WO2021026964A1 - 一种稳定的铈锆固溶体及其制备方法、应用 - Google Patents

一种稳定的铈锆固溶体及其制备方法、应用 Download PDF

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WO2021026964A1
WO2021026964A1 PCT/CN2019/102760 CN2019102760W WO2021026964A1 WO 2021026964 A1 WO2021026964 A1 WO 2021026964A1 CN 2019102760 W CN2019102760 W CN 2019102760W WO 2021026964 A1 WO2021026964 A1 WO 2021026964A1
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cerium
solid solution
zirconium solid
zirconium
oxide
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PCT/CN2019/102760
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English (en)
French (fr)
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宋锡滨
张兵
张曦
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山东国瓷功能材料股份有限公司
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Priority to US17/040,884 priority Critical patent/US11865520B2/en
Priority to EP19916539.0A priority patent/EP3804847A4/en
Publication of WO2021026964A1 publication Critical patent/WO2021026964A1/zh

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • F01N2510/00—Surface coverings
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    • F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
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Definitions

  • the application relates to a cerium-zirconium solid solution and a preparation method and application thereof, and belongs to the field of adsorption catalyst materials.
  • Cerium-zirconium composite oxide is widely used in the field of mobile source catalysis due to its excellent oxygen storage and release performance and good aging performance.
  • the cerium-zirconium composite oxide also has the function of a carrier, which supports and disperses the active metal.
  • the change of the cerium-zirconium composite oxide formula has a significant impact on its physical and chemical properties and application properties.
  • the change of the molar ratio of cerium-zirconium composite oxide will affect its reduction temperature, oxygen storage performance and high-temperature aging performance, thereby affecting the cold-start catalytic performance of the mobile source catalytic application and the utilization efficiency of precious metals.
  • Air-fuel ratio A/F definition the quality of air consumed by the engine/the quality of fuel consumed by the engine.
  • the fuel can theoretically be completely combusted, and the exhaust after combustion can achieve the greatest degree of conversion of pollutants by relying on the remaining oxidizing substances under the action of the catalyst.
  • the fuel ratio control is automatically controlled by the sensor closed-loop system.
  • the intake of oxygen is sometimes insufficient and sometimes excessive relative to the gas injected into the cylinder.
  • the exhaust gas will contain excessive hydrocarbons and carbon monoxide and need to be catalytically burned, but the exhaust gas lacks oxygen, which makes it impossible to convert;
  • the air is excessive ( ⁇ 1), the exhaust gas contains Excessive oxygen generates a large amount of nitrogen oxides.
  • the reduction of nitrogen oxides to nitrogen mainly depends on hydrocarbons and carbon monoxide. Due to excessive oxygen, hydrocarbons and carbon monoxide will be catalyzed on the catalyst, making it difficult to reduce nitrogen oxides. Lead to excessive nitrogen oxides in the exhaust gas.
  • the cerium oxide in the cerium-zirconium solid solution has two valence states: trivalent and tetravalent, which can be freely converted under certain conditions.
  • trivalent cerium absorbs oxygen and stores it and converts it into tetravalent cerium, thereby ensuring the reduction of nitrogen oxides; when the exhaust gas lacks oxygen, tetravalent cerium will release oxygen to ensure sufficient hydrocarbons and carbon monoxide Oxidation.
  • cerium-zirconium solid solution and its preparation method and application are provided.
  • the cerium-zirconium solid solution phase in the cerium-zirconium solid solution contains a specific proportion of trivalent cerium ions and tetravalent cerium ions.
  • the cerium-zirconium solid solution has a high oxygen storage and release rate, a high oxygen storage and release, and the process of oxygen storage and release
  • the cerium-zirconium solid solution has a stable structure; the preparation method of the cerium-zirconium solid solution is simple and easy to control.
  • the prepared cerium-zirconium solid solution has a high specific surface area and a high specific surface area after 1100 °C aging, and has a large oxygen storage capacity.
  • the phase structure of the cerium-zirconium solid solution is stable; the cerium-zirconium solid solution as a catalyst has high efficiency in catalyzing oxidation/reduction gas, stable structure and long service life, and the cost of using the catalyst is low.
  • a cerium-zirconium solid solution there is provided a cerium-zirconium solid solution.
  • the cerium-zirconium solid solution phase in the cerium-zirconium solid solution contains a specific ratio of trivalent cerium ions and tetravalent cerium ions, which can not only ensure the oxygen storage and release rate, but also The amount of oxygen stored and released for the cerium-zirconium solid solution can be realized, and the stability of the cerium-zirconium solid solution structure can be ensured.
  • the cerium-zirconium solid solution includes a cerium-zirconium solid solution phase, the cerium-zirconium solid solution phase includes trivalent cerium ions and tetravalent cerium ions, and the Ce 3+ /Ce 4+ molar ratio is 0.05-0.8:1.
  • the Ce 3+ /Ce 4+ molar ratio is 0.1-0.5:1.
  • the lower limit of the range of Ce 3+ /Ce 4+ molar ratio is selected from 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1 or 0.45:1, and the upper limit is selected from 0.15: 1. 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1 or 0.45:1.
  • the Ce 3+ /Ce 4+ molar ratio is 0.15-0.5:1.
  • the Ce 3+ /Ce 4+ molar ratio is 0.16-0.5:1.
  • the cerium-zirconium solid solution includes cerium oxide, ZrO 2 , and the first rare earth element oxide in a weight ratio of 20-50:20-80:2-20;
  • the first rare earth element is selected from at least one of rare earth elements other than cerium, transition metal elements, and alkaline earth metal elements.
  • the first rare earth element is selected from at least one of lanthanum, yttrium, praseodymium, neodymium and samarium.
  • the cerium-zirconium solid solution phase includes CeO 2 , ZrO 2 , La 2 O 3 and Y 2 O 3 in a weight ratio of 30-50:40-60:3-7:3-7.
  • the weight composition of the cerium-zirconium solid solution phase includes 40% CeO 2 , 50% ZrO 2 , 5% La 2 O 3 , and 5% Y 2 O 3 .
  • the cerium-zirconium solid solution further includes a second rare earth element oxide, and the weight ratio of the cerium oxide to the second rare earth element oxide is 20-50:2-5;
  • the second rare earth element is selected from at least one of promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and scandium.
