CN113750996B - Catalyst for enhancing purification of tail gas of internal combustion engine and preparation method thereof - Google Patents
Catalyst for enhancing purification of tail gas of internal combustion engine and preparation method thereof Download PDFInfo
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Abstract
The invention provides a catalyst for enhancing the purification of tail gas of an internal combustion engine, which comprises a carrier, a lower coating layer formed on the carrier and an upper coating layer formed on the lower coating layer, wherein the lower coating layer comprises a noble metal active component and La 2 O 3 ‑Al 2 O 3 The active components of noble metal comprise noble metal Pd and noble metal Ru, and the noble metal Pd is loaded on La 2 O 3 ‑Al 2 O 3 On the above, noble metal Ru and barium salt are dispersed by a dispersant and then are loaded on La 2 O 3 ‑Al 2 O 3 And cerium zirconium solid solution; the upper coating comprises noble metal Rh, la 2 O 3 ‑Al 2 O 3 And cerium-zirconium solid solution, noble metal Rh is supported on La 2 O 3 ‑Al 2 O 3 And cerium zirconium solid solutions. The catalyst disclosed by the invention comprises an upper coating and a lower coating, ru is added into the lower coating to enhance the purification capability of the tail gas of an internal combustion engine, ba enhances the deterioration resistance of Ru, and meanwhile, the dosage of Rh on the upper layer is reduced, so that the cost of the whole catalyst is reduced.
Description
Technical Field
The invention belongs to the technical field of catalysts, and particularly relates to a catalyst for enhancing purification of tail gas of an internal combustion engine and a preparation method thereof.
Background
The internal combustion engine catalyst is mainly a vehicle catalyst for converting carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxides (NOx) in the original row into harmless carbon dioxide (CO 2), water (H2O) and nitrogen (N2) through catalytic reaction; with the development of society, the use amount of internal combustion engines is increasing, especially the conservation amount of global motor vehicles is increasing, and the pollutants in the tail gas become one of the main sources of urban air pollution, so that not only is the health of human beings endangered, but also the ecological environment is greatly damaged, therefore, the countries are developing more and more severe tail gas emission regulations to limit the emission of gaseous pollutants, and along with the stricter regulations, people also put higher demands on the performance of catalysts.
At present, a double-coating structure is generally used for treating automobile exhaust, and precious metals such as Pt, pd, rh and the like are contained in the coating, wherein the price of Rh is increased in one path in recent years, and a cheaper alternative metal or technology is found to become a hot topic in the industry; ru with lower price has unique advantage in the conversion of NOx, so the Ru-containing catalyst has wide application prospect in the field of purifying the tail gas of the internal combustion engine.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a catalyst for enhancing the purification of the tail gas of an internal combustion engine and a preparation method thereof.
The technical scheme adopted by the invention is as follows:
a catalyst for enhancing the purification of exhaust gas from an internal combustion engine, wherein: the catalyst for enhancing the purification of the tail gas of the internal combustion engine comprises a carrier, a lower coating layer formed on the carrier and an upper coating layer formed on the lower coating layer, wherein the lower coating layer comprises a noble metal active component and La 2 O 3 -Al 2 O 3 Cerium zirconium solid solution and barium salt, the noble metal active component comprises noble metal Pd and noble metal Ru, and the noble metal Pd is loaded on La 2 O 3 -Al 2 O 3 On the above, the noble metal Ru and barium salt are dispersed by a dispersant and then loaded on La 2 O 3 -Al 2 O 3 And cerium zirconium solid solution; the upper coating comprises noble metal Rh, la 2 O 3 -Al 2 O 3 And cerium-zirconium solid solution, the noble metal Rh is supported on La 2 O 3 -Al 2 O 3 And cerium zirconium solid solutions.
Preferably, the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein: the loading capacity of the noble metal Pd in the lower coating is 5-250 g/ft 3 The loading capacity of the noble metal Ru in the lower coating is 5-100 g/ft 3 。
Preferably, the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein: the barium salt is selected from one or more of barium nitrate, barium acetate and barium sulfate, and the loading amount of the barium salt in the lower coating is 1-50 g/ft 3 。
Preferably, the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein: the dispersing agent is one or more selected from polyvinyl alcohol, polyvinylpyrrolidone and carboxymethyl cellulose.
