CN115805069B - Catalyst for diesel engine based on high-dispersion perovskite catalytic component and preparation method thereof - Google Patents
Catalyst for diesel engine based on high-dispersion perovskite catalytic component and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a diesel engine catalyst based on a high-dispersion perovskite catalytic component, which uses La x Ce 1‑x Mn y Bi 1‑y O 3 perovskite-MoO 3 The composite catalytic material nano particles are used as main catalytic active components and CeO is used as auxiliary material 2 、ZrO 2 、γ‑Al 2 O 3 Cordierite honeycomb ceramics. The catalyst is coated in the DOC, and can efficiently purify PM, HC, CO and other pollutants discharged by the diesel engine. The main catalytic active component has the advantages of sulfur resistance, heat resistance and low cost; the whole catalytic activity of the catalyst is enhanced by increasing the number of the catalytic active sites per unit mass, the complete replacement of noble metal is realized, and perovskite and MoO are contained in the catalyst 3 The simultaneous addition of (2) can produce a synergistic effect, further improve the catalytic activity of the catalyst and expand the high activity temperature window. The dispersion effect of the perovskite precursor is obviously improved by adopting the preparation of the carbon black adsorption matrix-based first adsorption and then gel, and the nano particles have smaller size, uniform particle size and regular structure.
Description
Technical Field
The invention belongs to the technology of purifying tail gas pollutants of an internal combustion engine for a vehicle, and particularly relates to an oxidation catalyst for purifying pollutants such as Particulate Matters (PM), hydrocarbon (HC), carbon monoxide (CO) and the like in diesel engine exhaust and a preparation method thereof.
Background
The diesel vehicle is the main force of heavy load, remote highway passenger and goods transportation at home and abroad, and makes excellent contribution to the development of national economy and the convenience of social life. However, due to the limitation of the combustion mode, the pollutant emission of the diesel vehicle is serious, so that most countries in the world are promoted to make increasingly severe emission regulations to limit the pollutant emission of the diesel vehicle, and the development and popularization of the exhaust pollutant control technology of the diesel engine for the vehicle are promoted. Among the numerous diesel exhaust gas pollutant control technologies, diesel Oxidation Catalysts (DOC) are effective technologies for reducing HC and CO emissions, and currently, DOC is almost an essential exhaust gas pollutant purifying device for automotive diesel engines. However, the traditional DOC needs to be coated with a catalytic coating taking noble metal as a main catalytic active component, and noble metal materials have poor performance in aspects of PM purification performance, sulfur poisoning resistance, heat aging resistance, coking resistance and the like, and the raw materials are high in price, so that the operation condition of modern advanced diesel engines is harsh, and the requirements on fuel oil and lubricating components are extremely severe, so that the reduction/substitution technology of the noble metal catalytic materials in the DOC has become a research hotspot at home and abroad.
The substituted perovskite and the transition metal oxide are all the most potential substitution materials for the noble metal catalytic material in the DOC, have excellent sulfur resistance, coking resistance and sintering resistance, are extremely low in raw material cost, have the purification characteristics of HC and CO similar to those of the noble metal catalytic material, and have lower purification efficiency of PM than the noble metal catalytic material. On the other hand, the whole catalytic activity of the catalytic material is enhanced, the reaction capacity of the catalytic active sites is improved, the number of the catalytic active sites is increased, an obvious effect can be obtained, the particle size of the catalytic active component particles in the catalyst is reduced, the specific surface area of the active component particles is increased, the exposure probability of the active component can be improved, and therefore the number of the catalytic active sites is possibly increased. Therefore, the preparation method of the high-dispersity ultrafine catalytic active component particles also becomes a core basic technology for popularization and application of substituted perovskite and transition metal oxides on DOCs, and at present, the technology is extremely vigorously researched at home and abroad.
Disclosure of Invention
Aiming at the prior art, the invention provides a catalyst for a diesel engine based on a high-dispersion perovskite catalytic component, which is simple and convenient to prepare and operate, saves preparation time and cost, can obviously improve the dispersion effect of a perovskite precursor, and is prepared by taking carbon black as an adsorption matrix and adopting the steps of adsorption and gel in the preparation process x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle templates, and methods of making same x Ce 1-x Mn y Bi 1-y O 3 La preparation by perovskite nanoparticle template x Ce 1-x Mn y Bi 1-y O 3 Perovskite-molybdenum oxide (MoO) 3 ) Composite catalytic material nanoparticle and La as described x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nano particles are used as main catalytic active components and CeO is used as catalyst active component 2 And ZrO(s) 2 As cocatalyst in gamma-Al 2 O 3 Is a coating auxiliary material.
In order to solve the technical problems, the catalyst for the diesel engine based on the high-dispersion perovskite catalytic component provided by the invention comprises a catalytic coating coated on a carrier, wherein the carrier is 400-mesh cordierite honeycomb ceramic, and the catalytic coating consists of a main catalytic active component, a cocatalyst and a coating auxiliary material; the catalyst promoter is composed of CeO 2 And ZrO(s) 2 The coating auxiliary material consists of gamma-Al 2 O 3 Composition; the main catalytic active component is formed by ABO 3 perovskite-MoO 3 Composite catalytic material nanoparticle composition, wherein, ABO 3 Perovskite and MoO 3 The mass percentage of (a) is 60-90%/40-10%, ABO 3 Perovskite and MoO 3 The sum of the mass percentages of the components is 100 percent; the ABO 3 The A site of perovskite is composed of La and Ce, the B site is composed of Mn and Bi, la is formed x Ce 1-x Mn y Bi 1-y O 3 A perovskite type, wherein x represents the mole percentage ratio of La at the A position in the sum of the mole numbers of Ce and La at the A position, and x=60-90%; y represents the mole percentage ratio of Mn at the B site in the sum of the mole numbers of Mn and Bi at the B site, and y=50-80%; at the same time, the La x Ce 1-x Mn y Bi 1-y O 3 The ratio of the sum of the mole numbers of La ions and Ce ions to the sum of the mole numbers of Mn ions and Bi ions in the perovskite is 1:1; the La is x Ce 1-x Mn y Bi 1-y O 3 The role of the perovskite in the catalyst is not only one component of the main catalytic active ingredient, but also the preparation of La x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Nanoparticle templates of composite catalytic material nanoparticles.
Further, the catalyst for diesel engine based on the highly dispersed perovskite catalytic component according to the present invention, wherein:
in the cocatalyst, the CeO 2 And ZrO(s) 2 The mass percentage of the catalyst is 70-90%/10-30%, and the sum of the mass percentages of the catalyst and the catalyst is 100%.
Said gamma-Al 2 O 3 Comprising gamma-Al derived from pure material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The pure gamma-Al 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 80-90%/10-20%, the sum of the mass percentages of the two is 100%.
The mass percentage of the main catalytic active component, the cocatalyst and the coating auxiliary material is 1-5%/4-10%/85-95%, and the sum of the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material is 100%.
