A method for preparing a catalyst, the product, and its application.

Abstract

This invention relates to the field of catalysts and CO2 hydrogenation to methanol technology, and particularly to a method for preparing a catalyst, a product, and its application. The method for preparing the catalyst of this invention includes the following steps: adding a copper-zinc-aluminum catalyst to an aqueous solution of cerium nitrate, mixing thoroughly, and stirring in a water bath to obtain a mixed solution; adding an alkaline solution of NaBH4 to the mixed solution to react and obtain a precipitate; subjecting the precipitate to ultrasonic treatment, washing, drying, grinding, and calcining to obtain the catalyst. This invention introduces the promoter Ce into the copper-zinc-aluminum catalyst and uses sodium borohydride (NaBH4) for reduction to construct Ce... 4+ / Ce 3+ and Cu 2+ / Cu δ+ / Cu 0 Redox electron pairs are used to establish electron transfer pathways and improve the catalytic performance of CO2 hydrogenation to methanol.

Description

Technical Field

[0001] This invention relates to the field of catalysts and CO2 hydrogenation to methanol technology, and in particular to a method for preparing a catalyst, a product, and its application. Background Technology

[0002] Over the past few decades, the fossil fuels consumed by humankind to meet the needs of economic and social development have ultimately been "returned" to humanity as CO2, causing environmental problems such as rising temperatures, rising sea levels, and extreme weather events. Energy conservation, emission reduction, and sustainable development have become a challenge facing the world. In response to this challenge, my country has actively proposed the goal of "peak carbon and carbon neutrality" to alleviate the global energy, environmental, and climate crisis.

[0003] Using CO2 as a C1 resource and combining it with "green hydrogen" to convert it into high-value-added chemicals—methanol—is an effective way to solve this crisis. It not only achieves a green carbon cycle but also effectively alleviates humanity's dependence on fossil fuels. The core technology for CO2 hydrogenation to methanol lies in the development of highly efficient and stable catalysts. Currently, the catalysts used for CO2 hydrogenation to methanol mainly include: non-precious metal catalysts (primarily Cu-based catalysts) and precious metal catalysts. Non-precious metal catalysts have potential advantages in industrial applications due to their low cost; however, the "seesaw" effect between methanol selectivity and CO2 conversion rate, and the sintering problem caused by lattice migration of Cu components at high temperatures, remain bottlenecks hindering their industrialization. Summary of the Invention

[0004] Based on the above, the present invention provides a method for preparing a catalyst, a product thereof, and its application.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] One of the technical solutions of the present invention is a method for preparing a catalyst, comprising the following steps:

[0007] The copper-zinc-aluminum catalyst was added to an aqueous solution of cerium nitrate, mixed thoroughly, and then stirred in a water bath to obtain a mixed solution.

[0008] An alkaline solution of NaBH4 is added to the mixed solution to react and a precipitate is obtained.

[0009] The precipitate was subjected to ultrasonic treatment, then washed, dried, ground, and calcined to obtain the catalyst.

[0010] The second technical solution of the present invention is a catalyst prepared according to the above preparation method.

[0011] The third technical solution of the present invention is the application of the above-mentioned catalyst in the production of methanol by CO2 hydrogenation.

[0012] The fourth technical solution of this invention is a two-stage catalyst for the hydrogenation of CO2 to methanol, which is prepared by the aforementioned catalyst and a commercially available industrial methanol Cu / ZnO / Al2O3 catalyst. (When the two-stage catalyst is used for the hydrogenation of CO2 to methanol, the aforementioned catalyst (CZA-Ce-0.1NaBH4) is located near the inlet end, and the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst is located near the outlet end).

