Cu-ce-zr catalyst for reverse water gas shift reaction and preparation method and application thereof

Abstract

The application discloses a Cu-Ce-Zr catalyst for reverse water gas shift reaction and a preparation method and application thereof, and comprises Cu, Ce and Zr and is prepared according to the following mass percentage: Zr 0.1% to 90%; Ce 0.1% to 10%; and Cu 0% to 15%. The Cu-Ce-Zr catalyst is used in a dielectric barrier discharge plasma reactor, and the Cu-Ce-Zr catalyst has the characteristics of oxygen-rich vacancies and highly dispersed copper. The application obtains a catalyst with excellent stability. In the reverse water gas shift reaction, the carbon monoxide selectivity reaches nearly 100%. In the plasma reactor, under the condition of low temperature and normal pressure, the catalyst shows excellent catalytic activity and stability in the reverse water gas shift reaction.

Description

Technical Field

[0001] This invention relates to the field of catalysts that can be used in reverse water-gas shift reactions in plasma-enhanced catalytic DBD reactors, and particularly to a Cu-Ce-Zr catalyst for reverse water-gas shift reactions, its preparation method, and its application. Background Technology

[0002] Since the Industrial Revolution, global atmospheric CO2 concentration has increased dramatically, which will lead to a 1.5°C rise in the world's average temperature over the next two to three decades (US EPA, 2017). This poses a huge threat to the environment on which we depend for survival and a significant challenge to the development of contemporary society. Governments around the world have also proposed corresponding "carbon neutrality" targets to reduce atmospheric CO2 levels (Álvarez Galván et al., 2016; C.-S. Chen et al., 2000; Fujita et al., 1992). Converting CO2 into high-value-added chemicals is an effective way to reduce atmospheric CO2 levels (He et al., 2013). In CO2 chemical conversion reactions, the reverse water-gas shift reaction (RWGS, CO2 + H2 → CO + H2O, ΔH...). 0，298 =+41 kJ mol −1 RWGS is a representative reaction. Its main advantage is that the product is CO, which can be used as a base material for other processes such as Fischer-Tropsch synthesis and methanol synthesis. (Daza & Kuhn, 2016) Since the RWGS reaction is endothermic, it typically requires high temperature and high pressure to achieve considerable reaction efficiency.

[0003] In this research field, scholars are dedicated to studying low-cost heterogeneous catalysts and novel catalytic methods to reduce reaction temperature and pressure, thereby achieving greater economic efficiency. Currently, research primarily focuses on the development of transition metal catalysts. Copper-based catalysts and CeO2-supported catalysts are representative examples. Copper-based catalysts have attracted significant attention due to their excellent catalytic activity and stability in CO synthesis. A unique characteristic of Cu is that CC coupling is difficult to occur on copper-based catalysts (Christensen et al., 2022), highlighting the potential of copper-based catalysts in C1 product production. Due to the nano-effect, the physical size of copper nanoparticles also profoundly influences catalytic performance (Karelovic & Ruiz, 2015). However, due to the low Tammann temperature (407℃) of copper and its lack of sufficient thermal stability, copper nanoparticles in traditional industrial catalysts such as Cu / ZnO / Al2O3 can sinter through surface migration under high-temperature conditions, a process further accelerated, especially in the presence of water. (Li et al., 2022) The aforementioned drawbacks have severely limited the industrial application of copper-based catalysts. Therefore, reducing the reaction temperature of copper-based catalysts has become a key research focus for scholars.

[0004] Previous studies (Ning et al., 2021, 2023) have shown that oxygen vacancies on catalysts can effectively promote CO2 activation at low temperatures, and CeO2, by providing oxygen vacancies, is a good support material for CO2 reduction reactions. (Wang et al., 2016) Wang and colleagues explored the reaction mechanism of CO2 hydrogenation on Ru / CeO2 (with oxygen vacancies) and Ru / Al2O3 (without oxygen vacancies). Because oxygen vacancies on the CeO2 surface act as active sites to promote CO2 conversion, catalysts with oxygen vacancies exhibit stronger CO2 reduction capabilities and lower reduction temperatures compared to catalysts without oxygen vacancies. (Wang et al., 2016) The academic community typically introduces zirconium ions into the CeO2 lattice to increase the generation of oxygen vacancies and improve catalyst stability. (Fornasiero et al., 1995) Compared with pure CeO2, the cerium-zirconium solid solution (CZO) formed by CeO2 and ZrO2 can enhance the metal-support interaction, exhibiting better catalytic reduction activity and better stability. (Le et al., 2017; Razzaq et al., 2013) Based on the above reasons, this study focuses on the application of catalysts composed of Cu as the active metal and CeO2-ZrO2 (CZO) as the support in the RWGS reaction.

