CuZnHo catalyst for preparing methanol through catalytic hydrogenation of CO2 as well as preparation method and application of CuZnHo catalyst

Abstract

The invention relates to a CuZnHo catalyst for preparing methanol through catalytic hydrogenation of CO2 as well as a preparation method and application of the CuZnHo catalyst. The catalyst comprises Cu, Zn and Ho in a molar ratio of (5-6): (3-4.9): (0.1-2). Compared with the prior art, the heavy rare earth element holmium is innovatively introduced into the traditional CuO-ZnO catalyst, so that the novel CuZnHo catalyst can react CO2 with hydrogen at a lower temperature to generate methanol, the conversion rate of the carbon dioxide and the selectivity of the methanol are higher, and the space time yield of the methanol is higher. The CuZnHo catalyst is prepared by adopting a simple and efficient coprecipitation method, and the industrial application prospect is wide.

Description

Technical Field

[0001] The invention belongs to the field of carbon dioxide utilization, and in particular relates to a CuZnHo catalyst for preparing methanol by catalytic hydrogenation of CO2, and a preparation method and application thereof. Background Art

[0002] Greenhouse gas emissions, mainly carbon dioxide, will directly or indirectly lead to global warming, sea level rise, and affect global precipitation. Carbon dioxide has already posed a serious threat to the global climate and ecology. Carbon capture, utilization and storage (CCUS) is an important technical path, among which the chemical utilization of carbon dioxide refers to capturing and aggregating carbon dioxide in the atmosphere and then utilizing it through chemical means to turn waste into treasure. It is a hot topic with significant social and economic benefits.

[0003] Methanol has high energy storage density, high safety and low cost, and is a promising future energy storage carrier; it can also be used as a clean fuel for ships. The production of methanol by thermal catalytic hydrogenation of carbon dioxide has high economic benefits and high carbon dioxide conversion rate, and is industrially feasible. The current mainstream method is the one-step direct production of methanol, that is, direct reaction of CO2 and H2 to produce methanol. Compared with the two-step RWGS-Fischer-Tropsch synthesis method, it has fewer reaction steps, lower difficulty and higher energy efficiency.

[0004] At present, the commonly used catalysts for the hydrogenation of carbon dioxide to methanol reaction include transition metal oxide catalysts, molecular sieve catalysts, precious metal catalysts, MOF catalysts, etc. In general, the technology is still not fully mature, the carbon dioxide conversion rate is relatively low, and it is often difficult to have both high carbon dioxide conversion rate and high methanol selectivity. my country is at the forefront of the world in the development of catalysts for the hydrogenation of carbon dioxide to methanol. In 2017, the team of Academician Li Can developed a new zinc-zirconium solid solution catalyst (ZnO-ZrO2) and proposed the concept of "liquid sunshine", which has been demonstrated industrially in Lanzhou. After the catalyst participates in the reaction, the methanol selectivity is high and the catalyst stability is high, but the carbon dioxide conversion rate is low and the reaction conditions require high requirements (Sci. Adv., 2017, 3: e1701290). For traditional CuO-ZnO catalysts, their reaction activity is high, but the low methanol selectivity and poor stability often become important factors restricting their industrial application. Liu Jian et al. (Nat. Commun., 2024, 15: 2159) used the Ce-MOF precursor method to prepare a new Ce-CuZn catalyst. The methanol selectivity was improved compared with the ordinary copper-zinc catalyst, but it also led to a decrease in the carbon dioxide conversion rate; the new CuZnGa catalyst reported in the literature (ACS Catal., 2018, 8: 4390-4401) had a major breakthrough in carbon dioxide conversion rate and methanol production, but it also failed to solve the problem of low methanol selectivity.

[0005] In summary, the development of catalysts for the hydrogenation of carbon dioxide to methanol is still in the critical stage. Although researchers have made breakthroughs, the core problem has not been solved: high carbon dioxide conversion rate and high methanol selectivity are often not achieved at the same time. This has slowed the progress of industrial applications of carbon dioxide hydrogenation to methanol. Since the reaction of carbon dioxide hydrogenation to methanol may also generate by-products such as CO and CH4, how to prepare catalysts with high activity, high methanol selectivity and high stability has become a research focus. Among them, methanol selectivity is more important because it involves the cost of separation and purification of the subsequent main methanol product. Relatively speaking, the single-pass conversion rate of carbon dioxide can be compensated by cyclic reactions. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a CuZnHo catalyst for catalytic hydrogenation of CO2 to methanol and its preparation method and application, which has high carbon dioxide conversion rate, high methanol selectivity and high stability.