[0013] The present invention discloses the following technical effects:

[0014] This invention constructs Ce by introducing the promoter Ce into a copper-zinc-aluminum catalyst and reducing it with sodium borohydride (NaBH4). 4+ / Ce 3+ and Cu 2+ / Cu δ+ / Cu 0 Redox electron pairs are used to establish electron transfer pathways, improving the catalytic performance of CO2 hydrogenation to methanol. Furthermore, the introduction of Ce can modulate the catalyst's acidity / basicity and provide abundant oxygen vacancies, which is beneficial for the efficient activation and hydrogenation conversion of CO2. This invention uses NaBH4 reduction treatment to introduce more Ce into the catalyst. 4+ / Ce 3+ The redox electron pair improves the electron transfer efficiency within the catalyst, further enhancing the catalytic performance of CO2 hydrogenation to methanol. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 The catalytic performance (a), CO2 conversion at 3 MPa (b), methanol selectivity at 3 MPa (c), CO2 conversion at 4 MPa (d), and methanol selectivity at 4 MPa (e) of the catalysts prepared in Example 1 and Comparative Example 1 of this invention are shown.

[0017] Figure 2 The catalyst performance (a), methanol selectivity (c), and CO2 conversion rate (d) of the catalysts in Example 2 and Comparative Example 2 at 3 MPa, and the methanol selectivity and CO2 conversion rate (b) of the CZA-Ce-0.1NaBH4 / industrial methanol catalyst reaction for 504 h are shown. Detailed Implementation

[0018] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0019] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0020] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0021] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0022] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0023] Unless otherwise specified, "room temperature" or "room temperature" as used in this invention refers to 20-30℃.

[0024] The first aspect of this invention provides a method for preparing a catalyst, comprising the following steps:

[0025] The copper-zinc-aluminum catalyst was added to an aqueous solution of cerium nitrate, mixed thoroughly, and then stirred in a water bath to obtain a mixed solution.

[0026] An alkaline solution of NaBH4 is added to the mixed solution to react and a precipitate is obtained.

[0027] The precipitate was subjected to ultrasonic treatment, then washed, dried, ground, and calcined to obtain the catalyst.

[0028] The purpose of ultrasonic treatment of the precipitate is to make the reduction more complete.

[0029] In some embodiments of the present invention, the concentration of the cerium nitrate aqueous solution is 0.01–0.1 mol / L; the concentration of the copper-zinc-aluminum catalyst in the mixed solution is 60–150 mg / mL; the temperature of the water bath stirring is 303–363 K, and the time is 0.5–4 h. The mixing method is ultrasonic treatment for 0.5–2 h.

[0030] In some embodiments of the present invention, the concentration of NaBH4 in the alkaline solution of NaBH4 is 0 to 0.20 mol / L; the alkaline solution of NaBH4 also includes NaOH or KOH; the molar ratio of NaBH4 to NaOH or KOH is (1 to 3):1.

[0031] In some embodiments of the present invention, the volume ratio of the alkaline solution of NaBH4 to the mixed solution is (1-3):1; the reaction is specifically carried out at room temperature for 1-5 hours. The alkaline solution of NaBH4 is added dropwise.

[0032] In some embodiments of the present invention, the ultrasonic treatment time is 0.5 to 2 hours; the drying temperature is 323 to 353 K and the time is 8 to 15 hours; the washing is specifically performed using deionized water; and the calcination temperature is 583 to 633 K and the time is 3 to 6 hours.

[0033] In some embodiments of the present invention, the preparation method of the copper-zinc-aluminum catalyst includes the following steps:

[0034] Copper salt, zinc salt, and aluminum salt were dissolved in water according to the molar ratio Cu:Zn:Al = 2:1:1.2 to obtain solution A;

[0035] Dissolve the hydroxide and carbonate in water to obtain solution B;

[0036] Solution A and solution B were simultaneously added dropwise to water, stirred, and aged. The resulting solid was dried and then calcined to obtain the copper-zinc-aluminum catalyst.

[0037] The hydroxide is NaOH or KOH; the carbonate is Na2CO3 or K2CO3.

[0038] In some embodiments of the present invention, the copper salt is at least one of copper nitrate, copper sulfate, copper acetate, or copper chloride; the zinc salt is at least one of zinc nitrate, zinc chloride, zinc sulfate, or zinc acetate; the aluminum salt is at least one of aluminum nitrate, aluminum sulfate, aluminum chloride, or aluminum acetate; the concentration of zinc salt in solution A is 0.2–1.2 mol / L; the concentration of hydroxide in solution B is 1–2 mol / L; the molar ratio of hydroxide to carbonate is 2:1; the volume ratio of solution A to solution B is 1:(1–4); the aging temperature is 353 K for 10–15 h; the drying temperature is 343–363 K for 10–15 h; and the calcination temperature is 583–633 K for 3–6 h.