[0005] In addition, due to the significant advantages of NTPs in activating thermodynamically stable molecules (such as CO2) (Mei et al., 2016; Yi et al., 2013), the process of enhancing the catalytic conversion of CO2 using nonthermal plasma (NTP) methods has attracted great attention from the academic community (Bogaerts & Centi, 2020). NTP-enhanced catalysis technology is expected to overcome the thermodynamic limitations of the reverse water-gas shift reaction, and the macroscopic temperature of NTP is close to room temperature, which is also expected to overcome the high energy consumption problem of the RWGS reaction (Fridman, 2008). Mei et al. studied the NTP-enhanced catalytic conversion of CO2 to CO without an external heating source, and the results showed that the CO2 conversion rate was 22.6%, proving that NTP can play a promoting role in the catalytic conversion of CO2 (Ray & Subrahmanyam, 2016). Ray et al. studied the NTP-enhanced catalytic CO2 hydrogenation reaction and proved that Cu-based catalysts, compared with other transition metals, help to improve the efficiency of CO2 hydrogenation reaction. (Ray et al., 2021) Chen et al.'s report confirmed that oxygen vacancies on the support play an important role in the enhanced catalytic CO2 conversion reaction by NTP. (G. Chen et al., 2016) The above studies have demonstrated that Cu-based catalysts and NTPs can achieve efficient CO2 hydrogenation, and the introduction of oxygen vacancies may improve catalytic efficiency.

[0006] Therefore, the low thermal stability and easy sintering of copper-based catalysts remain technical problems that need to be solved, and new ideas for CO2 hydrogenation conversion are needed. Summary of the Invention

[0007] The purpose of this invention is to provide a Cu-Ce-Zr catalyst for reverse water-gas shift reaction, its preparation method, and its application.

[0008] The solution of the present invention is:

[0009] This invention discloses a Cu-Ce-Zr catalyst for reverse water-gas shift reaction, comprising Cu, Ce, and Zr, prepared according to the following mass percentages:

[0010] Zr 0.1%~90%;

[0011] Ce 0.1%~10%;

[0012] Cu 0%~15%;

[0013] The Cu-Ce-Zr catalyst, when used in a dielectric barrier discharge plasma reactor, demonstrates its characteristics of being rich in oxygen vacancies and having highly dispersed copper.

[0014] As a preferred technical solution, the molar ratio of Ce to Zr is 1:10.

[0015] This invention also discloses a method for preparing a Cu-Ce-Zr catalyst for reverse water-gas shift reaction, comprising the following steps:

[0016] 1) Dissolve Ce(NO3)3·6H2O and Zr(NO3)4·5H2O precursors in deionized water at a molar ratio of 1:10 to prepare solution A;

[0017] 2) Dissolve the Cu(NO3)2·3H2O precursor in deionized water to obtain solution B;

[0018] 3) Dissolve KHCO3 in deionized water to form a 0.06M solution C;

[0019] 4) Use a peristaltic pump to slowly add solution A and solution B dropwise into solution C, heat at 80°C, stop stirring after the addition is complete, and age for 24 hours;

[0020] 5) Cool to room temperature, wash K ions with deionized water, and then dry in an oven at 80°C to obtain the catalyst precursor;

[0021] 6) The catalyst precursor was calcined at 550-700°C for 240-360 minutes at a heating rate of 2°C / min, and then naturally cooled to room temperature. It was then transferred to a furnace and calcined at 350°C from room temperature to 2°C / min for 6 hours, and then naturally cooled to obtain the Cu-Ce-Zr catalyst.

[0022] As a preferred technical solution, the mass percentages of Cu, Ce and Zr are a:b:c = 0%~15%:0.1%~10%:0.1%~90%.