The mass percentage of the catalytic coating and the carrier is 15-30%/85-70%, and the sum of the mass percentages of the catalytic coating and the carrier is 100%.
The invention provides a preparation method of the diesel engine catalyst based on the high-dispersion perovskite catalytic component, which comprises the following steps:
step 1, designing a catalyst composition: according to the proportions of the components, the following proportions are respectively designed: la in main catalytic active ingredient x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 In mass percent of La x Ce 1-x Mn y Bi 1-y O 3 Mole percent of La element and Ce element in perovskite, mole percent of Mn element and Bi element, and CeO in cocatalyst 2 And ZrO(s) 2 In mass percent of gamma-Al 2 O 3 Pure gamma-Al in coating auxiliary material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of the main catalytic active component, the cocatalyst and the coating auxiliary material, and the mass of the catalytic coating which can be generated by planning to configure the coating slurry;
step 2, la x Ce 1-x Mn y Bi 1-y O 3 Preparing a perovskite nanoparticle template: calculating La in the main catalytic active component according to the proportion of each component designed in the step 1 and the quality of the catalytic coating which can be generated by planning to configure coating slurry x Ce 1- x Mn y Bi 1-y O 3 Quality of perovskite nanoparticle template and La x Ce 1-x Mn y Bi 1-y O 3 The mole number of La, ce, mn and Bi elements in the perovskite nano particle template;
bind to each 433.0g La (NO) 3 ) 3 ·6H 2 O preparation of 1mol La, per 434.1g Ce (NO) 3 ) 3 ·6H 2 O preparation of 1mol Ce per 173.0g Mn (CH) 3 COO) 2 Preparation of 1mol Mn per 485.1g Bi (NO 3 ) 3 ·5H 2 O preparation of 1mol Bi and La x Ce 1-x Mn y Bi 1-y O 3 The La is prepared by calculating the conversion ratio of the sum of the mole numbers of La, ce, mn and Bi elements in the perovskite nanoparticle template to the mole number of glucose used to be 1:1-2 and the weight of 180.2g per mole of glucose x Ce 1-x Mn y Bi 1-y O 3 La (NO) for perovskite nanoparticle templates 3 ) 3 ·6H 2 O、Ce(NO 3 ) 3 ·6H 2 O、Mn(CH 3 COO) 2 、Bi(NO 3 ) 3 ·5H 2 Mass of O and glucose; weighing La (NO) of determined mass 3 ) 3 ·6H 2 O、Ce(NO 3 ) 3 ·6H 2 O、Mn(CH 3 COO) 2 、Bi(NO 3 ) 3 ·5H 2 O, glucose and a mass of La (NO) 3 ) 3 ·6H 2 O、Ce(NO 3 ) 3 ·6H 2 O、Mn(CH 3 COO) 2 Bi (NO) 3 ) 3 ·5H 2 In the range of 0.8 to 1.5 times the sum of O masses and D 50 Adding the 6 raw materials into deionized water which is weighed according to the proportion of 1g of carbon black to 30-50 mL of deionized water together, oscillating for 6-8 hours by ultrasonic wave, and then adding the mixture into the deionized water after the mixture is superHeating the mixture of the 6 raw materials and deionized water while oscillating by sound waves, so that the mixture is evaporated to dryness after 6-8 hours to form wet gel; drying the wet gel at 80-110 ℃ for 6-12 hours to obtain xerogel; heating the xerogel to 400 ℃ in a muffle furnace at a speed of 3 ℃/min and keeping for 2 hours, heating to 700-800 ℃ at a speed of 10 ℃/min, and calcining for 3-4 hours to obtain La x Ce 1-x Mn y Bi 1-y O 3 A perovskite nanoparticle template;
step 3, preparing main catalytic active components: calculating MoO in the main catalytic active component according to the proportion of each component designed in the step 1 and the quality of the catalytic coating which can be generated by planning to configure coating slurry 3 Is the mass of (3);
combined with each 196.0g (NH) 4 ) 2 MoO 4 Preparation of 144.0g MoO 3 The conversion ratio of (C) to (C) is calculated to obtain the (NH) required for the preparation of the main catalyst active ingredient 4 ) 2 MoO 4 Is the mass of (3); weighing the (NH) 4 ) 2 MoO 4 La obtained by the preparation of step 2 x Ce 1-x Mn y Bi 1-y O 3 A perovskite nanoparticle template, and the (NH 4 ) 2 MoO 4 And La (La) x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle template addition was performed according to 1g (NH 4 ) 2 MoO 4 In the deionized water which is weighed according to the proportion of 50-500 ml of deionized water, carrying out ultrasonic oscillation to form slurry; by NaOH or HNO 3 Adjusting the pH of the slurry to a pH in the range of 4 to 6 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is heated while ultrasonic oscillation is carried out, so that the slurry is evaporated to dryness after 4-8 hours and becomes solid; drying the evaporated solid at 80-110 ℃ for 6-12 h, presintering at 350 ℃ for 2h, calcining at 500-550 ℃ for 2-3 h, and obtaining powdery and massive solid La x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic materialThe material nano particles are the main catalytic active components of the catalyst;
step 4, preparing coating slurry: calculating CeO required for preparing the catalytic coating according to the proportions of the components designed in the step 1 and the quality of the catalytic coating which can be generated by planning to configure the coating slurry 2 And ZrO(s) 2 Quality of (C) and gamma-Al 2 O 3 The quality of the coating auxiliary materials;
bind per 434.2g Ce (NO) 3 ) 3 ·6H 2 O preparation 172.1g CeO 2 Each 429.3g of Zr (NO) 3 ) 4 ·5H 2 O preparation 123.2g ZrO 2 Al in aluminum sol 2 O 3 Calculated out the mass percent of Ce (NO) required for preparing the coating slurry 3 ) 3 ·6H 2 O、Zr(NO 3 ) 4 ·5H 2 O and the mass of the aluminum sol; in addition, the mass of polyethylene glycol consumed for preparing the catalytic coating is calculated according to the proportion of 5-15 g of polyethylene glycol with average molecular weight of 20000 required for each 100g of the catalytic coating; weighing Ce (NO) with determined mass 3 ) 3 ·6H 2 O、Zr(NO 3 ) 4 ·5H 2 O, pure gamma-Al 2 O 3 Powder, aluminum sol, polyethylene glycol with molecular weight of 20000 and La prepared in step 3 x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The 6 raw materials are added into deionized water with the mass 5-15 times of the mass of the catalytic coating to be prepared together to form slurry by ultrasonic oscillation; by NaOH or HNO 3 Adjusting the pH of the slurry to a value in the range of 5 to 7 and grinding the slurry on a grinder to D 50 The grain diameter is in the range of 800-1000 nm, and the ground slurry is stirred for 48-72 h at the temperature of 50-70 ℃ to obtain coating slurry;
step 5, coating a catalytic coating on the carrier: designing the quality of the support to which the catalytic coating is to be applied; weighing the carrier with determined mass, immersing the carrier in the coating slurry at 50-70 ℃ and ensuring that the upper end surface of the carrier is slightly higher than the slurry level; after the slurry naturally lifts all pore canals filled with the carrier, the carrier is taken out from the slurry, residual fluid in the pore canals is blown off, the slurry is dried for 4 to 16 hours at the temperature of 80 to 110 ℃, and then the slurry is baked for 2 to 4 hours at the temperature of 500 to 600 ℃; repeating the processes of dipping, drying and roasting for 2-3 times to obtain the catalyst for the diesel engine based on the high-dispersion perovskite catalytic component.