[0039] A second aspect of the present invention provides a catalyst prepared according to the preparation method described above.

[0040] A third aspect of the present invention provides the application of the above-described catalyst in the production of methanol by CO2 hydrogenation.

[0041] This invention focuses on CuZnAl non-noble metal catalysts. It improves the dispersion of Cu species and prevents their sintering and aggregation through a hydrotalcite-like structure with abundant pores, large specific surface area, and tunable framework metal ions and acid-base properties. Furthermore, it constructs Ce by introducing the promoter Ce into the catalyst and reducing it with sodium borohydride (NaBH4). 4+ / Ce 3+ and Cu 2+ / Cu δ+ / Cu 0 Redox electron pairs are used to establish electron transfer pathways and improve the catalytic performance of CO2 hydrogenation to methanol. Furthermore, the introduction of Ce can modulate the catalyst's acidity / basicity and provide abundant oxygen vacancies, which is beneficial for the efficient activation and hydrogenation conversion of CO2. Therefore, this invention uses NaBH4 reduction treatment to attempt to introduce more Ce into the catalyst. 4+ / Ce 3+ Redox electron pairs improve electron transfer efficiency within the catalyst, thereby further enhancing the catalytic performance of CO2 hydrogenation to methanol.

[0042] A fourth aspect of this invention provides a two-stage catalyst for the hydrogenation of CO2 to methanol, prepared from the above-described catalyst and a commercially available industrial methanol Cu / ZnO / Al2O3 catalyst. When used for the hydrogenation of CO2 to methanol, the catalyst (CZA-Ce-0.1NaBH4) is located near the inlet end, and the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst is located near the outlet end.

[0043] The fifth aspect of this invention provides the application of the above-described two-stage catalyst for CO2 hydrogenation to methanol in the CO2 hydrogenation to methanol process, comprising the following steps:

[0044] The catalyst (CZA-Ce-0.1NaBH4) and the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst were connected in series in a fixed-bed reactor tube at a volume ratio of 1:1, with the CZA-Ce-0.1NaBH4 catalyst located near the inlet and the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst located near the outlet. The reaction was carried out at 3 MPa for 6000 h⁻¹. -1 The process was carried out under the condition that CO2:H2 = 1:3.

[0045] Unless otherwise specified, all raw materials used in the embodiments of this invention can be obtained through commercial channels.

[0046] The present invention will be further illustrated by the following examples.

[0047] Example 1

[0048] Step 1, Preparation of copper-zinc-aluminum (CZA) catalyst

[0049] Copper-zinc-aluminum (CZA) catalyst was prepared by a co-current co-precipitation method, with the following steps: 14.50 g Cu(NO3)2·3H2O, 8.92 g Zn(NO3)3·6H2O, and 13.51 g Al(NO3)3·9H2O were added (maintaining the following molar ratio n...). Cu :n Zn :n Al The mixture of NaOH (2:1:1.2) and Na2CO3 (0.5 mol / L) was dissolved in 100 mL of deionized water to obtain solution A. 8 g of NaOH (1 mol / L) and 10.79 g of Na2CO3 (0.5 mol / L) were dissolved in 200 mL of deionized water, and this solution was denoted as solution B. Under conditions of 298 K and maintaining the pH of the mixed solution at 9-10 during titration, solutions A and B were simultaneously added dropwise to 100 mL of deionized water. After stirring for 1 hour, the resulting mixture was aged at 353 K for 12 hours and then cooled to room temperature. After filtration and washing until the pH reached 7, the resulting solid was dried in air at 353 K for 12 hours, followed by calcination at 623 K for 4 hours in air to obtain the CZA catalyst.

[0050] Step 2, impregnate Ce and treat with NaBH4

[0051] Dissolve 2.17 g of Ce(NO3)3·6H2O (0.05 mol / L) in 100 mL of deionized water, and then dissolve 13.5 g of the above CZA catalyst in the solution and sonicate for 30 min.

