rh 8g/ft 3 Noble metal Pd 50g/ft 3 ；
In the second coating 3, ce modified La-Al 2 O 3 20g/L of material; 40g/L of first oxygen storage material; 40g/L of second oxygen storage material; noble metal Rh 15g/ft 3 (ii) a Pt and Pd content 14g/ft 3 ，Pt:Pd＝4:10。
In the third coating 4, la-Al 2 O 3 The material is 30g/L; the third oxygen storage material is 30g/L; noble metal Pd and noble metal Pt 15g/ft 3 ，Pt:Pd＝5:10。
Example 3
A first catalyst body, a second catalyst body and a third catalyst body are sequentially arranged along the airflow direction by taking the carrier as a substrate 1; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. The length ratios of the first catalyst body, the second catalyst body, and the third catalyst body were 12.5%, 33.1%, and 54.4%, respectively. Coating processThe sequence is that the third coating 4 is applied first, then the second coating 3 is applied, and finally the first coating 2 is applied. The respective coating amounts of the first coating layer 2, the second coating layer 3 and the third coating layer 4 were the same as in example 1. Ce-modified La-Al in example 2 2 O 3 The preparation process of the material was the same as that in example 1, and in example 2, the weight ratio of ceria and zirconia in the first oxygen storage material was 15.
Wherein, the Ce in the first coating 2 is modified into La-Al 2 O 3 The material is 30g/L; 52g/L of first oxygen storage material; precious metal Rh 10g/ft 3 Noble metal Pd 18g/ft 3 ；
In the second coating 3, ce modified La-Al 2 O 3 60g/L of material; 120g/L of first oxygen storage material; 120g/L of second oxygen storage material; precious metal Rh 10g/ft 3 (ii) a pt is 5g/ft 3 Pd is 5g/ft, pt: pd = 5;
in the third coating 4, ce modified La-Al 2 O 3 The material is 90g/L; the third oxygen storage material is 100g/L; noble metal Pd 36g/ft 3 。
Example 4
A first catalyst body, a second catalyst body and a third catalyst body are sequentially arranged along the airflow direction by taking the carrier as a substrate 1; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. The length ratios of the first catalyst body, the second catalyst body, and the third catalyst body were 10%, 15%, and 75%, respectively. The coating sequence is that the third coating 4 is applied first, then the second coating 3 is applied, and finally the first coating 2 is applied. The respective coating amounts of the first coating layer 2, the second coating layer 3 and the third coating layer 4 were the same as in example 1. Ce-modified La-Al in example 2 2 O 3 The preparation process of the material was the same as that of example 1, while, in example 2, the weight ratio of ceria and zirconia in the first oxygen storage material was 20The weight ratio of the cerium oxide to the zirconium oxide in the second oxygen storage material is 40.
Wherein, the Ce in the first coating 2 is modified into La-Al 2 O 3 The material is 100g/L; 70g/L of first oxygen storage material; noble metal Rh 8g/ft 3 Noble metal Pd 120g/ft 3 ；
In the second coating 3, la-Al 2 O 3 The material is 30g/L; the first oxygen storage material is 90g/L; 75g/L of second oxygen storage material; noble metal Rh 4g/ft 3 (ii) a pt plus pd 14g/ft 3 ；，Pt:Pd＝4:10；
In the third coating 4, ce modified La-Al 2 O 3 120g/L of material; 80g/L of third oxygen storage material; noble metal Pd and noble metal Pt 40g/ft 3 ，Pt:Pd＝10:30。
Example 5
A first catalyst body, a second catalyst body and a third catalyst body are sequentially arranged along the airflow direction by taking the carrier as a substrate 1; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. The length ratios of the first catalyst body, the second catalyst body, and the third catalyst body were 40.2%, 26.8%, and 33%, respectively. The coating sequence is that the third coating 4 is applied first, then the second coating 3 is applied, and finally the first coating 2 is applied. The respective coating amounts of the first coating layer 2, the second coating layer 3 and the third coating layer 4 were the same as in example 1. Ce-modified La-Al in example 2 2 O 3 The preparation process of the material was the same as that in example 1, and in example 2, the weight ratio of ceria and zirconia in the first oxygen storage material was 30.