The diesel engine catalyst based on the high-dispersion perovskite catalytic component prepared by the method is packaged into a diesel engine oxidation catalyst (DOC), and the diesel engine oxidation catalyst is arranged in an exhaust passage of a diesel engine to realize efficient oxidation and purification of PM, HC and CO in exhaust gas of the diesel engine.
Compared with the prior art, the invention has the beneficial effects that:
the preparation method of the first adsorption and then gel based on the carbon black adsorption matrix is simple and convenient to operate, saves the preparation time and the cost, can obviously improve the dispersion effect of the perovskite precursor, and is beneficial to preparing La with smaller scale, uniform particle size and regular structure x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticles of the type. And by La x Ce 1-x Mn y Bi 1-y O 3 As the superfine particle template, the perovskite nano-particles can be used for further preparing La with high dispersity x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nanoparticles. La (La) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The composite catalytic material nanoparticle main catalytic active component has the advantages of sulfur resistance, coking resistance, heat resistance and low cost, and can obviously increase the number of catalytic active sites per unit mass and improve the catalytic activity of the catalytic active sites, so that the integral pollutant purification performance of the DOC is improved, the complete replacement of noble metal materials in the DOC is realized, and the raw material cost of the catalyst is obviously reduced. In addition, la x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 La in nano-particle main catalytic active component of composite catalytic material x Ce 1-x Mn y Bi 1-y O 3 Calcium titaniumOre and MoO 3 The simultaneous addition of the catalyst can generate a synergistic effect, so that the overall catalytic activity of the catalyst is further improved, and a high-activity temperature window is expanded.
Drawings
Fig. 1 is a schematic diagram of an engine evaluation system for purifying PM, HC and CO in exhaust gas of a diesel engine.
Wherein: 1-a dynamometer; a 2-coupling; 3-testing a diesel engine; 4-an intake air flow meter; 5-an intake air processor; 6-an oil injector; 7-a fuel injection control system; 8-an exhaust sampling port A; 9-a temperature sensor a; a 10-Diesel Oxidation Catalyst (DOC); 11-a temperature sensor B; 12-an exhaust sampling port B; 13-a selective catalytic reduction catalyst; 14-diesel particulate trap; 15-an exhaust sampling mechanism; 16-engine exhaust gas analyzer; 17-an exhaust gas filter; 18-an air pump.
FIG. 2 shows an engine evaluation system for purifying PM, HC, and CO in the exhaust gas of the diesel engine, wherein the exhaust gas temperature of the diesel engine is 300 ℃ and the airspeed of the engine is 50000h -1 In this case, the catalysts described in examples 1 to 3 were effective in purifying PM, HC, and CO in the exhaust gas of diesel engine.
FIG. 3 shows an engine evaluation system for purifying PM, HC, and CO in the exhaust gas of the diesel engine, wherein the exhaust gas temperature of the diesel engine is 400 ℃ and the airspeed is 100000h -1 In this case, the catalysts described in examples 1 to 3 were effective in purifying PM, HC, and CO in the exhaust gas of diesel engine.
Fig. 4 shows the purification performance of PM, HC and CO in the diesel exhaust gas by the catalyst described in examples 1 to 3 in the european steady state test cycle (ESC) test by using the diesel exhaust gas PM, HC and CO purification performance engine evaluation system.
Detailed Description
The invention will now be further described with reference to the accompanying drawings and specific examples, which are in no way limiting.
The invention relates to a catalyst for a diesel engine based on a high-dispersion perovskite catalytic component, which comprises a catalytic coating coated on a carrier, wherein the carrier is 400-mesh cordierite honeycomb ceramics, and the catalytic coating consists of a main catalytic active component, a cocatalyst and a coating auxiliary material; the cocatalyst is CeO 2 And ZrO(s) 2 The coating auxiliary material consists of gamma-Al 2 O 3 The composition comprises the following components in percentage by weight:
(1) By La of x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The composite catalytic material nano particles are main catalytic active components, and the La x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 The mass percentage of (3) is as follows: 60-90%/40-10%, the sum of the mass percentages is 100%.
(2) The La is x Ce 1-x Mn y Bi 1-y O 3 In the perovskite type, the mole percentages of La element and Ce element are as follows: 60-90%/10-40%, the sum of the mole percentages is 100%; the mole percentages of Mn element and Bi element are: 50-80%/20-50%, the sum of the mole percentages is 100%; and the sum of the mole numbers of La element and Ce element is equal to the sum of the mole numbers of Mn element and Bi element; the La is x Ce 1-x Mn y Bi 1-y O 3 The role of the perovskite in the catalyst is not only one component of the main catalytic active ingredient, but also the preparation of La x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Nanoparticle templates of composite catalytic material nanoparticles.
(3) With CeO 2 And ZrO(s) 2 Is a cocatalyst, and the CeO 2 And ZrO(s) 2 The mass percentage of (3) is as follows: 70-90%/10-30%, the sum of the mass percentages is 100%.
(4) By gamma-Al 2 O 3 Is a coating auxiliary material, and the gamma-Al 2 O 3 Respectively from pure gamma-Al 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The pure gamma-Al 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 80-90%/10-20%, the sum of the mass percentages is 100%.
(5) The main catalytic active component, the cocatalyst and the coating auxiliary material form a catalytic coating of the catalyst, and the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material are as follows: 1-5%/4-10%/85-95%, the sum of the mass percentages is 100%.
(6) The catalyst of the invention is composed of the catalytic coating and 400-mesh cordierite honeycomb ceramics, wherein the 400-mesh cordierite honeycomb ceramics are carriers of the catalyst of the invention, the catalytic coating is required to be coated on the carriers, and the mass percentage range of the catalytic coating and the carriers is as follows: 15-30%/85-70%, the sum of the mass percentages is 100%.