[0052] The mixture was transferred to a 353K water bath and stirred for 1 h. A freshly prepared mixed solution of NaBH4 (x mol / L) and NaOH (98% purity) was then pumped using a peristaltic pump at 353K with stirring (molar ratio n). NaBH4 :n NaOH =2:1) ​​100 mL was added dropwise to the solution after the water bath and reacted for 3 h. The resulting precipitate was sonicated for 30 min, washed with deionized water, and placed in a vacuum drying oven at 333 K overnight. After grinding, it was calcined at 623 K for 4 h under a nitrogen atmosphere to obtain the CZA-Ce-xNaBH4 catalyst (where x is the concentration of NaBH4 solution; when x = 0, the corresponding catalyst is labeled CZA-Ce; when x = 0.02, the corresponding catalyst is labeled CZA-Ce-0.02NaBH4; when x = 0.1, the corresponding catalyst is labeled CZA-Ce-0.1NaBH4; when x = 0.18, the corresponding catalyst is labeled CZA-Ce-0.18NaBH4).

[0053] Comparative Example 1

[0054] The only difference from Example 1 is that step 2 is omitted; all other steps and parameters are the same as in Example 1. The prepared catalyst is labeled CZA.

[0055] Example 2

[0056] The two-stage catalyst consisted of the CZA-Ce-0.1NaBH4 catalyst prepared in Example 1 at a volume ratio of 1:1 and a commercially available industrial methanol Cu / ZnO / Al2O3 catalyst from the prior art. It was named CZA-Ce-0.1NaBH4 / industrial catalyst.

[0057] The steps for applying this two-stage catalyst to the production of methanol via CO2 hydrogenation are as follows: The CZA-Ce-0.1NaBH4 catalyst prepared in Example 1 and a commercially available industrial methanol Cu / ZnO / Al2O3 catalyst from the prior art are loaded into the reaction tube using a two-stage loading method. The volume ratio of the two catalysts is 1:1, and the total volume is 1.5 mL. Specifically, 0.75 mL (approximately 0.351 g) of the CZA-Ce-0.1NaBH4 catalyst is placed near the inlet (upper), and 0.75 mL (approximately 0.452 g) of the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst is placed near the outlet (lower).

[0058] Comparative Example 2

[0059] The commercially available industrial methanol Cu / ZnO / Al2O3 catalyst from Example 2 was used as a catalyst for the hydrogenation of CO2 to methanol and was named the industrial catalyst.

[0060] Example 1: The catalysts prepared in Examples 1-2 and Comparative Examples 1-2 were applied to the CO2 hydrogenation to methanol production.

[0061] The catalytic performance evaluation of carbon dioxide hydrogenation was carried out in a fixed-bed reactor with an inner diameter of 12 mm. The catalyst (40–60 mesh, 1.5 mL) was packed in the middle of the reaction tube.

[0062] Before the reaction, the catalyst was reduced at 623 K and atmospheric pressure for 6 hours, with a gas flow rate of 80 mL / min and a V(H2):V(N2) ratio of 1:4. After cooling to room temperature, a feed gas with a volume ratio of H2 / CO2 of 3:1 was introduced into the reactor at 3.0 MPa or 4.0 MPa and 523 K, with a total flow rate of 120 mL / min. -1 In this process, the two catalyst stages do not involve pre-reduction; the reactant gas is directly introduced, pressurized to 3.0 or 4.0 MPa, and heated to 523 K.

[0063] The exhaust gas was analyzed using an online gas chromatograph GC-950N (Nanjing Gano Chromatography Technology Co., Ltd.). This instrument is equipped with a thermal conductivity detector (TCD) for detecting CO, CH4, and CO2, and a flame ionization detector (FID) for detecting C1-C5 hydrocarbons and alcohols. Data were collected while the reaction remained stable.

[0064] Carbon dioxide conversion rate (X) CO2 ) and product selectivity (S i Calculate according to the following formula:

[0065]

[0066] Where n i The molar number of carbon atoms in the product, n(CO2). in The value represents the number of moles of CO2 at the inlet, and g and l represent the gaseous and liquid phase products, respectively.