Preferably, the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein: the loading capacity of the noble metal Rh in the upper coating is 0.1-30 g/ft 3 。
Preferably, the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein: the La is 2 O 3 -Al 2 O 3 The components in the composition are as follows by mass percent: 1 to 10 percent by weight of La 2 O 3 And 90 to 99wt% of Al 2 O 3 。
Preferably, the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein: the cerium-zirconium solid solution comprises the following components in percentage by mass: 20 to 95 weight percent ZrO 2 、5wt％～80wt％CeO 2 And 0 to 10wt% of a composite oxide selected from La 2 O 3 、Y 2 O 3 、Pr 6 O 11 、Nd 2 O 3 One or more of them.
A method for preparing a catalyst for enhancing purification of exhaust gas from an internal combustion engine, comprising the steps of:
(1) And (2) coating the following coating: adding a certain amount of deionized water into Pd solution and then dripping La into the Pd solution 2 O 3 -Al 2 O 3 Standing for 0.5-5 h, then placing into a baking oven at 80-200 ℃ to dry for 4-12 h, programming the temperature of the dried powder to 350-600 ℃ at the temperature rising rate of 0.5-25 ℃/min, roasting for 1-8 h, crushing after roasting, adding the crushed powder and cerium-zirconium solid solution into water to prepare slurry, ball-milling the slurry, and controlling the granularity to be 7-20 mu m; mixing Ru solution and barium salt, adding deionized water for dilution, adding a dispersing agent for stirring for 0.5-8 hours, dripping into the ball-milled slurry, stirring uniformly, adding 1-5 g/L aluminum gel to prepare lower coating slurry, coating the lower coating slurry on a carrier in a coating amount of 50-200 g/L, drying at 100-250 ℃ for 5-10 min, and roasting to obtain a catalyst semi-finished product;
(2) Coating of an upper layer coating: la is subjected to 2 O 3 -Al 2 O 3 Adding the cerium-zirconium solid solution and the cerium-zirconium solid solution into deionized water, uniformly mixing, ball milling, controlling the granularity to be 7-20 mu m, then dripping Rh solution into the slurry, and uniformly stirringAdding 1-5 g/L aluminum gel to prepare coating sizing agent, coating the sizing agent on the semi-finished catalyst product prepared in the step (1) according to the coating amount of 50-200 g/L, drying the semi-finished catalyst at 100-250 ℃ for 5-10 min, then heating the catalyst to 450-800 ℃ at the heating rate of 0.5-25 ℃/min, and roasting for 1-8 h to obtain the finished catalyst product.
Preferably, the preparation method of the catalyst for enhancing purification of exhaust gas of an internal combustion engine, wherein the roasting in the step (1) and the roasting in the step (2) are as follows: the catalyst is programmed to be heated to 450-800 ℃ at the heating rate of 0.5-25 ℃/min and baked for 1-8 h.
The invention has the advantages that:
the catalyst of the invention comprises an upper coating layer and a lower coating layer, wherein the noble metal Pd in the lower coating layer is supported on La 2 O 3 -Al 2 O 3 Noble metal Ru is supported on La by a dispersant 2 O 3 -Al 2 O 3 And cerium-zirconium solid solution, noble metal Rh in the upper coating layer is loaded on La 2 O 3 -Al 2 O 3 The invention enhances the purification capability of the tail gas of the internal combustion engine by adding Ru into the lower coating, enhances the deterioration resistance of Ru by Ba, reduces the dosage of Rh on the upper layer and reduces the cost of the whole catalyst
Detailed Description
The invention will be further illustrated with reference to specific examples.