The catalyst for diesel engine based on the high-dispersion perovskite catalytic component is suitable for purifying PM, HC and CO in the exhaust gas of the diesel engine, and adopts La prepared by taking carbon black as an adsorption matrix and adopting the steps of adsorption and then gelation x Ce 1- x Mn y Bi 1-y O 3 Perovskite nanoparticles, and methods of making same x Ce 1-x Mn y Bi 1-y O 3 La preparation by taking perovskite nano-particles as templates x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nanoparticle and La as described x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nano particles are used as main catalytic active components and CeO is used as catalyst active component 2 And ZrO(s) 2 As cocatalyst in gamma-Al 2 O 3 The specific process mainly comprises the following 5 steps of:
(1) The catalyst composition is designed;
(2)La x Ce 1-x Mn y Bi 1-y O 3 preparing a perovskite nanoparticle template;
(3) Preparing main catalytic active components;
(4) Preparing coating slurry;
(5) A catalytic coating is applied to the support.
The technical scheme of the invention is further described below through specific embodiments and with reference to the accompanying drawings. It should be noted that the examples are illustrative and not limiting, and the invention is not limited to the examples.
A catalyst for diesel engines based on a highly dispersed perovskite catalytic component comprises: la (La) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nano particles and CeO 2 、ZrO 2 、γ-Al 2 O 3 400 mesh cordierite honeycomb ceramics.
By La of x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The composite catalytic material nano particles are main catalytic active components, and the La x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 The mass percentage of (3) is as follows: 60-90%/40-10%, the sum of the mass percentages is 100%.
The La is x Ce 1-x Mn y Bi 1-y O 3 In the perovskite type, the mole percentages of La element and Ce element are as follows: 60-90%/10-40%, the sum of the mole percentages is 100%; the mole percentages of Mn element and Bi element are: 50-80%/20-50%, the sum of the mole percentages is 100%; and the sum of the mole numbers of La element and Ce element is equal to the sum of the mole numbers of Mn element and Bi element; the La is x Ce 1-x Mn y Bi 1-y O 3 The role of the perovskite in the catalyst is not only one component of the main catalytic active ingredient, but also the preparation of La x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Nanoparticle templates of composite catalytic material nanoparticles.
With CeO 2 And ZrO(s) 2 Is a cocatalyst, and the CeO 2 And ZrO(s) 2 The mass percentage of (3) is as follows: 70-90%/10-30%, the sum of the mass percentages is 100%.
By gamma-Al 2 O 3 Is a coating auxiliary material, and the gamma-Al 2 O 3 Respectively from pure gamma-Al 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The saidPure gamma-Al 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 80-90%/10-20%, the sum of the mass percentages is 100%.
The main catalytic active component, the cocatalyst and the coating auxiliary material form a catalytic coating of the catalyst, and the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material are as follows: 1-5%/4-10%/85-95%, the sum of the mass percentages is 100%.
The catalyst of the invention is composed of the catalytic coating and 400-mesh cordierite honeycomb ceramics, wherein the 400-mesh cordierite honeycomb ceramics are carriers of the catalyst of the invention, the catalytic coating is required to be coated on the carriers, and the mass percentage range of the catalytic coating and the carriers is as follows: 15-30%/85-70%, the sum of the mass percentages is 100%.
The preparation method of the catalyst of the present invention is described in detail below by way of specific examples.
Example 1
(1) Catalyst composition design
The following proportions are respectively designed: la (La) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 La in composite catalytic material nano-particles x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 The mass percentage of (3) is as follows: 90%/10%, la x Ce 1-x Mn y Bi 1-y O 3 The mole percentages of La element and Ce element in the perovskite are as follows: 60%/40%, and mole percentages of Mn element and Bi element are: 50%/50%, ceO in Co-catalyst 2 And ZrO(s) 2 The mass percentage of (3) is as follows: 70%/30%, gamma-Al 2 O 3 Pure gamma-Al in coating auxiliary material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 80%/20%, the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material are as follows: 1%/4%/95% and the coating slurry is intended to produce 2000g of catalytic coating.
(2)La x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle template preparation
14.6g La (NO) was weighed out 3 ) 3 ·6H 2 O、9.8g Ce(NO 3 ) 3 ·6H 2 O、4.9g Mn(CH 3 COO) 2 、13.7g Bi(NO 3 ) 3 ·5H 2 O, 40g of glucose and 60g of median particle diameter (D 50 Particle size) of 452nm, adding the 6 raw materials into 3L of deionized water, carrying out ultrasonic oscillation for 6 hours, and then heating a mixture of the 6 raw materials and the deionized water while carrying out ultrasonic oscillation, so that the mixture is evaporated to dryness after 8 hours to form wet gel; drying the wet gel at 80 ℃ for 12 hours to obtain xerogel; heating the xerogel to 400 ℃ in a muffle furnace at a speed of 3 ℃/min and keeping for 2 hours, and then heating to 800 ℃ at a speed of 10 ℃/min and calcining for 3 hours to obtain La x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle templates.
(3) Preparation of main catalytic active ingredient
Weigh 2.7g (NH) 4 ) 2 MoO 4 And La obtained by the preparation in the step (2) x Ce 1-x Mn y Bi 1-y O 3 Adding the 2 raw materials into 1350ml deionized water, and carrying out ultrasonic oscillation to form slurry; by NaOH or HNO 3 Adjusting the pH of the slurry to a pH in the range of 4 to 6 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is heated while oscillating with ultrasonic waves, so that the slurry is evaporated to dryness after 8 hours and becomes a solid. Drying the evaporated solid at 80 ℃ for 12 hours, presintering at 350 ℃ for 2 hours, and calcining at 500 ℃ for 3 hours to obtain powdery and massive solid. The powdery and massive solids obtained after the calcination are La x Ce 1-x Mn y Bi 1- y O 3 perovskite-MoO 3 Composite catalytic material nanoparticles.
(4) Preparation of coating slurry
141.3g Ce (NO) was weighed out 3 ) 3 ·6H 2 O、83.6g Zr(NO 3 ) 4 ·5H 2 O, 1520g of pure gamma-Al 2 O 3 Powder, 1900g Al 2 O 3 20% of aluminum sol, 300g of polyethylene glycol with molecular weight of 20000 and La prepared in step (3) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The 6 raw materials are added into 10kg of deionized water together to form slurry by ultrasonic oscillation; by NaOH or HNO 3 Adjusting the pH of the slurry to a value in the range of 5 to 7 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is stirred for 48 hours at 70 ℃ to obtain the coating slurry.
(5) Applying a catalytic coating to a support
Weighing 1kg of the carrier, immersing the carrier in the coating slurry at 70 ℃ and ensuring that the upper end surface of the carrier is slightly higher than the liquid level of the slurry; and taking the carrier out of the slurry after the slurry naturally lifts all the pore channels filled with the carrier, blowing off residual fluid in the pore channels, drying for 4 hours at 110 ℃, and roasting for 4 hours at 500 ℃. Repeating the above processes of dipping, drying and roasting for 3 times to obtain the catalyst for diesel engine based on the high-dispersion perovskite catalytic component.