  • the second rare earth element is selected from at least one of rare earth elements other than cerium, transition metal elements, and alkaline earth metal elements.
  • the cerium-zirconium solid solution includes cerium oxide, ZrO 2 , the first rare earth element oxide and the second rare earth element oxide in a weight ratio of 25-45:30-70:3-15:2-4 .
  • the cerium-zirconium solid solution phase includes CeO 2 , ZrO 2 , La 2 O 3 and Pr 6 O 11 in a weight ratio of 10-30:50-75:1-5:4.5-17.
  • the weight composition of the cerium-zirconium solid solution includes 20% CeO 2 , 73% ZrO 2 , 2% La 2 O 3 and 5% Pr 6 O 11 .
  • the oxygen storage capacity is not less than 540 ⁇ mol[O]/g.
  • the specific surface area of the cerium-zirconium solid solution treated at 1100°C for 4h is not less than 30m 2 /g.
  • the oxygen storage capacity is greater than 600 ⁇ mol[O]/g; and/or
  • the specific surface area of the cerium-zirconium solid solution treated at 1100° C. for 4 hours is greater than 35 m 2 /g.
  • a method for preparing a cerium-zirconium solid solution is provided.
  • the preparation method of the cerium-zirconium solid solution is simple and easy to control.
  • the specific surface area of the prepared cerium-zirconium solid solution and the specific surface area after 1100°C aging are high.
  • the oxygen storage capacity is large, and the cerium-zirconium solid solution phase structure during the oxygen storage and release process is stable.
  • the preparation method of the cerium-zirconium solid solution includes the following steps:
  • Oxidation reaction Add hydrogen peroxide to the acidic initial mixture according to the required amount of trivalent cerium ions and tetravalent cerium ions, and add a precipitant to adjust the pH of the solution to 10-11 to prepare a precursor solution;
  • the first hydrothermal reaction after the precursor solution is subjected to the first hydrothermal reaction, it is calcined in an inert gas to obtain the cerium-zirconium solid solution.
  • the M element is selected from at least one of rare earth elements, transition metal elements, and alkaline earth metal elements other than cerium.
  • the precipitation agent is selected from at least one of ammonia, sodium hydroxide, amines and urea.
  • the precipitation agent is selected from ammonia or urea.
  • the precipitation agent is ammonia water.
  • the trivalent cerium ions, tetravalent zirconium ions and M ions in the raw materials for configuring the initial mixture are derived from nitrate, phosphate, sulfate, acetate, oxalate, chloride and carbonic acid At least one of salt.
  • the trivalent cerium ions and tetravalent zirconium ions in the raw materials for configuring the initial mixture are derived from cerium nitrate and zirconyl nitrate.
  • the step 1) mixing includes the step of preparing an initial mixture of an aqueous solution containing trivalent cerium ions, tetravalent zirconium ions and M ions.
  • the step 2) oxidation reaction includes the following steps:
  • an alkaline precipitation agent is added to the initial mixture until the pH of the solution is 1.5-2.0.
  • the temperature of the second hydrothermal reaction is 150-220°C, and the time is 15-20h.
  • the temperature of the first hydrothermal reaction is 180-220°C, and the time is 10-20h.
  • a precipitation agent is added to adjust the pH of the solution to 8.5-9.5.
  • the step 2 is aged for 3-4 hours.
  • the temperature of the first hydrothermal reaction is 180-220°C, and the time is 10-20h.
  • the firing conditions in the step 3) are firing in an inert gas at 750°C-850°C for 4 hours.
  • the inert gas is selected from at least one of nitrogen, argon and helium.
  • the cerium-zirconium solid solution includes 20wt%-50wt% cerium oxide and 20wt%-80wt% ZrO 2 , and the cerium oxide includes trivalent cerium ions and tetravalent cerium ions in a molar ratio of 0.05-0.8:1. Valence cerium ion.
  • the cerium-zirconium solid solution includes 30wt%-50wt% cerium oxide and 40wt%-50wt% ZrO 2 , and the cerium oxide includes trivalent cerium ions and tetravalent cerium ions in a molar ratio of 0.15-0.5:1. Valence cerium ion. Furthermore, the cerium oxide includes trivalent cerium ions and tetravalent cerium ions in a molar ratio of 0.16-0.5:1.
  • a catalyst is provided.
  • a solid solution of cerium and zirconium has high efficiency, stable structure and long service life for catalyzing oxidation/reduction gas, and the cost of using the catalyst is low.
  • the catalyst comprises a solid solution of cerium and zirconium, and the solid solution of cerium and zirconium is selected from:
  • cerium-zirconium solid solution described above is calcined at 500-1200°C for at least 1 hour or the cerium-zirconium solid solution prepared by any of the above methods is calcined at 500-1200°C for at least 1 hour.
  • an application of a catalyst which includes a cerium-zirconium solid solution or an application of the catalyst, characterized in that the application is selected from any one of I or II:
  • the mobile source exhaust includes motor vehicle exhaust purification.
  • the metals Zr and M in the cerium-zirconium solid solution except cerium are the highest and most stable normal valence states.
  • the valence state of the raw materials of Zr and M is not limited, if it is a reductive low-valence state When adding hydrogen peroxide, it is necessary to add the corresponding oxidation amount.
  • the raw materials of Zr and M are both in the highest and most stable normal valence state.
  • the cerium-zirconium solid solution phase in the cerium-zirconium solid solution contains a specific ratio of trivalent cerium ions and tetravalent cerium ions, and the cerium-zirconium solid solution has a high oxygen storage and release rate and a storage and release amount of oxygen High, and the solid solution structure of cerium and zirconium in the process of storing and releasing oxygen is stable and has good catalytic performance.
  • the method is simple and easy to control.
  • the prepared cerium-zirconium solid solution has a high specific surface area and a high specific surface area after 1100°C aging, large oxygen storage, and oxygen storage and oxygen release processes.
  • the cerium-zirconium solid solution phase structure is stable.
  • the cerium-zirconium solid solution has high efficiency as a catalyst for catalyzing oxidation/reduction gas, the catalyst has good catalytic performance at different fuel ratios, the structure is stable and the service life is long, and the cost of using the catalyst is low.
  • the catalyst is used to catalyze the oxidation/reduction of gases.
  • the catalyst can catalyze oxidizing or reducing gases. There are many types of gases used; and its stable catalytic performance at high temperatures is practical There are many scenes.