[0023] The present invention also discloses the application of a Cu-Ce-Zr catalyst for a reverse water-gas shift reaction, wherein the catalyst is applied to a plasma-enhanced catalytic reverse water-gas shift reaction.

[0024] As a preferred technical solution, the catalyst is used in the reverse water-gas shift reaction in a dielectric barrier discharge (DBD) plasma reactor. The catalyst is disposed in the discharge region of the dielectric barrier discharge (DBD) plasma reactor, the reaction temperature is 60 degrees Celsius, and the reaction pressure is atmospheric pressure. Through the discharge of the plasma reactor, a CO2 conversion rate of over 30% and a CO selectivity of nearly 100% are obtained in the reverse water-gas shift reaction.

[0025] The above-mentioned technical solution is used to develop a Cu-Ce-Zr catalyst for reverse water-gas shift reaction, its preparation method, and its application. The catalyst comprises the following steps: 1) Dissolving Ce(NO3)3·6H2O and Zr(NO3)4·5H2O precursors in deionized water at a molar ratio of 1:10 to prepare solution A; 2) Dissolving the Cu(NO3)2·3H2O precursor in deionized water to obtain solution B; 3) Dissolving KHCO3 in deionized water to form a 0.06M solution C; 4) Using a peristaltic pump to pump the solution... A and solution B are slowly added dropwise to solution C, heated at 80°C, and stirring is stopped after the addition is complete. The mixture is aged for 24 hours. 5) The mixture is cooled to room temperature, K ions are washed with deionized water, and then dried in an oven at 80°C to obtain the catalyst precursor. The catalyst precursor is calcined at 550-700°C for 240-360 minutes at a heating rate of 2°C / min, and then naturally cooled to room temperature. It is then transferred to a furnace and calcined at 350°C from room temperature to 2°C / min for 6 hours. After natural cooling, the Cu-Ce-Zr catalyst is obtained.

[0026] The beneficial effects of this invention are:

[0027] This invention fully leverages the advantages of Cu-based catalysts, oxygen vacancy supports, and nonthermal plasma (NTP) methods, and utilizes RWGS reactions as probe reactions to prepare catalysts that are more cost-effective, more stable, and exhibit high selectivity and activity. This provides a new approach for CO2 hydrogenation conversion. It solves the problems of low thermal stability and easy sintering inherent in copper-based catalysts, and this catalyst possesses better catalytic reduction activity and stability due to enhanced metal-support interactions.

[0028] The catalyst of this invention achieves near 100% carbon monoxide (CO) selectivity in the reverse water-gas shift reaction by employing a dielectric barrier discharge (DBD) plasma reactor. Under low temperature and atmospheric pressure conditions, this catalyst exhibits excellent catalytic activity and stability in the reverse water-gas shift reaction.

[0029] In summary, the catalyst of this invention has the characteristics of low reaction energy consumption, high conversion rate, near 100% CO selectivity and good stability in the NTP-enhanced reverse water-gas shift reaction. Attached Figure Description

[0030] Figure 1 This is a graph showing the catalytic performance of the catalyst prepared in Example 1 of the present invention.

[0031] Figure 2 This is an HR-TEM image of Embodiment 1 of the present invention.

[0032] Figure 3 This is the XRD pattern of Embodiment 1 of the present invention.

[0033] Figure 4 EPR diagram of Embodiment 1 of the present invention

[0034] Figure 5 This is the O 1s XPS image of Embodiment 1 of the present invention.

[0035] Figure 6 This is the in-situ CCD spectrum of Embodiment 1 of the present invention.

[0036] Figure 7 This is a catalytic stability test diagram of Example 1 of the present invention. Detailed Implementation

[0037] This invention provides a Cu-Ce-Zr catalyst for reverse water-gas shift reaction, its preparation method, and its application.