Example 2
(1) Catalyst composition design
The following proportions are respectively designed: la (La) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 La in composite catalytic material nano-particles x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 The mass percentage of (3) is as follows: 60%/40%, la x Ce 1-x Mn y Bi 1-y O 3 The mole percentages of La element and Ce element in the perovskite are as follows: 90%/10%, and mole percentages of Mn element and Bi element are: 80%/20%, ceO in cocatalyst 2 And ZrO(s) 2 Is of mass percent of (a)The ratio is as follows: 90%/10%, gamma-Al 2 O 3 Pure gamma-Al in coating auxiliary material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 90%/10%, the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material are as follows: 5%/10%/85% and the coating slurry is intended to produce 2000g of catalytic coating.
(2)La x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle template preparation
Weigh 85.7g La (NO) 3 ) 3 ·6H 2 O、9.6g Ce(NO 3 ) 3 ·6H 2 O、30.4g Mn(CH 3 COO) 2 、21.3g Bi(NO 3 ) 3 ·5H 2 O, 80g of glucose, and 120g of median particle diameter (D 50 Particle size) of 373nm, adding the 6 raw materials into 3.6L of deionized water, oscillating for 8 hours by ultrasonic waves, and then heating a mixture of the 6 raw materials and the deionized water while oscillating by ultrasonic waves, so that the mixture is evaporated to dryness after 6 hours to form wet gel; drying the wet gel at 80 ℃ for 12 hours to obtain xerogel; heating the xerogel to 400 ℃ in a muffle furnace at a speed of 3 ℃/min and keeping for 2 hours, and then heating to 700 ℃ at a speed of 10 ℃/min and calcining for 4 hours to obtain La x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle templates.
(3) Preparation of main catalytic active ingredient
Weighing 54.4g (NH) 4 ) 2 MoO 4 And La obtained by the preparation in the step (2) x Ce 1-x Mn y Bi 1-y O 3 Adding the 2 raw materials into 3000ml deionized water, and carrying out ultrasonic oscillation to form slurry; by NaOH or HNO 3 Adjusting the pH of the slurry to a pH in the range of 4 to 6 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is heated while oscillating with ultrasonic waves, so that the slurry is evaporated to dryness after 4 hours and becomes a solid. Will beThe evaporated solid is dried for 6 hours at 110 ℃, presintered for 2 hours at 350 ℃ and calcined for 2 hours at 550 ℃ to form powdery and massive solid. The powdery and massive solids obtained after the calcination are La x Ce 1- x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nanoparticles.
(4) Preparation of coating slurry
454.1g Ce (NO) was weighed out 3 ) 3 ·6H 2 O、69.7g Zr(NO 3 ) 4 ·5H 2 O, 1530g of pure gamma-Al 2 O 3 Powder, 850g Al 2 O 3 20% of aluminum sol, 100g of polyethylene glycol with molecular weight of 20000 and La prepared in step (3) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The 6 raw materials are added into 30kg of deionized water together to form slurry by ultrasonic oscillation; by NaOH or HNO 3 Adjusting the pH of the slurry to a value in the range of 5 to 7 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is stirred for 72 hours at 50 ℃ to obtain the coating slurry.
(5) Applying a catalytic coating to a support
Weighing 1kg of the carrier, immersing the carrier in the coating slurry at 50 ℃ and ensuring that the upper end surface of the carrier is slightly higher than the liquid level of the slurry; and taking the carrier out of the slurry after the slurry naturally lifts all the pore channels filled with the carrier, blowing off residual fluid in the pore channels, drying at 80 ℃ for 16h, and roasting at 600 ℃ for 2h. Repeating the above processes of dipping, drying and roasting for 2 times to obtain the catalyst for diesel engine based on the high-dispersion perovskite catalytic component.
Example 3
(1) Catalyst composition design
The following proportions are respectively designed: la (La) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 La in composite catalytic material nano-particles x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 The mass percentage of (3) is as follows: 80%/20%, la x Ce 1-x Mn y Bi 1-y O 3 The mole percentages of La element and Ce element in the perovskite are as follows: 80%/20%, and mole percentages of Mn element and Bi element are: 60%/40%, ceO in cocatalyst 2 And ZrO(s) 2 The mass percentage of (3) is as follows: 80%/20%, gamma-Al 2 O 3 Pure gamma-Al in coating auxiliary material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 80%/20%, the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material are as follows: 3%/7%/90% and the coating slurry is intended to produce 2000g of catalytic coating.
(2)La x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle template preparation
Weighing 54.7g La (NO) 3 ) 3 ·6H 2 O、13.7g Ce(NO 3 ) 3 ·6H 2 O、16.4g Mn(CH 3 COO) 2 、30.7g Bi(NO 3 ) 3 ·5H 2 O, 60g of glucose, and 120g of median particle diameter (D 50 Particle size) of 373nm, adding the 6 raw materials into 4.8L of deionized water, oscillating for 7 hours by ultrasonic waves, and then heating a mixture of the 6 raw materials and the deionized water while oscillating by ultrasonic waves, so that the mixture is evaporated to dryness after 7 hours to form wet gel; drying the wet gel at 80 ℃ for 12 hours to obtain xerogel; heating the xerogel to 400 ℃ in a muffle furnace at a speed of 3 ℃/min and keeping for 2 hours, and then heating to 800 ℃ at a speed of 10 ℃/min and calcining for 3 hours to obtain La x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle templates.
(3) Preparation of main catalytic active ingredient
16.3g (NH) 4 ) 2 MoO 4 And La obtained by the preparation in the step (2) x Ce 1-x Mn y Bi 1-y O 3 Perovskite nano-meterAdding the 2 raw materials into 1600ml of deionized water, and carrying out ultrasonic oscillation to form slurry; by NaOH or HNO 3 Adjusting the pH of the slurry to a pH in the range of 4 to 6 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is heated while oscillating with ultrasonic waves, so that the slurry is evaporated to dryness after 6 hours and becomes a solid. Drying the evaporated solid at 100 ℃ for 8 hours, presintering at 350 ℃ for 2 hours, and calcining at 550 ℃ for 2 hours to obtain powdery and massive solid. The powdery and massive solids obtained after the calcination are La x Ce 1- x Mn y Bi 1-y O 3 perovskite-MoO 3 Composite catalytic material nanoparticles.
(4) Preparation of coating slurry
282.6g Ce (NO) was weighed 3 ) 3 ·6H 2 O、97.6g Zr(NO 3 ) 4 ·5H 2 1440g of pure gamma-Al 2 O 3 Powder, 1800g of Al 2 O 3 20% of aluminum sol, 200g of polyethylene glycol with molecular weight of 20000 and La prepared in step (3) x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The 6 raw materials are added into 20kg of deionized water together to form slurry by ultrasonic oscillation; by NaOH or HNO 3 Adjusting the pH of the slurry to a value in the range of 5 to 7 and grinding the slurry on a grinder to D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is stirred for 60 hours at the temperature of 60 ℃ to obtain the coating slurry.