Wherein, the Ce in the first coating 2 is modified into La-Al 2 O 3 66g/L of material; 80g/L of first oxygen storage material; precious metal Rh 10g/ft 3 Noble metal Pd 100g/ft 3 ；
In the second coating 3, la-Al 2 O 3 45g/L of material; the first oxygen storage material is 90g/L; the second oxygen storage material is 100g/L; precious metal Rh 20g/ft 3 Noble metals Pd and noble metals Pt 14g/ft 3 ，Pt:Pd＝4:10；
In the third coating 4, la-Al 2 O 3 72g/L of material; 90g/L of third oxygen storage material; noble metal Pd and noble metal Pt 30g/ft 3 ，Pt:Pd＝10:20。
Example 6
A first catalyst body, a second catalyst body and a third catalyst body are sequentially arranged along the airflow direction by taking a carrier as a substrate 1; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. The length ratios of the first catalyst body, the second catalyst body, and the third catalyst body were 20.5%, 32.9%, and 46.6%, respectively. The coating sequence is that the third coating 4 is applied first, then the second coating 3 is applied, and finally the first coating 2 is applied. The respective coating amounts of the first coating layer 2, the second coating layer 3 and the third coating layer 4 were the same as in example 1. Ce-modified La-Al in example 2 2 O 3 The preparation process of the material was the same as that in example 1, and in example 2, the weight ratio of ceria and zirconia in the first oxygen storage material was 25.
Wherein, the Ce in the first coating 2 is modified into La-Al 2 O 3 80g/L of material; the first oxygen storage material is 90g/L; noble metal Rh 6g/ft 3 Noble metal Pd 60g/ft 3 ；
In the second coating 3, la-Al 2 O 3 50g/L of material; 100g/L of first oxygen storage material; the second oxygen storage material is 100g/L; noble metal Rh 6g/ft 3 (ii) a pt plus pd 14g/ft 3 ，Pt:Pd＝4:10；
In the third coating 4, la-Al 2 O 3 20g/L of material; the third oxygen storage material is 30g/L; noble metal Pd and noble metal Pt 50g/ft 3 ，Pt:Pd＝10:40。
Comparative example 1
The exhaust gas treatment catalyst prepared in comparative example 1 has the same structure as that of the exhaust gas treatment catalyst of example 1 except that Ce-modified La — Al in example 1 2 O 3 Materials used in comparative example 1 were La-Al 2 O 3 A material. The composition of the remaining raw materials and the raw material addition concentration in the first catalyst body, the second catalyst body, and the third catalyst body in comparative example 1 were the same as those in example 1.
Comparative example 2
The structure of the exhaust gas treatment catalyst prepared in comparative example 2 was the same as that of the exhaust gas treatment catalyst of example 1, except that the comparative example 2 changed the relationship of the weight ratio of ceria and zirconia in the first, second and third oxygen storage materials, and the total amount of addition of ceria and zirconia in the first, second and third oxygen storage materials was the same as that in example 1, wherein, in comparative example 2, the weight ratio of the first oxygen storage material ceria and zirconia was 25.
Comparative example 3
The structure of the exhaust gas treatment catalyst prepared in comparative example 3 was the same as that of the exhaust gas treatment catalyst of example 1, except that in comparative example 3, the relationship of the weight ratio of ceria and zirconia in the first, second and third oxygen storage materials was changed, and the total amount of addition of ceria and zirconia in the first, second and third oxygen storage materials was the same as that in example 1, wherein in comparative example 3, the weight ratio of the first oxygen storage material ceria and zirconia was 10, the weight ratio of the second oxygen storage material ceria and zirconia was 20.
Comparative example 4
Comparative example 4 the exhaust gas treatment catalyst structure prepared in comparative example 4 was identical to that of example 1 except that comparative example 4 changed the weight ratio of the modifying material to the oxygen storage material in the first coat 2, the second coat 3 and the third coat 4, and the total weight of the modifying material and the oxygen storage material in each coat was identical to that of example 1. Wherein, in comparative example 4, in the first coating 2, the Ce modified La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material is 0.2 2 O 3 The weight ratio of the material to the first oxygen storage material to the second oxygen storage material is 1:1; in the third coating 4, the La-Al 2 O 3 The weight ratio of material to the third oxygen storage material is 2. The composition of the remaining raw materials and the raw material addition concentration in the first catalyst body, the second catalyst body, and the third catalyst body in comparative example 4 were the same as those in example 1.
Comparative example 5
Comparative example 5 the structure of the exhaust gas treatment catalyst was changed as compared with example 1, comparative example 5 contained only the second catalyst body and the third catalyst body without the first catalyst body provided to the catalyst of example 1, the raw material and the added amount of the first coat layer 2 in the second catalyst body in comparative example 5 were the same as the added total amount of the first coat layer 2 in example 1, and the raw material components and the added total amount of the second coat layer 3 and the third coat layer 4 in the second catalyst body and the third catalyst body in comparative example 5 were the same as example 1.