  • Figure 1 shows the XPS spectrum of cerium-zirconium solid solution 1#-1;
  • Figure 2 shows the XPS spectrum of cerium-zirconium solid solution 1#-4;
  • Figure 3 shows the XPS spectrum of cerium-zirconium solid solution 1#-8;
  • Figure 4 shows the XPS spectrum of cerium-zirconium solid solution 2#-1;
  • Figure 5 shows the XPS spectrum of cerium-zirconium solid solution 2#-4.
  • the instrument for detecting Ce 3+ /Ce 4+ is a kratos-ultra DLD X-ray photoelectron spectrometer from Shimadzu Corporation.
  • the catalyst evaluation instrument is Hinachenke, HN-CK-21 infrared flue gas analyzer
  • Catalytic evaluation adopts the method of simulating exhaust gas.
  • Carrier gas is Ar;
  • catalyst loading is 0.3g, 40-60 mesh, mass space velocity is 40000h -1 , and the test temperature is 400°C;
  • the preparation method of the cerium-zirconium solid solution includes the following steps:
  • the first hydrothermal reaction the aged materials are introduced into the autoclave, and hydrothermally heated between 180-220°C for 10-20h; the product after the reaction is washed and dried, and then passed through 750°C in an inert atmosphere Heat treatment at -850°C for 4h to obtain the final product.
  • the preparation method of cerium-zirconium solid solution 1#-1 includes the following steps (the molar amount of hydrogen peroxide is 1.3 times the molar amount of Ce 3+ ion):
  • the molar ratio of Ce 3+ to hydrogen peroxide was changed to prepare the cerium-zirconium solid solution 1#-2 ⁇ 1#-8 and the cerium-zirconium solid solution 1#-
  • the specific molar ratio of 1 to 1#-8 and the molar ratio of Ce 3+ /Ce 4+ of the prepared cerium-zirconium solid solution 1#-1 to 1#-8 are shown in Table 1.
  • the raw material Ce 3+ was replaced with Ce 4+ and the hydrogen peroxide was not added in the step to prepare the cerium-zirconium solid solution 1#-9.
  • the molar ratio of Ce 3+ /Ce 4+ was tested using XPS, where the XPS spectra of 1#-1, 1#-4, and 1#-8 of cerium-zirconium solid solutions were taken as examples to illustrate Test spectrum result of Ce 3+ /Ce 4+ . It can be seen from Figure 1-3 that the cerium-zirconium solid solutions 1#-1, 1#-4, and 1#-8 simultaneously contain Ce 3+ /Ce 4+ and its content.
  • the cerium-zirconium solid solution 2#-1 including cerium, zirconium, lanthanum and praseodymium, and the cerium-zirconium solid solution 2#-1 according to the weight of the oxides of cerium oxide, zirconium oxide, lanthanum oxide, and praseodymium, are recorded as follows: 20wt% cerium oxide, 73wt % Zirconia, 2wt% lanthanum oxide, 5wt% praseodymium oxide.
  • the preparation method of cerium-zirconium solid solution 2#-1 includes the following steps (the molar amount of hydrogen peroxide is 1.3 times the molar amount of Ce 3+ ion):
  • the molar ratio of Ce 3+ to hydrogen peroxide was changed to prepare the cerium-zirconium solid solution 2#-2 ⁇ 2#-8 and the cerium-zirconium solid solution 2#-
  • the specific molar ratio of 1-2#-8 and the molar ratio of Ce 3+ /Ce 4+ of the prepared cerium-zirconium solid solution 2#-1 ⁇ 2#-8 are shown in Table 2.
  • the raw material Ce 3+ was replaced with Ce 4+ and the hydrogen peroxide was not added in the step to prepare the cerium-zirconium solid solution 2#-9.
  • the molar ratio of Ce 3+ /Ce 4+ was tested using XPS.
  • the XPS spectra of 2#-1 and 2#-4 of cerium-zirconium solid solution were taken as examples to illustrate the difference of Ce 3+ /Ce 4+ Test spectrum result. It can be seen from Figure 4 and Figure 5 that the cerium-zirconium solid solutions 2#-1 and 2#-4 also contain Ce 3+ /Ce 4+ and its content.
  • the cerium-zirconium solid solution 1#-6 and the cerium-zirconium solid solution 2#-6 with the ratio of Ce 3+ /Ce 4+ between 0.1-0.5 are treated at 750°C and the oxygen storage capacity is not less than 561 ⁇ mol after 4 hours. [O]/g;
  • the specific surface area of the cerium-zirconium solid solution 1#-6 and 2#-6 treated at 1100°C for 4h is not less than 35m 2 /g.
  • Cerium-zirconium solid solution 1#-2 has been treated at 750°C for 4h and the oxygen storage capacity is as high as 656 ⁇ mol[O]/g; Cerium-zirconium solid solution 1#-1 treated at 1100°C for 4h has a specific surface area of up to 40m 2 /g.
  • the oxygen storage capacity of cerium-zirconium solid solution 1#-2 treated at 1100°C for 4h can reach 623 ⁇ mol[O]/g.
  • Cerium-zirconium solid solution 1#-6 and cerium-zirconium solid solution 2#-6 with the ratio of Ce 3+ /Ce 4+ between 0.1 and 0.5 showed better oxygen storage performance, indicating that it has a more stable crystal structure .
  • the catalytically active component palladium was loaded on the cerium-zirconium solid solution 1#-1 ⁇ 1#-9, 2#-1 ⁇ 2#-9 by the equal volume impregnation method to prepare the catalyst 1#-1 ⁇ 1#-9, 2 #-1 ⁇ 2#-9, catalysts 1#-1 ⁇ 1#-9, 2#-1 ⁇ 2#-9 have the same palladium loading amount of 1.5wt%.
  • cerium-zirconium solid solution 1#-1 Take the cerium-zirconium solid solution 1#-1 as an example to illustrate the specific loading method, which includes: using chloropalladic acid solution (H 2 PdCl 4 ) as the precursor dipping solution, impregnating the cerium-zirconium solid solution 1#-1, and the loading amount is 1.5wt%; the loaded slurry was dried in a rotary evaporator, then placed in a blast drying oven at 110°C for 3 hours, and then placed in a calcining furnace at 500°C in an air atmosphere for 3 hours.