Example 1
A method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine, comprising the steps of:
(1) Coating of the lower layer coating: 30g of palladium nitrate solution (10 mass% Pd) was added to 50g of deionized water and then 500g of La was added dropwise 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:49), standing for 2 hours, drying in an oven at 100deg.C for 10 hours, programming the dried powder to 450deg.C at a heating rate of 15deg.C/min, calcining for 2 hours, pulverizing, and mixing with 500g cerium zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 =40:50:10) was added to water to prepare a slurry, and the particle size was controlled to 15 μm by ball milling. 30g of nitreAdding 100g deionized water into 10mass%Ru acid ruthenium solution and 10g barium sulfate to dilute, adding 2g polyvinylpyrrolidone, stirring for 2h, then dripping into the slurry, stirring uniformly, adding 3g/L aluminum gel to prepare lower-layer coating slurry, coating the lower-layer coating slurry on a carrier with a coating amount of 100g/L, drying for 5min at 150 ℃, then heating the catalyst to 450 ℃ at a heating rate of 15 ℃/min, and roasting for 1h to obtain a semi-finished product of the catalyst;
(2) Coating of an upper layer coating: 400g of La 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:49) and 1000g of cerium zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 =25:70:5) adding 2000g of ionized water, uniformly mixing, ball milling, controlling the granularity to be 10 mu m, then dripping 10g of rhodium nitrate solution (containing 10 mass%Rh), uniformly stirring, adding 1g/L aluminum gel to prepare upper-layer coating slurry, coating the slurry on the semi-finished catalyst carrier prepared in the step (1) with the coating amount of 70g/L, drying at 200 ℃ for 5min, then programming the temperature of the catalyst to 600 ℃ at the temperature rising rate of 25 ℃/min, and roasting for 2h to obtain the finished catalyst.
Example 2
A method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine, comprising the steps of:
(1) Coating of the lower layer coating: 10g of palladium nitrate solution (10 mass% Pd) was added to 20g of deionized water and then 700g of La was added dropwise 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:24), standing for 2 hours, drying in a 100 ℃ oven for 12 hours, programming the dried powder to 550 ℃ at a heating rate of 15 ℃/min, roasting for 2 hours, crushing, and mixing with 600g of cerium-zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 =40:55:5) was added to water to prepare a slurry, and the particle size was controlled to 15 μm by ball milling. 15g of ruthenium nitrate solution (containing 10 mass%Ru) and 15g of barium nitrate are added with 100g of deionized water for dilution, then 1g of carboxymethyl cellulose is added for stirring for 4 hours, then the mixture is added into the slurry in a dropwise manner, the mixture is stirred uniformly, then 2g/L of aluminum gel is added to prepare lower coating slurry, and the lower coating slurry is coated on a carrier in a coating amount of 120g/L, and the catalyst is dried at 150 ℃ quickly after the catalyst is used for preparing the catalystHeating to 500 ℃ at a heating rate of 15 ℃/min, and roasting for 1h to obtain a semi-finished product of the catalyst;
(2) Coating of an upper layer coating: 600g La 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:49) and 2000g of cerium zirconium solid solution (ZrO 2 :CeO 2 :Nd 2 O 3 =20:75:5) adding 3000g of ionized water, uniformly mixing, ball milling, controlling the granularity to be 11 mu m, then dripping 10g of rhodium nitrate solution (containing 10 mass%Rh), uniformly stirring, adding 1g/L aluminum gel to prepare upper-layer coating slurry, coating the slurry on the semi-finished catalyst carrier prepared in the step (1) with the coating amount of 70g/L, quickly drying at 200 ℃, then programming the temperature of the catalyst to 600 ℃ at the temperature rising rate of 25 ℃/min, and roasting for 2 hours to obtain the finished catalyst.