Comparative example 6
Comparative example 6 the structure of the exhaust gas treatment catalyst was changed as compared with example 1, comparative example 6 contained only the first catalyst body and the second catalyst body without providing the third catalyst body as compared with the catalyst of example 1, the raw material and the addition amount of the third coat layer 4 in the second catalyst body in comparative example 6 were the same as the total amount of the addition of the third coat layer 4 in example 1, and the raw material components and the total amount of the addition of the first coat layer 2 in the first catalyst body and the second catalyst body in comparative example 6 were the same as in example 1.
Emission test:
the catalyst prepared in example 1 is prepared into a catalyst sample with the length, width and height of 1 inch, the catalyst sample is subjected to a temperature rise activity test at 100-450 ℃ in a gasoline car sample activity test device, and the simulated atmosphere contains CO and C 3 H 4 、C 3 H 6 、H 2 、H 2 O、CO 2 NO and O 2 The test air-fuel ratio is the theoretical air-fuel ratio, and the airspeed is 40000/h. The test results are shown in table 1.
TABLE 1 light-off temperature fresh data T50 (. Degree. C.)
| CO | THC | NOX | |
| Example 1 | 147 | 220 | 222 |
The catalyst body prepared by the invention has lower ignition temperature and is beneficial to reducing the pollutant emission in the cold start stage.
The emission tests of examples 1 to 6 and comparative examples 1 to 6 were carried out on 1.8L domestic six-commercial gasoline vehicles produced by a company according to the WLTC cycle of standard GB18352.6-2016 emission limit for light-duty car pollutants and methods of measurement (sixth stage of china). The emission test respectively tests the gaseous pollutant emission of the catalyst in a fresh state and an aging state, the catalyst aging test condition refers to 'quick aging test cycle A' in a standard HJ T331-2006, and relevant parameters are shown in a table 2.
TABLE 2 Rapid aging test cycle A
The emissions data for WLTC cycle testing on whole-vehicle hubs for fresh catalysts prepared in examples 1-6 and comparative examples 1-6 are shown in table 3.
TABLE 3 test data
The emissions data for WLTC cycle testing on the entire vehicle hub after aging of the catalysts prepared in examples 1-6 and comparative examples 1-6 are shown in table 4.
TABLE 4 test data
As can be seen from the test results in tables 3 and 4, the tail gas purification test data using the three-stage tail gas catalyst provided by the invention shows that the catalyst has good catalytic performance in a fresh state, and the catalyst provided by the invention can still maintain good catalytic performance after being aged by a rackAnd (4) performance is improved. Comparative example 1 modified alumina material without using Ce-modified La-Al of the present invention 2 O 3 The catalytic performance of the material is obviously reduced. In comparative examples 2 to 4, the weight ratio of cerium oxide to zirconium oxide in the oxygen storage material was changed, which is outside the protection range of the present invention, and the prepared catalyst reduced the dynamic window performance and the effect of purifying exhaust gas was significantly reduced. Compared with 5-6, the three-section catalyst structure provided by the invention is changed, the performances of quick light-off and good dynamic window of the catalyst are damaged, and the effect of the catalyst on purifying tail gas is obviously reduced.
The tail gas catalyst of the invention takes a carrier as a substrate 1 and is sequentially provided with a first catalyst body, a second catalyst body and a third catalyst body along the direction of air flow; the first catalyst body includes a first coating layer 2; the second catalyst body is sequentially provided with a first coating 2 and a third coating 4 from top to bottom; the third catalyst body is provided with a second coating 3 and a third coating 4 from top to bottom in sequence. The tail gas treatment catalyst is of a three-section structure, and under the synergistic effect of the structure position, the material and the material addition ratio, the catalyst is good in ignition performance, dynamic window performance and thermal aging resistance, has a high-efficiency purification effect, effectively reduces pollutant emission, and is simple in preparation method and convenient to popularize.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (8)
1. An exhaust gas treatment catalyst is characterized in that a carrier is used as a substrate (1), and a first catalyst body, a second catalyst body and a third catalyst body are sequentially coated on the substrate along the airflow direction; the first catalyst body comprises a first coating layer (2); the second catalyst body is sequentially coated with a first coating (2) and a third coating (4) from top to bottom; the third catalyst body is sequentially coated with a second coating (3) and a third coating (4) from top to bottom;
the first coatingThe layer (2) is mainly prepared from the following raw materials: ce modified La-Al 2 O 3 30-100 g/L of material; 40-100 g/L of first oxygen storage material; noble metal Rh 3-20 g/ft 3 Noble metal Pd and/or Pt 10-200 g/ft 3 ；
The second coating (3) is mainly prepared from the following raw materials: la-Al 2 O 3 20-120 g/L of material; 20 to 120g/L of the first oxygen storage material; 5 to 120g/L of a second oxygen storage material; precious metal Rh 3 to 20g/ft 3 ；
The third coating (4) is mainly prepared from the following raw materials: la-Al 2 O 3 20-100 g/L of material; 30-120 g/L of a third oxygen storage material; noble metal Pd or/and noble metal Pt 10-50 g/ft 3 (ii) a The weight ratio of the cerium oxide to the zirconium oxide in the first oxygen storage material is 15-35 to 65-85, the weight ratio of the cerium oxide to the zirconium oxide in the second oxygen storage material is 35-60 to 40-65, the weight ratio of the cerium oxide to the zirconium oxide in the third oxygen storage material is 40-80: third oxygen storage material > second oxygen storage material > first oxygen storage material.