(5) Applying a catalytic coating to a support
Weighing 1kg of the carrier, immersing the carrier in the coating slurry at 60 ℃ and ensuring that the upper end surface of the carrier is slightly higher than the liquid level of the slurry; and taking the carrier out of the slurry after the slurry naturally lifts all the pore channels filled with the carrier, blowing off residual fluid in the pore channels, drying at 100 ℃ for 8h, and roasting at 550 ℃ for 3h. Repeating the above processes of dipping, drying and roasting for 3 times to obtain the catalyst for diesel engine based on the high-dispersion perovskite catalytic component.
The diesel exhaust PM, HC and CO purification performance of the catalysts prepared in examples 1 to 3 was evaluated by using the diesel exhaust PM, HC and CO purification performance engine evaluation system shown in fig. 1. The catalysts prepared in examples 1-3 were cut separately and combined into monolithic catalysts, and the cut and combined monolithic catalysts were subjected to encapsulation treatment before the test. The test method comprises the following steps:
(1) Steady state condition test: the torque and the rotating speed of the test engine 3 are controlled by using the dynamometer 1 and the coupler 2, the oil supply speed of the oil injector 6 to the diesel engine is regulated by the fuel injection control system 7, and the ratio of the exhaust flow of the engine to the volume of the catalyst is controlled to be 50000h respectively -1 And 100000h -1 And the average temperatures of the exhaust gas in the Diesel Oxidation Catalyst (DOC) 10 are controlled to be 300 ℃ and 400 ℃ respectively, and PM, HC and CO purification performance evaluation is performed. The intake air flow measurement of the intake air flow meter 4 provides feedback parameters for the control strategy of the fuel injection control system; while the intake air processor 5 provides clean air of a specific temperature, humidity to the engine. The temperature sensor A9 and the temperature sensor B11 respectively measure the exhaust temperatures at two ends of the DOC10, and the average temperature of the exhaust in the DOC10 can be obtained by obtaining the average value of the two temperatures. The exhaust samples before and after the DOC10 treatment respectively enter the exhaust sampling mechanism 15 and the engine exhaust analyzer 16 through the exhaust sampling port A8 and the exhaust sampling port B12 to analyze the specific discharge amounts of PM, HC and CO, and the exhaust after the exhaust component analysis is discharged out of the laboratory through the air pump 18 after purifying the particulate pollutants through the exhaust gas filter 17. Meanwhile, after the sampled residual exhaust gas of the test engine 3 is subjected to exhaust gas purification through the selective catalytic reduction catalyst 13 and the diesel particulate filter 14 in sequence, particulate pollutants are purified through the exhaust gas filter 17, and then the particulate pollutants are discharged out of a laboratory through the air pump 18. By using the engine evaluation system for purifying PM, HC and CO of the diesel exhaust, the average exhaust temperature in DOC is 300 ℃ and the airspeed is 50000h -1 When the average exhaust temperature in DOC is 400 ℃ and the airspeed is 100000h -1 Examples 1 to 3 were obtainedThe purification efficiency of the prepared catalyst for diesel exhaust PM, HC and CO is shown in fig. 2 and 3, respectively.
(2) ESC test: the purification performance engine evaluation system of PM, HC and CO of the diesel exhaust is adopted, and the purification effect of the catalyst prepared in examples 1-3 on PM, HC and CO of the diesel exhaust is evaluated according to ESC test rules regulated in national standard GB 17691-2005 (compression ignition for vehicle, gas Fuel ignition engine and exhaust pollutant emission Limit and measurement method (China III, IV, V phase)) as shown in FIG. 4.
In conclusion, the catalyst prepared by the invention can be coated in the DOC, so that pollutants such as PM, HC and CO discharged by a diesel engine can be purified efficiently. The composite catalytic material nanoparticle main catalytic active component has the advantages of sulfur resistance, heat resistance and low cost, enhances the overall catalytic activity of the catalyst by increasing the number of catalytic active sites per unit mass, realizes the complete replacement of noble metals, and realizes the complete replacement of perovskite and MoO 3 The simultaneous addition of (2) can produce a synergistic effect, further improve the catalytic activity of the catalyst and expand the high activity temperature window. The preparation method of the carbon black adsorption matrix-based pre-adsorption and re-gelation obviously improves the dispersion effect of the perovskite precursor, and is beneficial to preparing composite catalytic material nano particles with smaller scale, uniform particle size and regular structure.
Although the invention has been described above with reference to the accompanying drawings, the invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many changes may be made by those skilled in the art without departing from the spirit of the invention, which are all within the protection of the invention.
Claims (7)
1. The catalyst for the diesel engine based on the high-dispersion perovskite catalytic component comprises a catalytic coating coated on a carrier, wherein the carrier is 400-mesh cordierite honeycomb ceramic, and the catalytic coating consists of a main catalytic active component, a cocatalyst and a coating auxiliary material; the catalyst promoter is composed of CeO 2 And ZrO(s) 2 The coating auxiliary material consists of gamma-Al 2 O 3 Composition; the method is characterized in that:
the main catalytic active component is formed by ABO 3 perovskite-MoO 3 Composite catalytic material nanoparticle composition, wherein, ABO 3 Perovskite and MoO 3 The mass percentage of (a) is 60-90%/40-10%, ABO 3 Perovskite and MoO 3 The sum of the mass percentages of the components is 100 percent;
the ABO 3 The A site of perovskite is composed of La and Ce, the B site is composed of Mn and Bi, la is formed x Ce 1-x Mn y Bi 1-y O 3 A perovskite type, wherein x represents the mole percentage ratio of La at the A position in the sum of the mole numbers of Ce and La at the A position, and x=60-90%; y represents the mole percentage ratio of Mn at the B site in the sum of the mole numbers of Mn and Bi at the B site, and y=50-80%; at the same time, the La x Ce 1-x Mn y Bi 1-y O 3 The ratio of the sum of the mole numbers of La ions and Ce ions to the sum of the mole numbers of Mn ions and Bi ions in the perovskite is 1:1; the La is x Ce 1-x Mn y Bi 1-y O 3 The role of the perovskite in the catalyst is not only one component of the main catalytic active ingredient, but also the preparation of La x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 Nanoparticle templates of composite catalytic material nanoparticles.
2. The catalyst for diesel engine based on highly dispersed perovskite catalytic component as claimed in claim 1, wherein: in the cocatalyst, the CeO 2 And ZrO(s) 2 The mass percentage of the catalyst is 70-90%/10-30%, and the sum of the mass percentages of the catalyst and the catalyst is 100%.
3. The catalyst for diesel engine based on highly dispersed perovskite catalytic component as claimed in claim 1, wherein: said gamma-Al 2 O 3 Comprising gamma-Al derived from pure material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The pure gamma-Al 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of (3) is as follows: 80-90%/10-20%, the sum of the mass percentages of the two is 100%.
4. The catalyst for diesel engine based on highly dispersed perovskite catalytic component as claimed in claim 1, wherein: the mass percentage of the main catalytic active component, the cocatalyst and the coating auxiliary material is 1-5%/4-10%/85-95%, and the sum of the mass percentages of the main catalytic active component, the cocatalyst and the coating auxiliary material is 100%.