Example 3
A method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine, comprising the steps of:
(1) Coating of the lower layer coating: 50g of palladium nitrate solution (10 mass% Pd) was added to 50g of deionized water and then 600g of La was added dropwise 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:24), standing for 2 hours, drying in an oven at 150deg.C for 8 hours, programming the dried powder to 550deg.C at a heating rate of 25deg.C/min, calcining for 2 hours, pulverizing, and mixing with 700g cerium zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 =25:70:5) was added to water to prepare a slurry, and the particle size was controlled to 15 μm by ball milling. Adding 20g of ruthenium nitrate solution (containing 10 mass%Ru) and 20g of barium acetate into 100g of deionized water for dilution, adding 2.5g of polyvinyl alcohol for stirring for 4 hours, then dropwise adding into the slurry, stirring uniformly, adding 2g/L of aluminum gel to prepare lower-layer coating slurry, coating the lower-layer coating slurry onto a carrier at a coating amount of 120g/L, rapidly drying at 150 ℃, then heating the catalyst to 500 ℃ at a heating rate of 15 ℃/min, and roasting for 1 hour to obtain a semi-finished product of the catalyst;
(2) Coating of an upper layer coating: 800g La 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 ＝1:49) And 2500g of cerium zirconium solid solution (ZrO 2 :CeO 2 :Pr 6 O 11 =27:70:3) adding 3000g of ionized water, uniformly mixing, ball milling, controlling the granularity to be 20 mu m, then dripping 20g of rhodium nitrate solution (containing 10 mass%Rh), uniformly stirring, adding 1g/L aluminum gel to prepare upper-layer coating slurry, coating the slurry on the semi-finished catalyst carrier prepared in the step (1) with the coating amount of 80g/L, quickly drying at 200 ℃, then programming the temperature of the catalyst to 500 ℃ at the temperature rising rate of 25 ℃/min, and roasting for 2 hours to obtain the finished catalyst.
Comparative example 1
A method for preparing a catalyst comprising the steps of:
(1) Coating of the lower layer coating: 30g of palladium nitrate solution (10 mass% Pd) was added to 50g of deionized water and then 500g of La was added dropwise 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:49), standing for 2 hours, drying in an oven at 100deg.C for 10 hours, programming the dried powder to 450deg.C at a heating rate of 15deg.C/min, calcining for 2 hours, pulverizing, and mixing with 500g cerium zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 =40:50:10) into water to prepare slurry, and ball milling to control the granularity to 15 μm; adding 100g of deionized water into 30g of ruthenium nitrate solution (containing 10 mass%Ru), diluting, adding 2g of polyvinylpyrrolidone, stirring for 2h, dripping into the slurry, stirring uniformly, adding 3g/L aluminum gel to prepare lower-layer coating slurry, coating the lower-layer coating slurry onto a carrier at a coating amount of 100g/L, rapidly drying at 150 ℃, then programming the temperature of the catalyst to 450 ℃ at a temperature rising rate of 15 ℃/min, and roasting for 1h to obtain a semi-finished product of the catalyst;
(2) Coating of an upper layer coating: 400g of La 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:49) and 1000g of cerium zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 Adding 2000g of ionized water, uniformly mixing, ball milling, controlling granularity to be 10 mu m, then dripping 10g of rhodium nitrate solution (containing 10 mass%Rh), uniformly stirring, adding 1g/L aluminum paste to prepare upper-layer coating slurry, and coating to the step with a coating amount of 70g/L(1) And (3) loading the prepared semi-finished catalyst on a carrier, quickly drying at 200 ℃, then programming the temperature of the catalyst to 600 ℃ at a temperature rising rate of 25 ℃/min, and roasting for 2 hours to obtain a finished catalyst product.
Comparative example 2
A method for preparing a catalyst comprising the steps of:
(1) Coating of the lower layer coating: 10g of palladium nitrate solution (10 mass% Pd) was added to 20g of deionized water and then 700g of La was added dropwise 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:24), standing for 2 hours, drying in a 100 ℃ oven for 12 hours, programming the dried powder to 550 ℃ at a heating rate of 15 ℃/min, roasting for 2 hours, crushing, and mixing with 600g of cerium-zirconium solid solution (ZrO 2 :CeO 2 :Y 2 O 3 =40:55:5) into water to prepare slurry, and ball milling to control the granularity to 15 μm; adding 100g of deionized water into 15g of barium nitrate, diluting, adding 1g of carboxymethyl cellulose, stirring for 4 hours, dripping into the slurry, stirring uniformly, adding 2g/L of aluminum gel to prepare lower-layer coating slurry, coating the lower-layer coating slurry on a carrier at a coating amount of 120g/L, rapidly drying at 150 ℃, then programming the temperature of the catalyst to 500 ℃ at a temperature rising rate of 15 ℃/min, and roasting for 1 hour to obtain a semi-finished product of the catalyst;
(2) Coating of an upper layer coating: 600g La 2 O 3 -Al 2 O 3 (La 2 O 3 :Al 2 O 3 =1:49) and 2000g of cerium zirconium solid solution (ZrO 2 :CeO 2 :Nd 2 O 3 =20:75:5) adding 3000g of ionized water, uniformly mixing, ball milling, controlling the granularity to be 11 mu m, then dripping 20g of rhodium nitrate solution (containing 10 mass%Rh), uniformly stirring, adding 1g/L aluminum gel to prepare upper-layer coating slurry, coating the slurry on the semi-finished catalyst carrier prepared in the step (1) with the coating amount of 70g/L, quickly drying at 200 ℃, then programming the temperature of the catalyst to 600 ℃ at the temperature rising rate of 25 ℃/min, and roasting for 2 hours to obtain the finished catalyst.