2. The exhaust gas treatment catalyst according to claim 1, wherein in the first coating (2), the Ce-modified La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material is 0.5-1.5; in the second coating layer (3), the La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material to the second oxygen storage material is 1: 2-3; in the third coating layer (4), the La-Al 2 O 3 The weight ratio of the material to the third oxygen storage material is 0.5-1.5.
3. The exhaust gas treatment catalyst according to claim 1, wherein in the first coating (2), the Ce-modified La-Al 2 O 3 The weight ratio of the material to the first oxygen storage material is 1.0-1.5; in the second coating layer (3), the La-Al 2 O 3 Material and the first reservoirThe weight ratio of the oxygen material to the second oxygen storage material is 1: 2-2.5; in the third coating layer (4), the La-Al 2 O 3 The weight ratio of the material to the third oxygen storage material is 1.0-1.5.
4. The exhaust gas treatment catalyst according to claim 1, wherein the coating amount of the first catalyst body is 80 to 180 g/L; the coating amount of the second catalyst body is 200-300 g/L; the coating amount of the third catalyst body is 200 to 350g/L.
5. The exhaust gas treatment catalyst according to claim 1, wherein the length of the first catalyst body accounts for 10% to 85% of the total length of the catalyst; the length of the second catalyst body accounts for 10-85% of the total length of the catalyst; the length of the third catalyst body accounts for 5-80% of the total length of the catalyst.
6. The exhaust gas treatment catalyst according to any one of claims 1-5, wherein the carrier is a ceramic substrate (1) or a metal honeycomb substrate (1).
7. The exhaust gas treatment catalyst according to claim 1, wherein the Ce-modified La-Al 2 O 3 The material is mainly prepared by the following method,
step 1, stirring and dissolving a dispersing agent in water to obtain a first mixture;
step 2, taking cerium sol or soluble cerium salt, and stirring and mixing the cerium sol or the soluble cerium salt with the first mixture obtained in the step 1 to obtain a second mixture;
step 3, mixing the second mixture obtained in the step 2 with La-Al 2 O 3 Mixing the materials, and stirring for 20-60 min to obtain a third mixture;
step 4, drying the third mixture obtained in the step 3 at the temperature of between 60 and 150 ℃ for 0.5 to 5 hours;
step 5, calcining the material dried in the step 4 at 500-800 ℃ for 1-3 h to obtain the materialTo Ce modified La-Al 2 O 3 A material.