  • chloropalladic acid solution H 2 PdCl 4
  • the cerium-zirconium solid solution 1#-1 ⁇ 1#-8 were aged at 1100°C for 4h to obtain aged cerium-zirconium solid solution 1#-1 ⁇ 1#-8.
  • the loading method of Example 6 was used to combine the same amount of palladium
  • the aged catalysts 1#-1 to 1#-8 are prepared by supporting the aged cerium-zirconium solid solution 1#-1 ⁇ 1#-8.
  • the conversion rate of aged catalyst 1#-1 ⁇ 1#-8 to NO 2 under different ⁇ is shown in Table 7. From the data in Table 7, it can be seen that the ratio of Ce 3+ /Ce 4+ is 0.1 Between -0.7, the aged catalyst 1#-1 ⁇ 1#-8 has higher catalytic activity for NO 2 ; when the ratio of Ce 3+ /Ce 4+ is between 0.1-0.5, the aged catalyst 1#-1 ⁇ 1#-8 has higher catalytic activity for NO 2 , indicating that when the ratio of Ce 3+ /Ce 4+ is between 0.1-0.5, it shows better structural stability.

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Abstract

本申请公开了一种铈锆固溶体及其制备方法、应用，属于吸附催化剂材料领域。该铈锆固溶体包括铈锆固溶体相，所述铈锆固溶体相中的Ce 3+/Ce 4+摩尔比为0.05-0.8:1。本申请中的铈锆固溶体中的铈锆固溶体相中包含特定比例的三价铈离子和四价铈离子，该铈锆固溶体的储放氧速率高，储放氧量高，且储放氧的过程中的铈锆固溶体结构稳定，催化性能好；包含该铈锆固溶体的催化剂在不同燃油比下均具有良好的催化性能。

Description

一种稳定的铈锆固溶体及其制备方法、应用 技术领域
本申请涉及一种铈锆固溶体及其制备方法、应用，属于吸附催化剂材料领域。
背景技术
铈锆复合氧化物因其优异的储放氧性能及良好的老化性能被广泛应用于移动源催化领域。铈锆复合氧化物除了参与催化反应外，还具有载体的功能，对活性金属起到了支撑分散的作用。铈锆复合氧化物配方的改变对其物化性能及应用性能均有明显的影响。铈锆复合氧化物摩尔比例的改变会影响其还原温度、储氧性能及高温老化性能，从而影响移动源催化应用端的冷启动催化性能及贵金属的利用效率。
但在尾气催化反应中，三效催化剂既要实现氮氧化物的还原，又要实现对未完全燃烧剩余的一氧化碳、烃类的氧化。要想使这三类污染物达到最高的转化率，燃油反应体系中的氧含量相对于燃油必须处于理论反应计量点附近。只有在理论空燃比附近，三效催化剂才能实现对氮氧化物、一氧化碳、烃类三种污染物的最大程度的转化。空燃比A/F定义：发动机消耗的空气质量/发动机消耗的燃油质量。当A/F＝14.6(λ＝1)时，燃料理论上可以完全燃烧，燃烧后排出的尾气在催化剂的作用下依靠本身剩余的氧化性物质可以实现对污染物最大程度的转化。燃油比的控制是通过传感器闭环系统自动进行控制的。
但在实际行驶过程中，由于工况比较复杂，吸入的氧气相对于气缸内喷入的油气来说，有时会不足，有时会过量。当油气过量(λ＞1)时，尾气中会含有过量的烃类及一氧化碳需要催化燃烧掉，但尾气中因为缺乏氧气，导致其无法转化；当空气过量(λ＜1)时，尾气中含有过量的 氧气，从而生成大量的氮氧化物，氮氧化物还原为氮气主要依靠烃类及一氧化碳，由于氧气过量，烃类及一氧化碳会在催化剂上被大量催化掉，从而难以还原氮氧化物，从而导致尾气中氮氧化物超标。
铈锆固溶体中的氧化铈具有三价及四价两种价态，在一定条件下可以自由转换。尾气中空气过量时，三价铈吸收氧气储存起来，同时转化为四价铈，从而保证了氮氧化物的还原；尾气中缺乏氧气时，四价铈会释放氧气，保证烃类及一氧化碳的充分氧化。
但三价铈与四价铈的相互转换是一个动态平衡的问题，三价铈转化为四价铈，原子半径减小，导致固溶体晶格收缩；四价铈转化为三价铈，原子半径增大，导致铈锆固溶体晶格膨胀；晶格的收缩及膨胀都会导致铈锆固溶体结构的不稳定，从而导致团聚或者孔道的坍塌，影响催化剂的寿命及催化活性。
发明内容
为了解决上述问题，提供了一种铈锆固溶体及其制备方法、应用。该铈锆固溶体中的铈锆固溶体相中包含特定比例的三价铈离子和四价铈离子，该铈锆固溶体的储放氧速率高，储放氧量高，且储放氧的过程中的铈锆固溶体结构稳定；该铈锆固溶体的制备方法简单、容易控制，制得的铈锆固溶的比表面积及1100℃老化后的比表面积高，储氧量大，储氧、放氧过程的铈锆固溶体相结构稳定；铈锆固溶体作为催化剂催化氧化/还原气体的效率高、结构稳定使用寿命长，进而使用该催化剂的成本低。
根据本申请的一个方面，提供了一种铈锆固溶体，该铈锆固溶体中的铈锆固溶体相中包含特定比例的三价铈离子和四价铈离子，既能保证储放氧速率，又能实现对铈锆固溶体储放氧数量，又能保证铈锆固溶体结构的稳定性。