The catalyst samples obtained in examples 1 to 3 and comparative examples 1 to 2 were aged for 20 hours in a high temperature muffle furnace at 1050 ℃ under the same conditions, and then packaged as a purifier, and a whole vehicle emission test was performed according to a WLTC cycle, the engine displacement of the test vehicle was 1.6L, and the emission test results are shown in Table 1.
TABLE 1 comparison of catalytic Properties of the catalysts obtained in examples 1-3 and comparative examples 1-2
| THC(mg/km) | CO(mg/km) | NO X (mg/km) | |
| Example 1 | 25.6 | 205.7 | 35.9 |
| Example 2 | 36.9 | 218.6 | 42.3 |
| Example 3 | 21.3 | 189.5 | 29.1 |
| Comparative example 1 | 36.2 | 295.8 | 55.3 |
| Comparative example 2 | 28.5 | 207.4 | 37.6 |
Note that: THC in table 1 represents an abbreviation for the total amount of hydrocarbons contained in the gas.
As shown in Table 1, the results of the catalyst performance evaluation show that the catalysts prepared in examples 1 to 3 of the present invention have excellent exhaust gas purifying ability under various transient conditions, and exhibit better catalytic performance in terms of CO, HC and NOx conversion, as compared with comparative examples 1 to 2.
The catalyst of the invention comprises an upper coating layer and a lower coating layer, wherein noble metal Pd in the lower coating layer is supported on La 2 O 3 -Al 2 O 3 Noble metals Ru and barium salt are supported on La through dispersing agent 2 O 3 -Al 2 O 3 And cerium-zirconium solid solution, noble metal Rh in the upper coating layer is loaded on La 2 O 3 -Al 2 O 3 The invention enhances the purification capability of the tail gas of the internal combustion engine by adding Ru into the lower coating, enhances the deterioration resistance of Ru by Ba, reduces the dosage of Rh on the upper layer and reduces the cost of the whole catalyst.
Finally, it should be noted that the above-mentioned embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same, and although the present invention has been described in detail with reference to examples, it should be understood by those skilled in the art that modifications and equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention, and all such modifications and equivalents are intended to be encompassed in the scope of the claims of the present invention.