[0038] This invention synthesizes a catalyst using KHCO3 as a precipitant via a co-precipitation method. First, Ce(NO3)3·6H2O (Adamas, 99.99%) and Zr(NO3)4·5H2O (Adamas, 99.99%) precursors were weighed, with a Ce to Zr molar ratio of 1:10. These were dissolved together in 50 mL of deionized water to prepare solution A. Based on the metal loading, an appropriate amount of Cu(NO3)2·3H2O (Adamas, 99.99%) was weighed and dissolved in 50 mL of deionized water to prepare solution B. An appropriate amount of KHCO3 (Adamas, 99.99%) was weighed and dissolved in 200 mL of deionized water to prepare a 0.06 M solution (solution C). Solutions A and B were slowly added dropwise to solution C using a peristaltic pump at a flow rate of 20 mL / min. Throughout the addition process, the mixture was heated at 80°C. After the addition was complete, stirring was stopped, and the resulting flocculent precipitate was aged at 80℃ for 24 hours. After aging, it was cooled to room temperature, washed with 2L of deionized water to remove K ions, and then dried overnight in an oven at 80℃. Finally, the catalyst was calcined at 550℃ for 240 minutes (heating rate 2℃ / min).

[0039] The catalytic performance of all catalysts was tested in the DBD reactor described later. 1500 mg of Cu / CZO catalyst (20-40 mesh) was placed in a quartz boat and placed in a tube furnace (Shanghai Ruijing Machinery Equipment Co., Ltd., RGG1200-60) with H2 flowing at a rate of 30 ml / min for 30 minutes. It was then pretreated with H2 at 350 °C (heating rate 2 °C / min) at a flow rate of 100 ml / min for 5 hours. After cooling to room temperature, the catalyst was introduced into the reactor for a series of subsequent reactions.

[0040] The plasma quartz reactor used in the embodiments listed below includes an aluminum rod, a quartz glass tube, and copper wire electrodes. A solid aluminum rod with a diameter of 16.0 mm and a length of 400 mm serves as the high-voltage electrode of the reactor, located concentrically with the quartz tube at the center of the reactor. Copper wire, serving as the low-voltage electrode, is wound around the outer wall of the quartz tube in 25 turns. The barrier medium is a 400 mm long transparent quartz tube with a relative permittivity of 3.7, an outer diameter of 25 mm, and an inner diameter of 22 mm. The air gap between the aluminum rod and the quartz tube is 2 mm. Discharge parameters of the plasma reactor are acquired using a high-voltage probe (P6015A Voltage Probe, Tektronix) and displayed and recorded on a digital oscilloscope (TDS-2024C, Tektronix). Two high-voltage probes are used to acquire data: one directly connected to the power output and the reactor's high-voltage electrode, and the other connected to the reactor's low-voltage and ground electrodes via a measuring capacitor (C=0.47 μF). These two probes are used to acquire signals for calculating key reactor parameters. The input gas consisted of a mixture of high-pressure CO2 and H2, with the flow rate controlled by a mass flow meter at a ratio of 1:3. The mixed gas was introduced into each catalytic system configuration at a flow rate of 30 mL / min for evaluation. The configuration was In-plasma Configuration (IPC), where the catalyst was positioned within the DBD discharge region. The reaction apparatus placed the catalyst within the aforementioned plasma reactor discharge region, with asbestos used to fix the catalyst at both ends to ensure complete filling of the discharge region. The position of the catalyst was secured with asbestos, and plasma simultaneously irradiated both the catalyst and the reactant gas. The reaction temperature was 60 degrees Celsius (heat generated only by plasma discharge, with no external heating source). The products were analyzed using gas chromatography.

[0041] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments. Example 1

[0042] Step 1: Prepare a precursor solution of Ce(NO3)3·6H2O (Adamas, 99.99%) and Zr(NO3)4·5H2O (Adamas, 99.99%), with a molar ratio of Ce to Zr of 1:10. Dissolve them together in 50 ml of deionized water to prepare solution A. Weigh out Cu(NO3)2·3H2O (Adamas, 99.99%) with a Cu mass percentage of 7% and dissolve it in 50 ml of deionized water to prepare solution B.

[0043] Step 2: Weigh an appropriate amount of KHCO3 (Adamas, 99.99%) and dissolve it in 200 ml of deionized water to prepare a 0.06 M solution (solution C). Using a peristaltic pump, slowly add solutions A and B dropwise to solution C at a flow rate of 20 mL / min. During the entire addition process, heat the mixture at 80°C. After the addition is complete, stop stirring and age the resulting flocculent precipitate at 80°C for 24 h. After aging, cool it to room temperature, wash away the K ions with 2 L of deionized water, and then dry it overnight in an oven at 80°C.