该铈锆固溶体包括铈锆固溶体相，所述铈锆固溶体相包含三价铈离子和四价铈离子，所述Ce 3+/Ce 4+摩尔比为0.05-0.8:1。
可选地，所述Ce 3+/Ce 4+摩尔比为0.1-0.5:1。进一步地，Ce 3+/Ce 4+摩尔比的范围下限选自0.15:1、0.2:1、0.25:1、0.3:1、0.35:1、0.4:1或0.45:1，上限选自0.15:1、0.2:1、0.25:1、0.3:1、0.35:1、0.4:1或0.45:1。进一步地，所述Ce 3+/Ce 4+摩尔比为0.15-0.5:1。更进一步地，所述Ce 3+/Ce 4+摩尔比为0.16-0.5:1。
可选地，所述铈锆固溶体包括重量比为20-50:20-80:2-20的铈的氧化物、ZrO 2、第一稀土元素氧化物；
所述第一稀土元素选自除铈外的稀土元素、过渡金属元素和碱土金属元素中的至少一种。
优选地，所述第一稀土元素选自镧、钇、镨、钕和钐中的至少一种。
进一步地，所述铈锆固溶体相包括重量比为30-50:40-60:3-7:3-7的CeO 2、ZrO 2、La 2O 3和Y 2O 3。作为一种实施方式，所述铈锆固溶体相的重量组成包括40％CeO 2、50％ZrO 2、5％La 2O 3、5％Y 2O 3。
可选地，所述铈锆固溶体还包括第二稀土元素氧化物，所述铈的氧化物与第二稀土元素氧化物的重量比为20-50：2-5；
所述第二稀土元素选自钷、钐、铕、钆、铽、镝、钬、铒、铥、镱、镥和钪中的至少一种。所述第二稀土元素选自除铈外的稀土元素、过渡金属元素和碱土金属元素中的至少一种。
可选地，所述铈锆固溶体包括重量比为25-45:30-70:3-15:2-4的铈的氧化物、ZrO 2、第一稀土元素氧化物和第二稀土元素氧化物。
进一步地，所述铈锆固溶体相包括重量比为10-30:50-75:1-5:4.5-17的CeO 2、ZrO 2、La 2O 3和Pr 6O 11。作为一种实施方式，所述铈锆固溶体的重量组成包括20％CeO 2、73％ZrO 2、2％La 2O 3和5％Pr 6O 11。
可选地，所述铈锆固溶体经过750℃热处理4h后，储氧量不低于540μmol[O]/g；和/或
所述铈锆固溶体在1100℃处理4h的比表面积不低于30m 2/g。
优选地，所述铈锆固溶体经过750℃热处理4h后，储氧量大于600μmol[O]/g；和/或
所述铈锆固溶体在1100℃处理4h的比表面积大于35m 2/g。
根据本申请的另一个方面，提供了一种铈锆固溶体的制备方法，该铈锆固溶体的制备方法简单、容易控制，制得的铈锆固溶体的比表面积及1100℃老化后的比表面积高，储氧量大，储氧、放氧过程的铈锆固溶体相结构稳定。
该铈锆固溶体的制备方法包括下述步骤：
1)混料：配制包含三价铈离子和锆离子的水溶液的初混物；
2)氧化反应：根据需要的三价铈离子和四价铈离子量向酸性的初混物中加入过氧化氢，加入沉淀剂调节溶液的pH为10-11，制得前驱体溶液；
3)第一水热反应：将前驱体溶液进行第一水热反应后，在非活性气体中焙烧，即制得所述的铈锆固溶体。所述M元素选自除铈外的稀土元素、过渡金属元素和碱土金属元素中的至少一种。
可选地，所述沉淀剂选自氨水、氢氧化钠、胺类和尿素中的至少一种。优选地，所述沉淀剂选自氨水或尿素。优选地，所述沉淀剂为氨水。
可选地，所述配置初混物的原料中的三价铈离子、四价锆离子和M离子来自于硝酸盐、磷酸盐、硫酸盐、醋酸盐、草酸盐、氯化物和碳酸盐中的至少一种。优选地，所述配置初混物的原料中的三价铈离子、四价锆离子来自于硝酸铈和硝酸氧锆。
优选地，所述步骤1)混料包括步骤：配置包含三价铈离子、四价锆 离子和M离子的水溶液的初混物。
优选地，所述步骤2)氧化反应包括下述步骤：
①向初混物中加入碱性沉淀剂至溶液pH为1.0-2.5；根据需要的三价铈离子和四价铈离子量向初混物中加入30％的过氧化氢水溶液，搅拌至少1h，进行第二水热反应；和
②加入沉淀剂调节溶液的pH为10-11，老化至少1h，制得前驱体溶液。
优选地，向初混物中加入碱性沉淀剂至溶液pH为1.5-2.0。
优选地，加入过氧化氢水溶液后搅拌2-3h。
可选地，所述第二水热反应的温度为150-220℃，时间为15-20h。
可选地，所述第一水热反应的温度为180-220℃，时间为10-20h。
优选地，所述步骤②加入沉淀剂调节溶液的pH值为8.5-9.5。
优选地，所述步骤②老化3-4h。
可选地，所述第一水热反应的温度为180-220℃，时间为10-20h。
优选地，所述步骤3)中的焙烧的条件为在非活性气体中750℃-850℃焙烧4h。优选地，所述非活性气体选自氮气、氩气和氦气中的至少一种。
可选地，所述铈锆固溶体包括20wt％-50wt％铈的氧化物和20wt％-80wt％ZrO 2，所述铈的氧化物包括摩尔比为0.05-0.8:1的三价铈离子和四价铈离子。
可选地，所述铈锆固溶体包括30wt％-50wt％铈的氧化物和40wt％-50wt％ZrO 2，所述铈的氧化物包括摩尔比为0.15-0.5:1的三价铈离子和四价铈离子。更进一步地，所述铈的氧化物包括摩尔比为0.16-0.5:1的三价铈离子和四价铈离子。
根据本申请的又一个方面，提供了一种催化剂，铈锆固溶体作为催化剂催化氧化/还原气体的效率高、结构稳定、使用寿命长，进而使用该 催化剂的成本低。
所述催化剂包含铈锆固溶体，所述铈锆固溶体选自：
上述任一所述的铈锆固溶体或，由上述任一所述的方法制得的铈锆固溶体，或
上述任一所述的铈锆固溶体经500-1200℃焙烧至少1h或，由上述任一所述的方法制得的铈锆固溶体经500-1200℃焙烧至少1h。
根据本申请的再一个方面，提供了一种催化剂的应用，其包括铈锆固溶体或所述的催化剂的应用，其特征在于，所述应用选自I或II中的任一种：
