阅读说明：本技术 一种三元氧化物非贵金属催化剂的制备方法 (Preparation method of ternary oxide non-noble metal catalyst ) 是由 程起林 吴亮 方辉旺 康选峰 吴承虎 姚晨晓 叶盛远 夏碧云 曹馨雅 于 2019-09-07 设计创作，主要内容包括：本发明涉及废气处理材料技术领域,具体为一种三元氧化物非贵金属催化剂的制备方法,通过选择Cu(NO3)3、Co(NO3)2、Ce(NO3)3为前驱体,选择糊精为添加剂,在100mL去离子水中溶解形成特定浓度的喷雾溶液。在超声雾化器中形成雾滴,载气将雾滴带入高温石英管式炉,前驱体热解后产品由滤纸进行收集,克服现有技术中存在铂系贵金属成本高、耐高温性差,低温催化效率降低等问题,能够作为催化燃烧应用中贵金属催化剂的低成本和高稳定性的替代品。(The invention relates to the technical field of waste gas treatment materials, in particular to a preparation method of a ternary oxide non-noble metal catalyst, which is characterized in that Cu (NO3)3, Co (NO3)2 and Ce (NO3)3 are selected as precursors, dextrin is selected as an additive, and the precursors are dissolved in 100mL of deionized water to form a spray solution with a specific concentration. The method has the advantages that fog drops are formed in the ultrasonic atomizer, the fog drops are carried into the high-temperature quartz tube furnace by carrier gas, products after precursor pyrolysis are collected by filter paper, the problems that platinum group precious metals are high in cost, poor in high temperature resistance, low in low-temperature catalytic efficiency and the like in the prior art are solved, and the method can be used as a substitute of a precious metal catalyst in catalytic combustion application, and is low in cost and high in stability.)

1. The preparation method of the ternary oxide non-noble metal catalyst is characterized by comprising the step of preparing CuO-Co with a hollow structure through an ultrasonic spray pyrolysis process₃O₄-CeO₂The ternary oxide catalyst microsphere comprises the following steps:

1) mixing three metal salts of Cu, Co and Ce to form a precursor, mixing the precursor with an additive, and dissolving the precursor with a solvent to prepare a precursor solution;

2) spraying the precursor solution by the ultrasonic spraying action of a spray pyrolysis device to obtain fog drops, and feeding the fog drops into a quartz tube furnace;

3) the precursor solution is dried in a quartz tube furnace and then undergoes a thermal decomposition reaction, thereby obtaining a product CuO-Co₃O₄-CeO₂Three-way catalyst microspheres, at which point the product was collected through filter paper.

Product CuO-Co₃O₄-CeO₂The particle size of the three-way catalyst microsphere is 0.4-3 microns, and the three-way catalyst microsphere has a typical hollow structure.

2. The method of claim 1, wherein the method comprises the steps of: the final product is xCuO-yCo₃O₄-zCeO₂Is shown in whichX is the mole fraction of Cu in the total metal ions, y is the mole fraction of Co in the total metal ions, and z is the mole fraction of Ce in the total metal ions; the regulation interval of x is 0.1-0.5, the regulation interval of y is 0.1-0.5, and the regulation interval of z is 0.2-0.8.

3. The method of claim 1, wherein the method comprises the steps of: the metal salt raw material of the precursor is Cu (NO)₃)₃、Co(NO₃)₂And Ce (NO)₃)₃。

4. The method of claim 1, wherein the method comprises the steps of: the additive is dextrin.

5. The method of claim 3, wherein the method comprises the steps of: in the precursor solution, the total concentration of metal ions is 0.1-0.5mol/L, and the addition amount of dextrin is 0.05-0.2 mol/L.

6. The method of claim 1, wherein the method comprises the steps of: the pyrolysis temperature in the quartz tube furnace is 400-1000 ℃.

7. The method of claim 1, wherein the method comprises the steps of: compared with binary CuO-Co, the prepared ternary non-noble metal catalyst₃O₄The catalytic performance is greatly improved, and the catalyst is free of C₃H₈Complete conversion of carbon monoxide is achieved at 130 ℃ and C₃H₈Complete conversion of carbon monoxide was achieved at 150 ℃ in the presence of this.

Technical Field

The invention relates to the technical field of waste gas treatment materials, in particular to a preparation method of a ternary oxide non-noble metal catalyst.

Background

In order to reduce greenhouse gas emissions and oil consumption, new fuel economy standards for passenger vehicles and light trucks have been proposed by countries throughout the world, and the combination of improving fuel economy while reducing exhaust gas pollutant emissions to meet these standards poses a significant challenge to the automotive industry.