8. Use of the exhaust gas treatment catalyst according to any one of claims 1 to 7 for purifying light gasoline vehicle exhaust gases.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4591580A (en) * | 1983-01-26 | 1986-05-27 | W. R. Grace & Co. | Stabilized and doubly promoted platinum group metal catalysts for emission control and method of making same |
| CN1272400A (en) * | 1999-04-30 | 2000-11-08 | 山西净土实业有限公司 | Automobile tail gas cleaning catalyst and its preparation method |
| CN1671471A (en) * | 2002-06-27 | 2005-09-21 | 恩格哈德公司 | Multi-zone catalytic converter |
| CN101433849A (en) * | 2007-11-15 | 2009-05-20 | 贾军 | Catalyst for purifying tail gas of motor vehicle |
| 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 |
| CN106807369A (en) * | 2017-02-13 | 2017-06-09 | 安徽新态环保科技有限公司 | A kind of automobile three-way catalysts catalyst |
| CN108927168A (en) * | 2018-07-16 | 2018-12-04 | 山东艾泰克环保科技股份有限公司 | A kind of natural gas vehicle three-way catalyst and preparation method thereof |
| CN109070068A (en) * | 2016-03-09 | 2018-12-21 | 巴斯夫公司 | core/shell type hydrocarbon trap catalyst and its manufacturing method |
| CN109225316A (en) * | 2018-10-08 | 2019-01-18 | 中自环保科技股份有限公司 | A kind of exhaust gas treatment catalyst and its preparation method and application |
| WO2019043557A1 (en) * | 2017-08-28 | 2019-03-07 | Basf Corporation | Phosphorus resistant three-way catalyst |
| CN111617773A (en) * | 2020-06-04 | 2020-09-04 | 中自环保科技股份有限公司 | DOC catalytic coating with high fuel oil ignition performance and preparation method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060217263A1 (en) * | 2005-03-24 | 2006-09-28 | Tokyo Roki Co., Ltd | Exhaust gas purification catalyst |
| DE102013210270A1 (en) * | 2013-06-03 | 2014-12-04 | Umicore Ag & Co. Kg | three-way |
| CN103877975B (en) * | 2014-03-28 | 2016-02-17 | 重庆同庆环保技术有限公司 | A kind of purifying internal combustion engine tail gas three-way catalyst and preparation method thereof |
| US9956526B2 (en) * | 2015-03-24 | 2018-05-01 | Tecogen Inc. | Poison-resistant catalyst and systems containing same |
| KR20180128978A (en) * | 2016-04-22 | 2018-12-04 | 바스프 코포레이션 | A platinum group metal catalyst supported on a large pore alumina support |
| WO2019088302A1 (en) * | 2017-11-06 | 2019-05-09 | 新日本電工株式会社 | Oxygen absorbing and releasing material, catalyst, exhaust gas purifying system, and exhaust gas treatment method |
-
2021
- 2021-03-23 CN CN202110308463.4A patent/CN113019363B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4591580A (en) * | 1983-01-26 | 1986-05-27 | W. R. Grace & Co. | Stabilized and doubly promoted platinum group metal catalysts for emission control and method of making same |
| CN1272400A (en) * | 1999-04-30 | 2000-11-08 | 山西净土实业有限公司 | Automobile tail gas cleaning catalyst and its preparation method |
| CN1671471A (en) * | 2002-06-27 | 2005-09-21 | 恩格哈德公司 | Multi-zone catalytic converter |
| CN101433849A (en) * | 2007-11-15 | 2009-05-20 | 贾军 | Catalyst for purifying tail gas of motor vehicle |
| CN109070068A (en) * | 2016-03-09 | 2018-12-21 | 巴斯夫公司 | core/shell type hydrocarbon trap catalyst and its manufacturing method |
| 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 |
| CN106807369A (en) * | 2017-02-13 | 2017-06-09 | 安徽新态环保科技有限公司 | A kind of automobile three-way catalysts catalyst |
| WO2019043557A1 (en) * | 2017-08-28 | 2019-03-07 | Basf Corporation | Phosphorus resistant three-way catalyst |
| CN108927168A (en) * | 2018-07-16 | 2018-12-04 | 山东艾泰克环保科技股份有限公司 | A kind of natural gas vehicle three-way catalyst and preparation method thereof |
| CN109225316A (en) * | 2018-10-08 | 2019-01-18 | 中自环保科技股份有限公司 | A kind of exhaust gas treatment catalyst and its preparation method and application |
| CN111617773A (en) * | 2020-06-04 | 2020-09-04 | 中自环保科技股份有限公司 | DOC catalytic coating with high fuel oil ignition performance and preparation method thereof |
Non-Patent Citations (4)
| Title |
|---|
| A Review on the Pd-Based Three-Way Catalyst;Wang, JH et al.;《Catalysis Reviews-Science And Engineering》;20150102;79-144 * |
| Pt/MoO3/ZrO2催化剂的制备及三效催化性能的研究;温怡芸等;《无机材料学报》;20081115;1267-1271 * |
| 低负载量Pd和Rh三效催化剂的制备与性能低负载量Pd和Rh三效催化剂的制备与性能;张志亮;《中国优秀硕士学位论文全文数据库》;20170315;B027-1395 * |
| 用于高性能单Pd三效催化剂的复合组分CexZr1–xO2材料的制备;李红梅等;《无机材料学报》;20180823;798-804 * |
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