I、催化转化选自CH 4、C 3H 8、C 2H 6、NO 2、NO、CO、H 2O或CO 2中的一种或任意几种气体的应用；
II、在移动源尾气、废气处理、天然气催化燃烧、有机废气净化处理或工业废气脱硝处理中的应用。所述移动源尾气包括机动车尾气净化。
本申请中，铈锆固溶体中的除铈外的其它金属Zr、M皆为最高、最稳定的正价态，Zr、M的原料的价态不进行限定，若为有还原性的低价态在添加双氧水时需要添加对应的氧化的量，优选Zr、M的原料皆为最高、最稳定的正价态。
本申请的有益效果包括但不限于：
1.根据本申请的铈锆固溶体，该铈锆固溶体中的铈锆固溶体相中包含特定比例的三价铈离子和四价铈离子，该铈锆固溶体的储放氧速率高，储放氧量高，且储放氧的过程中的铈锆固溶体结构稳定，催化性能好。
2.根据本申请的铈锆固溶体的制备方法，具有方法简单、容易控制，制得的铈锆固溶体的比表面积及1100℃老化后的比表面积高，储氧量大，储氧、放氧过程的铈锆固溶体相结构稳定。
3.根据本申请的催化剂，铈锆固溶体作为催化剂催化氧化/还原气 体的效率高，催化剂在不同燃油比下均具有良好的催化性能，结构稳定使用寿命长，进而使用该催化剂的成本低。
4.根据本申请的催化剂的应用，催化剂用于催化氧化/还原气体，催化剂可以催化具有氧化性或还原性的气体，使用的气体的种类多；且其在高温稳定的催化性能，实际应用的场景多。
附图说明
此处所说明的附图用来提供对本申请的进一步理解，构成本申请的一部分，本申请的示意性实施例及其说明用于解释本申请，并不构成对本申请的不当限定。在附图中：
图1为铈锆固溶体1#-1的XPS图谱；
图2为铈锆固溶体1#-4的XPS图谱；
图3为铈锆固溶体1#-8的XPS图谱；
图4为铈锆固溶体2#-1的XPS图谱；
图5为铈锆固溶体2#-4的XPS图谱。
具体实施方式
下面结合实施例详述本申请，但本申请并不局限于这些实施例。
如无特别说明，本申请的实施例中的原料和催化剂均通过商业途径购买。
本申请的实施例中分析方法如下：
1、检测Ce 3+/Ce 4+的仪器为岛津公司kratos-ultra DLD型X射线光电子能谱仪。
2、利用美国麦克仪器公司的Micromeritics TriStar Ⅱ型全自动吸附仪进行铈锆固溶体比表面的分析。
3、利用康塔公司的ChemBET-3000仪器进行铈锆固溶体储氧量的分 析。
4、催化剂评价仪器为海纳辰科，HN-CK-21红外烟气分析仪；
催化评价采用模拟尾气的方法，将空燃比λ定义为：λ＝(2V NO2+2.5V O2)/(2V CO+V C2H6)，V代表最终流经催化剂床层的混合气的体积百分含量；载气为Ar；催化剂装填量0.3g，40-60目，质量空速40000h -1，测试取点温度400℃；
通过控制气体的百分含量，在理论空燃比1附近波动取点，检测在不同空燃比下，不同Ce 3+/Ce 4+比例对催化反应的影响，λ取值：0.9，0.95，1.0，1.05，1.10。
本申请的实施例中，1摩尔Ce 3+氧化至Ce 4+理论值需要1mol过氧化氢。
根据本申请的一种实施方式，铈锆固溶体的制备方法包括下述步骤：
1)混料：配置三价铈离子、四价锆离子及其它稀土配成澄清的水溶液为初混物；
2)氧化反应：
①将溶液在一定水浴温度下搅拌至澄清，边搅拌边滴加碱性沉淀剂至溶液pH为1.0-2.5，优选1.5-2.0；将调完PH后的溶液加入一定量的质量浓度为30％的过氧化氢，并继续搅拌2-3h；将溶液引入至高压反应釜中，在150-220℃之间水热15-20h；
②第二水热反应后的物料在一定温度下以一定的速度滴加碱性沉淀剂至PH为8.0-10.0，优选8.5-9.5；将调完PH后的物料继续在一定水浴温度下老化3-4h；
3)第一水热反应：将老化后的物料引入至高压反应釜中，在180-220℃之间水热10-20h；反应后的产物经过洗涤、干燥后，在惰性气氛下经过750℃-850℃热处理4h，得到最终产物。
实施例1铈锆镧钇的铈锆固溶体1#-1的制备
包括铈、锆、镧和钇的铈锆固溶体1-1#，铈锆固溶体1#按氧化铈、氧化锆、氧化镧、氧化钇的氧化物重量记比例为：40wt％氧化铈，50wt％氧化锆，5wt％氧化镧，5wt％氧化钇,总氧化物浓度100g/l。
铈锆固溶体1#-1的制备方法包括下述步骤(过氧化氢摩尔量为Ce 3+离子摩尔量的1.3倍)：
1)在第一个烧杯中，将280g氧化铈对应的硝酸亚铈溶于500mL去离子水中,搅拌1h；第二个烧杯中，加入350g氧化锆对应的硝酸锆，并用1000mL去离子水溶解，搅拌1h；在第三个烧杯中，将35g氧化镧对应的硝酸镧及35g氧化钇对应的硝酸钇用1000mL去离子水溶解，溶液搅拌至澄清。
2)将三个烧杯中的溶液混合，搅拌至澄清，在40℃水浴条件下用氨水调节PH至2.0，此时溶液为清液，加入239.8g浓度30％的过氧化氢，搅拌2h，无沉淀生成。将溶液定容至7L，并引入至10L搪瓷水热合成釜中，反应釜上方用氮气密封，180℃水热20h。将水热后的产物用氨水调节PH在9-10之间，将调完PH后的物料继续在40℃水浴温度下老化3h。
3)将老化后的物料引入至高压反应釜中180℃水热10h；反应后的产物加入300g月桂酸，搅拌30分钟，然后抽滤，将滤饼在120℃条件下干燥5h，然后在750℃条件下煅烧5h得到最终的产物。在干燥及煅烧过程中，全部用氮气气氛进行保护，制得所述的铈锆固溶体1-1#。
实施例2铈锆镧钇的铈锆固溶体1#-2～1#-9的制备
按照实施例1的铈锆固溶体1#-1的原料与制备方法，改变Ce 3+与过氧化氢的摩尔比分别制备铈锆固溶体1#-2～1#-8，铈锆固溶体1#-1～1#-8的具体的摩尔比和制得的铈锆固溶体1#-1～1#-8的Ce 3+/Ce 4+的摩尔比如表1所示。