Most commercial catalysts employed in automotive exhaust gas streams use supported noble metals of the platinum group, and the presence of hydrocarbons inhibits the active sites of the noble metals of the platinum group, limiting their use in low temperature catalysis. Meanwhile, the platinum group noble metal catalyst is easy to sinter at high temperature, which also causes the reduction of the conversion rate of key pollutants at low temperature. These key disadvantages and the high cost of precious metal materials have driven the need to develop low cost, high stability catalysts that can meet the requirements of complex exhaust gas streams.

Disclosure of Invention

The invention aims to provide a preparation method of a ternary oxide non-noble metal catalyst with low cost and high stability, which can meet the requirement of complex waste gas flow.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a preparation method of a ternary oxide non-noble metal catalyst, which comprises the step of preparing CuO-Co with a hollow structure through an ultrasonic spray pyrolysis process₃O₄-CeO₂The ternary oxide catalyst microsphere comprises the following steps:

1) mixing three metal salts of Cu, Co and Ce to form a precursor, mixing the precursor with an additive, and dissolving the precursor with a solvent to prepare a precursor solution;

2) spraying the precursor solution by the ultrasonic spraying action of a spray pyrolysis device to obtain fog drops, and feeding the fog drops into a quartz tube furnace;

3) the precursor solution is dried in a quartz tube furnace and then undergoes a thermal decomposition reaction, thereby obtaining a product CuO-Co₃O₄-CeO₂Three-way catalyst microspheres, at which point the product was collected through filter paper.

Product CuO-Co₃O₄-CeO₂The particle size of the three-way catalyst microsphere is 0.4-3 microns, and the three-way catalyst microsphere has a typical hollow structure.

Preferably, the final product is represented by xCuO-yCo₃O₄-zCeO₂Wherein x is the mole fraction of Cu to the total metal ions, y is the mole fraction of Co to the total metal ions, and z is the mole fraction of Ce to the total metal ions; the regulation interval of x is 0.1-0.5, the regulation interval of y is 0.1-0.5, and the regulation interval of z is 0.2-0.8.

Preferably, the metal salt raw material of the precursor is Cu (NO)₃)₃、Co(NO₃)₂And Ce (NO)₃)₃。

Preferably, the additive is dextrin.

Preferably, the total concentration of the metal ions in the precursor solution is 0.1-0.5mol/L, and the addition amount of the dextrin is 0.05-0.2 mol/L.

Preferably, the pyrolysis temperature in the quartz tube furnace is 400-1000 ℃.

Preferably, the prepared ternary non-noble metal catalyst is compared with binary CuO-Co₃O₄The catalytic performance is greatly improved, and the catalyst is free of C₃H₈Complete conversion of carbon monoxide is achieved at 130 ℃ and C₃H₈Complete conversion of carbon monoxide was achieved at 150 ℃ in the presence of this.

Compared with the prior art, the invention has the beneficial effects that: according to the preparation method of the ternary oxide non-noble metal catalyst, Cu (NO3)3, Co (NO3)2 and Ce (NO3)3 are selected as precursors, dextrin is selected as an additive, and the precursors and the additives are dissolved in 100mL of deionized water to form a spray solution with a specific concentration. The method has the advantages that fog drops are formed in the ultrasonic atomizer, the fog drops are carried into the high-temperature quartz tube furnace by carrier gas, products after precursor pyrolysis are collected by filter paper, the problems that platinum group precious metals are high in cost, poor in high temperature resistance, low in low-temperature catalytic efficiency and the like in the prior art are solved, and the method can be used as a substitute of a precious metal catalyst in catalytic combustion application, and is low in cost and high in stability.

Drawings

FIG. 1 is an X-ray diffraction pattern of various products prepared in examples 1-4 and comparative example 1;

FIG. 2(a) is a photograph of the product prepared in example 1 at a resolution of 2 μm under a scanning electron microscope;

FIG. 2(b) is a photograph of the product prepared in example 1 under a scanning electron microscope at a resolution of 500 nm;

FIG. 3(a) is a photograph of the product prepared in example 1 under a transmission electron microscope at a resolution of 500 nm;

FIG. 3(b) is a photograph of the product prepared in example 1 at a resolution of 5 nm under a transmission electron microscope;

FIG. 4(a) is a drawing at C₃H₈Graphs of catalytic performance of the products prepared in examples 1-4 and comparative example 1 in the absence;

FIG. 4(b) is a drawing at C₃H₈Graphs of the catalytic performance of the products prepared in examples 1-4 and comparative example 1 in the presence of the catalyst;

in the figure, xCuO-yCo₃O₄-zCeO₂Abbreviated CCC-xyz.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.