[0067] Discussion of Activity Evaluation Results

[0068] like Figure 1 As shown, compared with the CuZnAl catalyst without Ce (CZA), the Ce-modified CZA catalyst exhibits higher CO2 conversion and methanol selectivity. Notably, the catalytic performance of each catalyst is significantly improved at 4 MPa compared to 3 MPa. CZA-Ce-0.1NaBH4 demonstrates the best methanol selectivity at both 3 MPa and 4 MPa. Specifically, at 4 MPa, the CO2 conversion (Xco2) of CZA-Ce-0.1NaBH4 is 20.33%, and the methanol selectivity (Sco2) is [not specified in the original text]. CH3OHThe methanol selectivity was 51.70%. With increasing NaBH4 dosage, under 4 MPa conditions, the methanol selectivity first rose to 51.70% for CZA-Ce-0.1NaBH4, then decreased to 40.18% for CZA-Ce-0.18NaBH4, and the CO2 conversion rate showed a similar trend. The catalytic performance of the catalyst at 3 MPa followed the same pattern as at 4 MPa, indicating that moderate reduction treatment has a positive impact on the catalyst's performance. Furthermore, with increasing pressure, the effect of NaBH4 dosage on methanol selectivity was significantly greater than its effect on CO2 conversion rate (e.g., ...). Figure 1 As shown in (d) and (e)). Figure 1 As shown in (b)-(e), all catalysts exhibited relatively stable activity under both pressures, with no significant deactivation occurring within the studied reaction time. The addition of Ce not only improved catalytic performance but also significantly enhanced catalyst stability. CZA-Ce-0.1NaBH4 and CZA-Ce-0.02NaBH4 showed even better stability, indicating that the introduction of an appropriate amount of NaBH4 is beneficial for improving both catalyst activity and stability.

[0069] By reducing with NaBH4, Cu and Ce species of different valence states were introduced into the system in order to construct Cu... 2+ / Cu δ+ / Cu 0 and Ce 4+ / Ce 3+ The redox electron pair was used to promote the performance of CO2 hydrogenation to methanol. The effects of NaBH4 dosage on catalyst composition, structure, microstructure, acidity, and basicity were investigated. Key factors affecting methanol selectivity and CO2 conversion were explored, and the reaction mechanism was verified by in-situ infrared spectroscopy. The following conclusions were drawn:

[0070] (1) By adjusting the amount of NaBH4, the catalytic performance of CO2 hydrogenation to methanol on the catalyst was further improved, showing a trend of first rising and then falling. The CZA-Ce-0.1NaBH4 catalyst (4MPa) showed the best catalytic performance, with a CO2 conversion rate of 20.33% and a methanol selectivity of 51.70%.

[0071] (2) Key factors affecting CO2 conversion rate include strong basic sites in the catalyst and Ce. 3+ Content, Ce 3+ / Ce 4+ Ratio, oxygen vacancy content. Among them, Ce... 3+ The content of [acidic sites] shows a good linear relationship with CO2 conversion rate, making it the most significant influencing factor. Key factors affecting methanol selectivity include the content of weakly acidic sites in the catalyst and Cu [acidity]. δ+Content and Cu δ+ / (Cu 0 +Cu δ+ Linear fitting revealed that Cu δ+ / (Cu 0 +Cu δ+ ) compared to Cu δ+ The effect of content is more significant, further illustrating that interspecies interactions are a key factor influencing methanol selectivity. In summary, the improved overall performance of this series of catalysts may be attributed to the Ce-containing catalyst constructed by NaBH4 reduction. 4+ / Ce 3+ Cu δ+ / Cu 0 Electronic conduction and metal interaction system.

[0072] (3) According to the in-situ infrared characterization results, unlike common Ce-doped catalysts, the main reaction pathways of this series of catalysts are the simultaneous occurrence of the HCOO* pathway and the RWGS+CO pathway.

[0073] like Figure 2 As shown, compared to the single CZA-Ce-0.1NaBH4 catalyst, the catalytic performance of the tandem reaction changes significantly, with a substantial improvement in methanol selectivity. On the tandem catalyst CZA-Ce-0.1NaBH4 / industrial catalyst, the CO2 conversion rate is 9.28%, but the methanol selectivity reaches 85.5%. Comparing the activity data of the single CZA-Ce-0.1NaBH4 catalyst and the industrial methanol catalyst reveals that the tandem reaction combines the advantages of both catalysts, achieving a CO2 conversion rate intermediate between the two catalysts while maintaining higher selectivity, with CO being significantly suppressed.