按照实施例1的铈锆固溶体1#-1的原料与制备方法，将原料Ce 3+替换为Ce 4+，步骤中不加入双氧水，制备铈锆固溶体1#-9。
Ce 3+/Ce 4+的摩尔比使用XPS进行测试，其中，以铈锆固溶体1#-1、1#-4、1#-8的XPS图谱图1、图2、图3为例，说明Ce 3+/Ce 4+的测试图谱结果。从图1-3可知，铈锆固溶体1#-1、1#-4和1#-8同时包含Ce 3+/Ce 4+及其含量。
表1
Figure PCTCN2019102760-appb-000001
实施例3铈锆镧镨的铈锆固溶体2#-1的制备
包括铈、锆、镧和镨的铈锆固溶体2#-1，铈锆固溶体2#-1按氧化铈、氧化锆、氧化镧、氧化镨的氧化物重量记比例为：20wt％氧化铈，73wt％氧化锆，2wt％氧化镧，5wt％氧化镨。
铈锆固溶体2#-1的制备方法包括下述步骤(过氧化氢摩尔量为Ce 3+离子摩尔量的1.3倍)：
1)在第一个烧杯中，将140g氧化铈对应的硝酸亚铈溶于500mL去离子水中,搅拌1h；第二个烧杯中，加入511g氧化锆对应的硝酸锆,并用1000mL去离子水溶解,搅拌1h；在第三个烧杯中，将14g氧化镧对应的硝酸镧及35g氧化钇对应的硝酸钇用1000mL去离子水溶解，溶液搅拌至 澄清。
2)将三个烧杯中的溶液混合，搅拌至澄清，在40℃水浴条件下用氨水调节PH至2.0，此时溶液为清液，加入119.9g浓度30％的过氧化氢，搅拌2h，无沉淀生成。将溶液定容至7L，并引入至10L搪瓷水热合成釜中，反应釜上方用氮气密封，180℃水热20h，将水热后的产物用氨水调节PH在9-10之间，将调完PH后的物料在40℃水浴温度下老化3h。
3)将老化后的物料引入至高压反应釜中，在180℃水热10h；反应后的产物并加入300g月桂酸，搅拌30分钟，然后抽滤，将滤饼在120℃条件下干燥5h，然后在750℃条件下煅烧5h得到最终的产物。在干燥及煅烧过程中，全部用氮气气氛进行保护，制得所述的铈锆固溶体2#-1。
实施例4铈锆镧钇的铈锆固溶体2#-2～2#-8的制备
按照实施例3的铈锆固溶体2#-1的原料与制备方法，改变Ce 3+与过氧化氢的摩尔比分别制备铈锆固溶体2#-2～2#-8，铈锆固溶体2#-1～2#-8的具体的摩尔比和制得的铈锆固溶体2#-1～2#-8的Ce 3+/Ce 4+的摩尔比如表2所示。
按照实施例3的铈锆固溶体2#-1的原料与制备方法，将原料Ce 3+替换为Ce 4+，步骤中不加入双氧水，制备铈锆固溶体2#-9。
Ce 3+/Ce 4+的摩尔比使用XPS进行测试，其中，以铈锆固溶体2#-1、2#-4的XPS图谱图4、图5为例，说明Ce 3+/Ce 4+的测试图谱结果。从图4、图5可知，铈锆固溶体2#-1、2#-4同时包含Ce 3+/Ce 4+及其含量。
表2
Figure PCTCN2019102760-appb-000002
Figure PCTCN2019102760-appb-000003
实施例5铈锆固溶体1#-1～1#-9、2#-1～2#-9的比表面积、储氧量测试
分别测试实施例1-4制得的铈锆固溶体1#-1～1#-8、2#-1～2#-8的比表面积、在1100℃老化4h后的比表面积、经750℃-4h处理储氧量和经1100℃-4h处理储氧量，测试结果如表3所示。
表3
Figure PCTCN2019102760-appb-000004
Figure PCTCN2019102760-appb-000005
Figure PCTCN2019102760-appb-000006
由表3可知，Ce 3+/Ce 4+的比例在0.1-0.5之间的铈锆固溶体1#-6、铈锆固溶体2#-6经过750℃，4h处理后储氧量不低于561μmol[O]/g；铈锆固溶体1#-6、2#-6在1100℃处理4h的比表面积不低于35m 2/g。铈锆固溶体1#-2经过750℃，4h处理后储氧量高达656μmol[O]/g；铈锆固溶体1#-1在1100℃处理4h的比表面积高达40m 2/g。铈锆固溶体1#-2在1100℃处理4h的储氧量可达623μmol[O]/g。Ce 3+/Ce 4+的比例在0.1-0.5之间的铈锆固溶体1#-6、铈锆固溶体2#-6时表现出了更优异的储氧性能，说明其具有更加稳定的晶体结构。
实施例6催化剂1#-1～1#-9、2#-1～2#-9的制备
利用等体积浸渍法将催化活性组分钯分别负载于铈锆固溶体1#-1～1#-9、2#-1～2#-9制得催化剂1#-1～1#-9、2#-1～2#-9，催化剂1#-1～1#-9、2#-1～2#-9的钯的负载量相同都为1.5wt％。
以铈锆固溶体1#-1为例说明具体的负载方法，其包括：以氯钯酸溶液(H 2PdCl 4)为前驱体浸渍液，对铈锆固溶体1#-1浸渍负载，负载量为1.5wt％；负载后的浆液在旋转蒸发仪中干燥，然后置于110℃的鼓风干燥箱中干燥3h，再置于煅烧炉中在空气气氛中500℃煅烧3小时。
实施例7催化剂1#-1～1#-9、2#-1～2#-9对CO的催化性能测试
400℃取点，分别测试催化剂1#-1～1#-9、2#-1～2#-9对不同λ下CO转化率如表4所示，由表4中数据可以看出，Ce 3+/Ce 4+的比例在0.1-0.7之间时，催化剂对CO有较高的催化活性；Ce 3+/Ce 4+的比例在0.1-0.5之间时，催化剂对CO有更高的催化活性；并且催化剂的适用的λ值范围大。
表4
Figure PCTCN2019102760-appb-000007
实施例8催化剂1#-1～1#-9、2#-1～2#-9对C 2H 6的催化性能测试
400℃取点，分别测试催化剂1#-1～1#-9、2#-1～2#-9对不同λ下C 2H 6 转化率如表5所示，由表5中数据可以看出，Ce 3+/Ce 4+的比例在0.1-0.7之间时，催化剂对C 2H 6有较高的催化活性；Ce 3+/Ce 4+的比例在0.1-0.5之间时，催化剂对C 2H 6有更高的催化活性；并且催化剂的适用的λ值范围大。