[0044] Step 3: The catalyst precursor is placed in a muffle furnace and calcined at a heating rate of 2℃ / min from room temperature to 550℃ for 6 hours. After natural cooling to room temperature, the catalyst is transferred to a tube furnace and a 10% H2 / He mixed gas is introduced. The temperature is then increased from room temperature to 350℃ at a heating rate of 2℃ / min for 6 hours. After natural cooling to room temperature, the catalyst is introduced into a reactor. The final catalyst obtained is named 7wt%Cu / CZO.

[0045] Catalyst Application: The prepared 7wt% Cu / CZO was applied to a reverse water-gas shift reaction. The catalyst was pressed into tablets and ground to a size of 40-80 mesh. 1.5 μL of the tablets were used to fill a quartz tube reactor. Reactant gases were introduced at atmospheric pressure with a hydrogen:carbon dioxide molar ratio of 3:1. The reaction temperature was 60℃ (heat generated only by plasma discharge, without an external heating source), and the gas flow rate was 30 mL / min. The CO2 conversion rate was 37.76%, and the CO selectivity was 97.58%.

[0046] This invention utilizes copper-cerium-zirconium oxide nanoparticles formed by a co-precipitation method, which exhibit high stability and a large surface area, enabling them to capture a significant amount of CO2. Simultaneously, the introduction of transition metal elements such as Cu and oxygen vacancy generators such as CeO2 results in a large number of active sites on the catalyst. Furthermore, the enhancement of these active sites by plasma leads to a high conversion rate. In addition, the catalyst of this invention is simple to prepare, environmentally friendly, and the catalytic process is carried out at low temperature and normal pressure, requiring minimal equipment and ensuring safety and environmental friendliness.

[0047] The catalyst of this invention can be applied to the catalytic hydrogenation of CO2 to CO in a reverse water-gas shift reaction. The reaction conditions for catalytic CO2 hydrogenation to CO are: a mixture of CO2 and H2 as reactants, with an H2 / CO2 volume ratio of 2.0–5.0; a reaction temperature of 60°C; atmospheric pressure; and a gas flow rate of 30 mL / min. After optimization, the final CO2 conversion rate reaches 38%, and the CO selectivity is very close to 100%. Example 2

[0048] 1) Dissolve the precursors Ce(NO3)3·6H2O and Zr(NO3)4·5H2O in deionized water to prepare solution A;

[0049] 2) Dissolve the Cu(NO3)2·3H2O precursor in deionized water to obtain solution B;

[0050] 3) Dissolve KHCO3 in deionized water to form a 0.06M solution C;

[0051] 4) Use a peristaltic pump to slowly add solution A and solution B dropwise into solution C, heat at 80°C, stop stirring after the addition is complete, and age for 24 hours;

[0052] 5) Cool to room temperature, wash K ions with deionized water, and then dry in an oven at 80°C to obtain the catalyst precursor;

[0053] 6) The catalyst precursor was calcined at 700°C for 240–360 minutes at a heating rate of 2°C / min, then naturally cooled to room temperature. It was then transferred to a furnace and calcined at 350°C from room temperature to 2°C / min for 6 hours, followed by natural cooling to obtain the Cu-Ce-Zr catalyst.

[0054] The mass percentages of Cu, Ce, and Zr are a:b:c = 1%:9%:90%. Example 3

[0055] Dissolve the precursors Ce(NO3)3·6H2O and Zr(NO3)4·5H2O in deionized water to prepare solution A;

[0056] Dissolve the Cu(NO3)2·3H2O precursor in deionized water to obtain solution B;

[0057] KHCO3 was dissolved in deionized water to form a 0.06M solution C;

[0058] Using a peristaltic pump, slowly add solutions A and B dropwise to solution C, heat at 80°C, stop stirring after the addition is complete, and age for 24 hours;

[0059] Cool to room temperature, wash K ions with deionized water, and then dry in an oven at 80°C to obtain the catalyst precursor;

[0060] The catalyst precursor was calcined at 700°C for 240–360 minutes at a heating rate of 2°C / min, then naturally cooled to room temperature. It was then transferred to a furnace and calcined at 350°C from room temperature to 2°C / min for 6 hours, followed by natural cooling to obtain the Cu-Ce-Zr catalyst.