[0074] Depend on Figure 2 As shown in Figures (b)-(d), the catalyst stability data demonstrate that all catalysts exhibit excellent stability within the evaluation time, with the CZA-Ce-0.1NaBH4 / industrial catalyst showing even better stability. Figure 2 In (b) of the reaction, no significant inactivation was observed within 504 hours. CO2 =9.28%, S CH3OH =85.5%.

[0075] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An application of a two-stage catalyst for the catalytic hydrogenation of CO2 to methanol, characterized in that, The two catalysts were prepared from CZA-Ce-NaBH4 catalyst and commercially available industrial methanol Cu / ZnO / Al2O3 catalyst. The CZA-Ce-NaBH4 catalyst and the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst were connected in series in a fixed-bed reactor tube at a volume ratio of 1:1, with the CZA-Ce-NaBH4 catalyst located near the inlet and the commercially available industrial methanol Cu / ZnO / Al2O3 catalyst located near the outlet. The reaction was carried out at 3 MPa for 6000 h⁻¹. -1 The process was carried out under conditions where CO2:H2 = 1:3; The preparation method of the CZA-Ce-NaBH4 catalyst includes the following steps: The copper-zinc-aluminum catalyst was added to an aqueous solution of cerium nitrate, mixed thoroughly, and then stirred in a water bath to obtain a mixed solution. An alkaline solution of NaBH4 is added to the mixed solution to react and a precipitate is obtained. The precipitate was subjected to ultrasonic treatment, then washed, dried, ground and calcined to obtain the CZA-Ce-NaBH4 catalyst. The concentration of NaBH4 in the alkaline solution is 0~0.20 mol / L, and is not 0 mol / L; the alkaline solution of NaBH4 also includes NaOH or KOH; the molar ratio of NaBH4 to NaOH or KOH is (1~3):

1.

2. The application according to claim 1, characterized in that, The concentration of the cerium nitrate aqueous solution is 0.01~0.1mol / L; the concentration of the copper-zinc-aluminum catalyst in the mixed solution is 60~150 mg / mL; the temperature of the water bath stirring is 303~363 K, and the time is 0.5~4 h.

3. The application according to claim 1, characterized in that, The volume ratio of the alkaline solution of NaBH4 to the mixed solution is (1~3):1; the reaction is specifically carried out at room temperature for 1~5 h.

4. The application according to claim 1, characterized in that, The ultrasonic treatment lasts for 0.5 to 2 hours; the drying temperature is 323 to 353 K and the drying time is 8 to 15 hours; the calcination temperature is 583 to 633 K and the calcination time is 3 to 6 hours.

5. The application according to claim 1, characterized in that, The preparation method of the copper-zinc-aluminum catalyst includes the following steps: Copper salt, zinc salt, and aluminum salt were dissolved in water according to the molar ratio Cu:Zn:Al = 2:1:1.2 to obtain solution A; Dissolve the hydroxide and carbonate in water to obtain solution B; Solution A and solution B were simultaneously added dropwise to water, stirred, and aged. The resulting solid was dried and then calcined to obtain the copper-zinc-aluminum catalyst. The hydroxide is NaOH or KOH; the carbonate is Na2CO3 or K2CO3.

6. The application according to claim 5, characterized in that, The copper salt is at least one of copper nitrate, copper sulfate, copper acetate, or copper chloride; the zinc salt is at least one of zinc nitrate, zinc chloride, zinc sulfate, or zinc acetate; the aluminum salt is at least one of aluminum nitrate, aluminum sulfate, aluminum chloride, or aluminum acetate; the concentration of zinc salt in solution A is 0.2~1.2 mol / L; the concentration of hydroxide in solution B is 1~2 mol / L; the molar ratio of hydroxide to carbonate is 2:1; the volume ratio of solution A to solution B is 1:(1~4); the aging temperature is 353 K, and the time is 10~15 h; the drying temperature is 343~363 K, and the time is 10~15 h; the calcination temperature is 583~633 K, and the time is 3~6 h.

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