5. A catalyst for diesel engines based on highly dispersed perovskite catalytic components according to any one of claims 1 to 4, characterized in that: the mass percentage of the catalytic coating and the carrier is 15-30%/85-70%, and the sum of the mass percentages of the catalytic coating and the carrier is 100%.
6. A process for the preparation of a catalyst for diesel engines based on highly dispersed perovskite catalytic components as claimed in any one of claims 1 to 5, characterized in that: the specific process comprises the following steps:
step 1, designing a catalyst composition:
according to the proportions of the components in any one of claims 1 to 5, the following proportions are respectively designed: la in main catalytic active ingredient x Ce 1-x Mn y Bi 1-y O 3 Perovskite and MoO 3 In mass percent of La x Ce 1-x Mn y Bi 1-y O 3 Mole percent of La element and Ce element in perovskite, mole percent of Mn element and Bi element, and CeO in cocatalyst 2 And ZrO(s) 2 In mass percent of gamma-Al 2 O 3 Pure gamma-Al in coating auxiliary material 2 O 3 Powder and gamma-Al converted from aluminium sol 2 O 3 The mass percentage of the main catalytic active component, the cocatalyst and the coating auxiliary material, and the mass of the catalytic coating which can be generated by planning to configure the coating slurry;
step 2, la x Ce 1-x Mn y Bi 1-y O 3 Preparing a perovskite nanoparticle template:
calculating La in the main catalytic active component according to the proportion of each component designed in the step 1 and the quality of the catalytic coating which can be generated by planning to configure coating slurry x Ce 1-x Mn y Bi 1-y O 3 Quality of perovskite nanoparticle template and La x Ce 1-x Mn y Bi 1- y O 3 The mole number of La, ce, mn and Bi elements in the perovskite nano particle template;
bind to each 433.0g La (NO) 3 ) 3 ·6H 2 O preparation of 1mol La, per 434.1g Ce (NO) 3 ) 3 ·6H 2 O preparation of 1mol Ce per 173.0g Mn (CH) 3 COO) 2 Preparation of 1mol Mn per 485.1g Bi (NO 3 ) 3 ·5H 2 O preparation of 1mol Bi and La x Ce 1- x Mn y Bi 1-y O 3 The La is prepared by calculating the conversion ratio of the sum of the mole numbers of La, ce, mn and Bi elements in the perovskite nanoparticle template to the mole number of glucose used to be 1:1-2 and the weight of 180.2g per mole of glucose x Ce 1- x Mn y Bi 1-y O 3 La (NO) for perovskite nanoparticles 3 ) 3 ·6H 2 O、Ce(NO 3 ) 3 ·6H 2 O、Mn(CH 3 COO) 2 、Bi(NO 3 ) 3 ·5H 2 Mass of O and glucose;
weighing La (NO) of determined mass 3 ) 3 ·6H 2 O、Ce(NO 3 ) 3 ·6H 2 O、Mn(CH 3 COO) 2 、Bi(NO 3 ) 3 ·5H 2 O, glucose and a mass of La (NO) 3 ) 3 ·6H 2 O、Ce(NO 3 ) 3 ·6H 2 O、Mn(CH 3 COO) 2 Bi (NO) 3 ) 3 ·5H 2 In the range of 0.8 to 1.5 times the sum of O masses and D 50 Carbon black having a particle diameter of not more than 500nm, and adding 1g of carbon to the above 6 raw materials togetherIn the deionized water weighed according to the proportion of 30-50 mL of deionized water, carrying out ultrasonic oscillation for 6-8 h, and then heating the mixture of the 6 raw materials and the deionized water while carrying out ultrasonic oscillation, so that the mixture is evaporated to dryness after 6-8 h to form wet gel; drying the wet gel at 80-110 ℃ for 6-12 hours to obtain xerogel; heating the xerogel to 400 ℃ in a muffle furnace at a speed of 3 ℃/min and keeping for 2 hours, heating to 700-800 ℃ at a speed of 10 ℃/min, and calcining for 3-4 hours to obtain La x Ce 1-x Mn y Bi 1-y O 3 A perovskite nanoparticle template;
step 3, preparing main catalytic active components:
calculating MoO in the main catalytic active component according to the proportion of each component designed in the step 1 and the quality of the catalytic coating which can be generated by planning to configure coating slurry 3 Is the mass of (3); combined with each 196.0g (NH) 4 ) 2 MoO 4 Preparation of 144.0g MoO 3 The conversion ratio of (C) to (C) is calculated to obtain the (NH) required for the preparation of the main catalyst active ingredient 4 ) 2 MoO 4 Is the mass of (3);
weighing the (NH) 4 ) 2 MoO 4 La obtained by the preparation of step 2 x Ce 1-x Mn y Bi 1-y O 3 A perovskite nanoparticle template, and the (NH 4 ) 2 MoO 4 And La (La) x Ce 1-x Mn y Bi 1-y O 3 Perovskite nanoparticle template addition was performed according to 1g (NH 4 ) 2 MoO 4 In the deionized water which is weighed according to the proportion of 50-500 ml of deionized water, carrying out ultrasonic oscillation to form slurry; by NaOH or HNO 3 Adjusting the pH of the slurry to a pH in the range of 4 to 6 and grinding the slurry on a grinder to a pH D 50 The particle size is in the range of 800-1000 nm, and the ground slurry is heated while ultrasonic oscillation is carried out, so that the slurry is evaporated to dryness after 4-8 hours and becomes solid;
drying the dried solid at 80-110 ℃ for 6-12 h, presintering at 350 ℃ for 2h, and calcining at 500-550 ℃ for 2 ultra-high3h, la of powdery and massive solids obtained after calcination x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The composite catalytic material nano particles are the main catalytic active components of the catalyst;
step 4, preparing coating slurry:
calculating CeO required for preparing the catalytic coating according to the proportions of the components designed in the step 1 and the quality of the catalytic coating which can be generated by planning to configure the coating slurry 2 And ZrO(s) 2 Quality of (C) and gamma-Al 2 O 3 The quality of the coating auxiliary materials;
bind per 434.2g Ce (NO) 3 ) 3 ·6H 2 O preparation 172.1g CeO 2 Each 429.3g of Zr (NO) 3 ) 4 ·5H 2 O preparation 123.2gZrO 2 Al in aluminum sol 2 O 3 Calculated out the mass percent of Ce (NO) required for preparing the coating slurry 3 ) 3 ·6H 2 O、Zr(NO 3 ) 4 ·5H 2 O and the mass of the aluminum sol; in addition, the mass of polyethylene glycol consumed for preparing the catalytic coating is calculated according to the proportion of 5-15 g of polyethylene glycol with average molecular weight of 20000 required for each 100g of the catalytic coating;
weighing Ce (NO) with determined mass 3 ) 3 ·6H 2 O、Zr(NO 3 ) 4 ·5H 2 O, pure gamma-Al 2 O 3 Powder, aluminum sol, polyethylene glycol with molecular weight of 20000 and La prepared in step 3 x Ce 1-x Mn y Bi 1-y O 3 perovskite-MoO 3 The 6 raw materials are added into deionized water with the mass 5-15 times of the mass of the catalytic coating to be prepared together to form slurry by ultrasonic oscillation; by NaOH or HNO 3 Adjusting the pH of the slurry to a pH in the range of 5 to 7 and grinding the slurry on a grinder to a pH D 50 The grain diameter is in the range of 800-1000 nm, and the ground slurry is stirred for 48-72 h at the temperature of 50-70 ℃ to obtain coating slurry;
step 5, coating a catalytic coating on the carrier:
designing the quality of the support to which the catalytic coating is to be applied; weighing the carrier with determined mass, immersing the carrier in the coating slurry at 50-70 ℃ and ensuring that the upper end surface of the carrier is slightly higher than the slurry level; after the slurry naturally lifts all pore canals filled with the carrier, the carrier is taken out from the slurry, residual fluid in the pore canals is blown off, the slurry is dried for 4 to 16 hours at the temperature of 80 to 110 ℃, and then the slurry is baked for 2 to 4 hours at the temperature of 500 to 600 ℃; repeating the processes of dipping, drying and roasting for 2-3 times to obtain the catalyst for the diesel engine based on the high-dispersion perovskite catalytic component.