[0061] The mass percentages of Cu, Ce, and Zr are a:b:c = 15%:1%:84%.

[0062] Comparison Example 1

[0063] As a control group, a similar synthesis method to that in Example 1 was used, except that the loading of the active metal Cu was modified to verify the optimal loading of Cu.

[0064] Step 1: Prepare a precursor solution of Ce(NO3)3·6H2O (Adamas, 99.99%) and Zr(NO3)4·5H2O (Adamas, 99.99%), with a molar ratio of Ce to Zr of 1:10. Dissolve them together in 50 ml of deionized water to prepare solution A. Weigh out Cu(NO3)2·3H2O (Adamas, 99.99%) with a Cu mass percentage of 3% and dissolve it in 50 ml of deionized water to prepare solution B.

[0065] Step 2: Weigh an appropriate amount of KHCO3 (Adamas, 99.99%) and dissolve it in 200 ml of deionized water to prepare a 0.06 M solution (solution C). Using a peristaltic pump, slowly add solutions A and B dropwise to solution C at a flow rate of 20 mL / min. During the entire addition process, heat the mixture at 80°C. After the addition is complete, stop stirring and age the resulting flocculent precipitate at 80°C for 24 h. After aging, cool it to room temperature, wash away the K ions with 2 L of deionized water, and then dry it overnight in an oven at 80°C.

[0066] Step 3: The catalyst precursor is placed in a muffle furnace and calcined at 550°C for 6 hours at a heating rate of 2°C / min. After natural cooling to room temperature, the catalyst is transferred to a tube furnace and a 10% H2 / He mixed gas is introduced. The temperature is then increased from room temperature to 350°C for 6 hours at a heating rate of 2°C / min. After natural cooling to room temperature, the catalyst is introduced into a reactor. The final catalyst obtained is named 3wt%Cu / CZO.

[0067] Catalyst Application: The prepared 3wt% Cu / CZO was applied to a reverse water-gas shift reaction. The catalyst was pressed into tablets and ground to a size of 40-80 mesh. 1.5 μL of the tablets were used to fill a quartz tube reactor. Reactant gases were introduced at atmospheric pressure with a hydrogen:carbon dioxide molar ratio of 3:1. The reaction temperature was 60℃ (heat generated only by plasma discharge, without an external heating source), and the gas flow rate was 30 mL / min. The CO2 conversion rate was 12.68%, and the CO selectivity was 98.76%.

[0068] Comparison Example 2

[0069] As a control group, a similar synthesis method to that in Example 1 was used, except that the loading of the active metal Cu was modified to verify the optimal loading of Cu.

[0070] Step 1: Prepare a precursor solution of Ce(NO3)3·6H2O (Adamas, 99.99%) and Zr(NO3)4·5H2O (Adamas, 99.99%), with a molar ratio of Ce to Zr of 1:10. Dissolve them together in 50 ml of deionized water to prepare solution A. Weigh out Cu(NO3)2·3H2O (Adamas, 99.99%) with a Cu mass percentage of 15% and dissolve it in 50 ml of deionized water to prepare solution B.

[0071] Step 2: Weigh an appropriate amount of KHCO3 (Adamas, 99.99%) and dissolve it in 200 ml of deionized water to prepare a 0.06 M solution (solution C). Using a peristaltic pump, slowly add solutions A and B dropwise to solution C at a flow rate of 20 mL / min. During the entire addition process, heat the mixture at 80°C. After the addition is complete, stop stirring and age the resulting flocculent precipitate at 80°C for 24 h. After aging, cool it to room temperature, wash away the K ions with 2 L of deionized water, and then dry it overnight in an oven at 80°C.

[0072] Step 3: The catalyst precursor is placed in a muffle furnace and calcined at a heating rate of 2℃ / min from room temperature to 550℃ for 6 hours. After natural cooling to room temperature, the catalyst is transferred to a tube furnace and a 10% H2 / He mixed gas is introduced. The temperature is then increased from room temperature to 350℃ at a heating rate of 2℃ / min for 6 hours. After natural cooling to room temperature, the catalyst is introduced into a reactor. The final catalyst obtained is named 7wt%Cu / CZO.