Claims (8)
1. A method for preparing a catalyst for enhancing the purification of the tail gas of an internal combustion engine is characterized in that the catalyst for enhancing the purification of the tail gas of the internal combustion engine comprises a carrier, a lower coating layer formed on the carrier and an upper coating layer formed on the lower coating layer, wherein the lower coating layer comprises a noble metal active component、La 2 O 3 -Al 2 O 3 Cerium zirconium solid solution and barium salt, the noble metal active component comprises noble metal Pd and noble metal Ru, and the noble metal Pd is loaded on La 2 O 3 -Al 2 O 3 On the above, the noble metal Ru and barium salt are dispersed by a dispersant and then loaded on La 2 O 3 -Al 2 O 3 And cerium zirconium solid solution; the upper coating comprises noble metal Rh, la 2 O 3 -Al 2 O 3 And cerium-zirconium solid solution, the noble metal Rh is supported on La 2 O 3 -Al 2 O 3 And cerium zirconium solid solution;
the preparation method comprises the following steps:
(1) And (2) coating the following coating: adding a certain amount of deionized water into Pd solution and then dripping La into the Pd solution 2 O 3 -Al 2 O 3 Standing for 0.5-5 h, then placing into a baking oven at 80-200 ℃ to dry for 4-12 h, programming the temperature of the dried powder to 350-600 ℃ at the temperature rising rate of 0.5-25 ℃/min, roasting for 1-8 h, crushing after roasting, adding the crushed powder and cerium-zirconium solid solution into water to prepare slurry, ball-milling the slurry, and controlling the granularity to be 7-20 mu m; mixing Ru solution and barium salt, adding deionized water for dilution, adding a dispersing agent for stirring for 0.5-8 hours, dripping into the ball-milled slurry, stirring uniformly, adding 1-5 g/L aluminum paste to prepare lower coating slurry, coating the lower coating slurry on a carrier in a coating amount of 50-200 g/L, drying at 100-250 ℃ for 5-10 minutes, and roasting to obtain a catalyst semi-finished product;
(2) Coating of an upper layer coating: la is subjected to 2 O 3 -Al 2 O 3 Adding cerium-zirconium solid solution into deionized water, uniformly mixing, ball milling, controlling granularity to be 7-20 mu m, dripping Rh solution into the slurry, uniformly stirring, adding 1-5 g/L aluminum paste to prepare coating slurry, coating the coating slurry on the semi-finished catalyst prepared in the step (1) with the coating amount of 50-200 g/L, drying at 100-250 ℃ for 5-10 min, then programming the temperature of the catalyst to 450-800 ℃ at the temperature rising rate of 0.5-25 ℃/min, and roasting for 1-8 h to obtain a catalyst finished product.
2. According to claimThe method for preparing the catalyst for enhancing the purification of the tail gas of the internal combustion engine, which is characterized in that: the loading capacity of the noble metal Pd in the lower coating is 5-250 g/ft 3 The loading capacity of the noble metal Ru in the lower coating is 5-100 g/ft 3 。
3. The method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine according to claim 1, wherein: the barium salt is selected from one or more of barium nitrate, barium acetate and barium sulfate, and the loading capacity of the barium salt in the lower coating is 1-50 g/ft 3 。
4. The method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine according to claim 1, wherein: the dispersing agent is one or more selected from polyvinyl alcohol, polyvinylpyrrolidone and carboxymethyl cellulose.
5. The method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine according to claim 1, wherein: the loading capacity of the noble metal Rh in the upper coating is 0.1-30 g/ft 3 。
6. The method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine according to claim 1, wherein: the La is 2 O 3 -Al 2 O 3 The components in the composition are as follows by mass percent: 1 to wt percent by weight to 10 percent by weight of La 2 O 3 And 90wt to 99wt% of Al 2 O 3 。
7. The method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine according to claim 1, wherein: the cerium-zirconium solid solution comprises the following components in percentage by mass: 20wt% -95wt% ZrO 2 、5wt%～80wt %CeO 2 And 0 to 10wt% of a composite oxide selected from La 2 O 3 、Y 2 O 3 、Pr 6 O 11 、Nd 2 O 3 One or more of them.
8. The method for preparing a catalyst for enhancing purification of exhaust gas of an internal combustion engine according to claim 1, wherein the roasting in the step (1) and the roasting in the step (2) are specifically: the catalyst is programmed to be heated to 450-800 ℃ at a heating rate of 0.5-25 ℃/min, and baked for 1-8 h.
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| CN114588901A (en) * | 2022-03-30 | 2022-06-07 | 北京工业大学 | NO oxidation catalyst for removing NOx from ship and preparation method thereof |
| CN114797851A (en) * | 2022-04-01 | 2022-07-29 | 中自环保科技股份有限公司 | Preparation method of catalyst with high CO purification performance and catalyst thereof |
| CN114700085B (en) * | 2022-05-07 | 2023-08-18 | 中自环保科技股份有限公司 | High-stability three-way catalyst and preparation method thereof |
| CN115920884B (en) * | 2022-11-03 | 2024-05-17 | 无锡威孚环保催化剂有限公司 | Three-way catalyst for reducing THC emission and preparation method thereof |
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