表5
Figure PCTCN2019102760-appb-000008
实施例9催化剂1#-1～1#-8、2#-1～2#-8对NO 2的催化性能测试
400℃取点，分别测试催化剂1#-1～1#-9、2#-1～2#-9对不同λ下NO 2 转化率如表6所示，由表6中数据可以看出，Ce 3+/Ce 4+的比例在0.1-0.7之间时，催化剂对NO 2有较高的催化活性；Ce 3+/Ce 4+的比例在0.1-0.5之间时，催化剂对NO 2有更高的催化活性；并且催化剂的适用的λ值范围大。
表6
Figure PCTCN2019102760-appb-000009
实施例10老化催化剂1#-1～1#-8制备
分别将铈锆固溶体1#-1～1#-8在1100℃，4h老化处理后得到老化铈 锆固溶体1#-1～1#-8，利用实施例6的负载方法将将相同量的钯负载在老化铈锆固溶体1#-1～1#-8制得老化催化剂1#-1～1#-8。
实施例11老化催化剂1#-1～1#-8对NO 2催化性能测试
400℃取点，老化催化剂1#-1～1#-8对不同λ下NO 2转化率如表7所示，由表7中数据可以看出，Ce 3+/Ce 4+的比例在0.1-0.7之间时，老化催化剂1#-1～1#-8对NO 2有较高的催化活性；Ce 3+/Ce 4+的比例在0.1-0.5之间时，老化催化剂1#-1～1#-8对NO 2有更高的催化活性，说明Ce 3+/Ce 4+的比例在0.1-0.5之间时，便显出了更好的结构稳定性。
表7
Figure PCTCN2019102760-appb-000010
以上所述，仅为本申请的实施例而已，本申请的保护范围并不受这些具体实施例的限制，而是由本申请的权利要求书来确定。对于本领域技术人员来说，本申请可以有各种更改和变化。凡在本申请的技术思想和原理之内所作的任何修改、等同替换、改进等，均应包含在本申请的保护范围之内。

Claims (10)

  1. 一种铈锆固溶体，其特征在于，所述铈锆固溶体包括铈锆固溶体相，所述铈锆固溶体相包含三价铈离子和四价铈离子，所述三价铈离子和四价铈离子的摩尔比为0.05-0.8:1。
  2. 根据权利要求1所述的铈锆固溶体，其特征在于，所述三价铈离子和四价铈离子的摩尔比为0.1-0.5:1。
  3. 根据权利要求1所述的铈锆固溶体，其特征在于，所述铈锆固溶体包括重量比为20-50:20-80:2-20的铈的氧化物、ZrO 2、第一稀土元素氧化物；
    所述第一稀土元素选自除铈外的稀土元素、过渡金属元素和碱土金属元素中的至少一种；
    优选地，所述第一稀土元素选自镧、钇、镨、钕和钐中的至少一种。
  4. 根据权利要求3所述的铈锆固溶体，其特征在于，所述铈锆固溶体还包括第二稀土元素氧化物，所述铈的氧化物与第二稀土元素氧化物的重量比为20-50：2-5；
    所述第二稀土元素选自钷、钐、铕、钆、铽、镝、钬、铒、铥、镱、镥和钪中的至少一种。
  5. 根据权利要求3所述的铈锆固溶体，其特征在于，所述铈锆固溶体包括重量比为25-45:30-70:3-15:2-4的铈的氧化物、ZrO 2、第一稀土元素氧化物和第二稀土元素氧化物。
  6. 根据权利要求1所述的铈锆固溶体，其特征在于，所述铈锆固溶体经过850℃煅烧4h后，储氧量不低于540μmol[O]/g；和/或
    所述铈锆固溶体在1100℃处理4h的比表面积不低于30m 2/g。
  7. 权利要求1-6中任一项所述的铈锆固溶体的制备方法，其特征在 于，其包括下述步骤：
    1)混料：配制包含三价铈离子和锆离子的水溶液的初混物；
    2)氧化反应：根据需要的三价铈离子和四价铈离子量向酸性的初混物中加入过氧化氢，加入沉淀剂调节溶液的pH为10-11，制得前驱体溶液；
    3)第一水热反应：将前驱体溶液进行第一水热反应后，在非活性气体中焙烧，即制得所述的铈锆固溶体；
    优选地，所述步骤1)混料包括步骤：配置包含三价铈离子、锆离子和M离子的水溶液的初混物；
    优选地，所述步骤2)包括下述步骤：
    ①向初混物中加入碱性沉淀剂至溶液pH为1.0-2.5；根据需要的三价铈离子和四价铈离子量向酸性的初混物中加入30％的过氧化氢水溶液，搅拌至少1h，进行第二水热反应；和
    ②加入沉淀剂调节溶液的pH为10-11，老化至少1h，制得前驱体溶液；
    优选地，所述步骤3)中的焙烧的条件为在非活性气体中750℃-850℃焙烧4h。
  8. 根据权利要求7所述的铈锆固溶体的制备方法，其特征在于，所述铈锆固溶体包括20wt％-60wt％铈的氧化物和35wt％-60wt％ZrO 2，所述铈的氧化物包括摩尔比为0.05-0.7:1的三价铈离子和四价铈离子。
  9. 一种催化剂，其特征在于，所述催化剂包含铈锆固溶体，所述铈锆固溶体选自：
    权利要求1-6中任一项所述的铈锆固溶体或，由权利要求7或8所述的方法制得的铈锆固溶体，或
    权利要求1-6中任一项所述的铈锆固溶体经500-1200℃焙烧至少1h 或，由权利要求7或8所述的方法制得的铈锆固溶体经500-1200℃焙烧至少1h。
  10. 权1-6的铈锆固溶体或权利要求9所述的催化剂的应用，其特征在于，所述应用选自I或II中的任一种：
    I、催化转化选自CH 4、C 3H 8、C 2H 6、NO 2、NO、CO、H 2O或CO 2中的一种或任意几种气体的应用；
    II、在移动源尾气、废气处理、天然气催化燃烧、有机废气净化处理或工业废气脱硝处理中的应用。
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