7. Use of a diesel engine catalyst based on highly dispersed perovskite catalytic components as defined in any one of claims 1 to 5, prepared according to the preparation method of claim 6, packaged as a Diesel Oxidation Catalyst (DOC), said diesel oxidation catalyst being mounted in a diesel exhaust passage for efficient oxidation purification of PM, HC and CO in diesel exhaust.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1473654A (en) * | 2002-08-06 | 2004-02-11 | 中国科学院大连化学物理研究所 | Composite oxide catalyst and its preparing method and use |
| JP2008004286A (en) * | 2006-06-20 | 2008-01-10 | Toyota Motor Corp | Perovskite type oxide particulate, perovskite type oxide carrying particle, catalyst material, catalyst material for oxygen reduction, catalyst material for fuel cell, and electrode for fuel cell |
| DE202012005818U1 (en) * | 2011-06-17 | 2012-07-13 | BLüCHER GMBH | Porous materials based on metallic mixed oxides |
| CN104707617A (en) * | 2015-03-02 | 2015-06-17 | 滁州学院 | Double-perovskite metal oxide catalyst and preparation method thereof |
| CN107970907A (en) * | 2016-10-21 | 2018-05-01 | 中国石油化工股份有限公司 | A kind of nano composite oxide catalyst and its preparation method and application |
| CN107983330A (en) * | 2017-11-24 | 2018-05-04 | 中国科学院长春应用化学研究所 | A kind of perovskite type catalyst of modification and preparation method thereof, the application in isoprene is catalyzed and synthesized |
| CN108883389A (en) * | 2016-02-22 | 2018-11-23 | 香港大学 | Produce the method with the porous crystalline material of structure of high uniformity |
| CN112221495A (en) * | 2020-10-13 | 2021-01-15 | 天津大学 | Catalyst for noble metal substituted perovskite diesel oxidation catalyst and preparation method thereof |
| EP3916819A1 (en) * | 2020-05-29 | 2021-12-01 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk Onderzoek TNO | Perovskite layer |
| CN113797915A (en) * | 2021-10-24 | 2021-12-17 | 合肥神舟催化净化器股份有限公司 | Diesel oxidation catalyst based on metal oxide nanoparticles, and preparation method and application thereof |
-
2022
- 2022-11-14 CN CN202211417963.2A patent/CN115805069B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1473654A (en) * | 2002-08-06 | 2004-02-11 | 中国科学院大连化学物理研究所 | Composite oxide catalyst and its preparing method and use |
| JP2008004286A (en) * | 2006-06-20 | 2008-01-10 | Toyota Motor Corp | Perovskite type oxide particulate, perovskite type oxide carrying particle, catalyst material, catalyst material for oxygen reduction, catalyst material for fuel cell, and electrode for fuel cell |
| DE202012005818U1 (en) * | 2011-06-17 | 2012-07-13 | BLüCHER GMBH | Porous materials based on metallic mixed oxides |
| CN104707617A (en) * | 2015-03-02 | 2015-06-17 | 滁州学院 | Double-perovskite metal oxide catalyst and preparation method thereof |
| CN108883389A (en) * | 2016-02-22 | 2018-11-23 | 香港大学 | Produce the method with the porous crystalline material of structure of high uniformity |
| CN107970907A (en) * | 2016-10-21 | 2018-05-01 | 中国石油化工股份有限公司 | A kind of nano composite oxide catalyst and its preparation method and application |
| CN107983330A (en) * | 2017-11-24 | 2018-05-04 | 中国科学院长春应用化学研究所 | A kind of perovskite type catalyst of modification and preparation method thereof, the application in isoprene is catalyzed and synthesized |
| EP3916819A1 (en) * | 2020-05-29 | 2021-12-01 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk Onderzoek TNO | Perovskite layer |
| CN112221495A (en) * | 2020-10-13 | 2021-01-15 | 天津大学 | Catalyst for noble metal substituted perovskite diesel oxidation catalyst and preparation method thereof |
| CN113797915A (en) * | 2021-10-24 | 2021-12-17 | 合肥神舟催化净化器股份有限公司 | Diesel oxidation catalyst based on metal oxide nanoparticles, and preparation method and application thereof |
Non-Patent Citations (6)
| Title |
|---|
| A comparative study of the physical properties of in-cylinder soot generated from the combustion of n-heptane and toluene/n-heptane in a diesel engine;Jiangjun Wei et al.;《Proceedings of the Combustion Institute》;第35卷;1939–1946 * |
| Fully vacuum–processed perovskite solar cells with high open circuit voltage using MoO3/NPB as hole extraction layers;Beom-Soo Kim et al.;《Organic Electronics》;第17卷;102–106 * |
| Structural Features of (Ce, La or Sr)(Mn or Co)O3 Nano- Perovskites as a Catalyst for Carbon Monoxide Oxidation;Mahnaz Ghiasi 、 Azim Malekzadeh;《Acta Metallurgica Sinica》;全文 * |
| Sulfur resistant LaxCe1−xNi0.5Cu0.5O3 catalysts for an ultra-high temperature water gas shift reaction;Usman Oemar et al.;《Catalysis Science & Technology》;第6卷;6569–6580 * |
| 低温氧化型过渡金属氧化物催化剂研究进展;刘东升;邹志强;姚成;孟明;;化学工业与工程(06);全文 * |
| 柴油车排放碳黑颗粒消除催化剂的研究进展;刘坚, 赵震, 徐春明;催化学报(08);全文 * |
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