[0073] Catalyst Application: The prepared 3wt% Cu / CZO was applied to a reverse water-gas shift reaction. The catalyst was pressed into tablets and ground to a size of 40-80 mesh, and 1.5 mm was used to fill a quartz tube reactor. Reactant gas was introduced at atmospheric pressure with a hydrogen:carbon dioxide molar ratio of 3:1. The reaction temperature was 60℃ (heat generated only by plasma discharge, without an external heating source), and the gas flow rate was 30 mL / min. The CO2 conversion rate was 25.12%, and the CO selectivity was 99.14%.

[0074] Appendix Figure 1 This is a graph showing the catalytic performance of the catalyst prepared in Example 1 of the present invention.

[0075] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A Cu-Ce-Zr catalyst for reverse water gas shift reaction, characterized by, The components thereof include Cu, Ce and Zr, and are prepared according to the following mass percentages: Zr 0.1%～90%； Ce 0.1%~10%; Cu 0%~15%; The molar ratio of the Ce and Zr is 1:10, and the mass percentage of Cu does not include the 0% end value; The Cu-Ce-Zr catalyst is used in a dielectric barrier discharge plasma reactor, and the characteristics of the Cu-Ce-Zr catalyst have oxygen-rich vacancies and highly dispersed copper; The preparation method of the catalyst includes the following steps: Dissolve Ce(NO3)3·6H2O and Zr(NO3)4·5H2O precursors into deionized water according to a molar ratio of 1:10 to prepare solution A; Dissolve Cu(NO3)2·3H2O precursor in deionized water to obtain solution B; Dissolve KHCO3 in deionized water to form 0.06M solution C; Slowly drop solution A and solution B into solution C using a peristaltic pump, heat at 80°C, stop stirring after the dropping is completed, and age for 24 hours; Cool to room temperature, wash K ions with deionized water, and then dry in an oven at 80°C to obtain a catalyst precursor; Cure the catalyst precursor at a temperature increasing rate of 2°C / min at 550~700°C for 240~360 minutes, naturally cool to room temperature, transfer into a furnace, and cure at a temperature increasing rate of 2°C / min from room temperature to 350°C for 6h, and naturally cool to obtain a Cu-Ce-Zr catalyst.

2. A process for the preparation of Cu-Ce-Zr catalyst for reverse water gas shift reaction as claimed in claim 1, wherein, The preparation method includes the following steps: Dissolve Ce(NO3)3·6H2O and Zr(NO3)4·5H2O precursors into deionized water according to a molar ratio of 1:10 to prepare solution A; Dissolve Cu(NO3)2·3H2O precursor in deionized water to obtain solution B; Dissolve KHCO3 in deionized water to form 0.06M solution C; Slowly drop solution A and solution B into solution C using a peristaltic pump, heat at 80°C, stop stirring after the dropping is completed, and age for 24 hours; Cool to room temperature, wash K ions with deionized water, and then dry in an oven at 80°C to obtain a catalyst precursor; Cure the catalyst precursor at a temperature increasing rate of 2°C / min at 550~700°C for 240~360 minutes, naturally cool to room temperature, transfer into a furnace, and cure at a temperature increasing rate of 2°C / min from room temperature to 350°C for 6h, and naturally cool to obtain a Cu-Ce-Zr catalyst.

3. The method of claim 2, wherein: The mass percentages of Cu, Ce and Zr are a:b:c=0%~15%:0.1%~10%:0.1%~90%.

4. Use of a Cu-Ce-Zr catalyst for the reverse water gas shift reaction according to claim 1, characterized in that: The catalyst is applied to a plasma-enhanced catalytic reverse water gas shift reaction.

5. The use according to claim 4, characterized in that: The catalyst is used in a dielectric barrier discharge plasma reactor for a reverse water gas shift reaction, and the catalyst is arranged in a discharge area of the dielectric barrier discharge plasma reactor, the reaction temperature is 60°C, and the reaction pressure is normal pressure.

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