[0007] The object of the present invention can be achieved by the following technical scheme: a CuZnHo catalyst for catalytic hydrogenation of CO2 to produce methanol, the catalyst comprising Cu, Zn and Ho in a molar ratio of (5-6):(3-4.9):(0.1-2).

[0008] Furthermore, the molar ratio of Cu, Zn and Ho in the catalyst is 5:3:2.

[0009] The present invention also provides a method for preparing a CuZnHo catalyst for catalytic hydrogenation of CO2 to produce methanol, comprising the following steps: dissolving soluble copper salt, zinc salt and holmium salt in deionized water, then gradually adding a sodium carbonate aqueous solution, after a hydrothermal reaction, filtering, washing to neutrality, drying, and calcining in an air atmosphere to obtain the catalyst.

[0010] Furthermore, the copper salt includes copper nitrate, copper sulfate, copper chloride, copper acetate, etc.;

[0011] Zinc salts include zinc nitrate, zinc sulfate, zinc chloride, zinc acetate, etc.;

[0012] Holmium salts include holmium nitrate, holmium sulfate, holmium chloride, holmium acetate, and the like.

[0013] Furthermore, the hydrothermal reaction temperature is 70-90°C and the reaction time is 0.5-2h.

[0014] Furthermore, the drying temperature is 60-110° C. and the drying time is 8-20 hours.

[0015] Furthermore, the calcination temperature is 400-500° C. and the calcination time is 1-4 hours.

[0016] The present invention also provides an application of a CuZnHo catalyst, wherein the catalyst is used for catalytic hydrogenation of CO2 to produce methanol.

[0017] Furthermore, the reaction conditions for the catalytic hydrogenation of CO2 to produce methanol are: CO2:H2=1:(2-4), reaction pressure 3-4.5MPa, reaction temperature 180-300°C, reaction space velocity 6000-48000mL·g -1 ·h -1 .

[0018] Furthermore, before the reaction, the catalyst is in situ reduced at 300° C. in a 5% to 10% hydrogen atmosphere for 1 to 2 hours.

[0019] The present invention adopts coprecipitation to prepare CuZnHo catalyst, Cu 2+ 、Zn 2+ 、Ho 3+ The precipitation pH in aqueous solution is similar, so the co-precipitation method can be used to prepare the CuZnHo catalyst. The co-precipitation method is simple to operate, has few steps, and is highly repeatable. The active components in the prepared CuZnHo catalyst are evenly distributed. When using a soluble metal salt precursor, a large amount of deionized water will be used for washing in the suction filtration and washing step after the hydrothermal process is completed, and negative ions such as nitrate ions and sulfate ions can be well removed. 2+ Will be with NH4 + Therefore, sodium carbonate solution is selected as the alkali solution, which can completely precipitate the metal ions and the excess Na + It can be washed with a large amount of deionized water to be removed better. During the preparation process, the soluble metal salt will form an alkaline hydroxide in the hot alkali solution, and after high-temperature roasting, it will form a CuZnHo catalyst. The catalyst prepared by this method has strong interaction between the components, uniform dispersion, and high stability.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] One of the significant advantages of the catalyst of the present invention is that after the heavy rare earth element Ho is introduced, the catalyst's adsorption and activation ability for carbon dioxide and hydrogen is greatly improved, and the hydrogenation rate of carbon dioxide is extremely fast, so that the carbon dioxide conversion rate of the catalyst is greatly improved compared with the ordinary CuO-ZnO catalyst, while maintaining the methanol selectivity. Compared with the main commercial catalyst CuZnAl catalyst, the catalyst of the present invention has significantly higher methanol selectivity, and has the characteristics of both high methanol selectivity and high methanol yield.

[0022] The second significant advantage of the catalyst of the present invention is that the CuZnHo catalyst is prepared by a coprecipitation method, which can significantly improve the activity and methanol selectivity of the catalyst, and is simple to operate and has good industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Comparison of carbon dioxide conversion rates among CuZnHo (5:3:2) catalyst, CuZn (5:5) catalyst and CuHo (5:5) catalyst;

[0024] Figure 2 Comparison of methanol selectivity among CuZnHo (5:3:2) catalyst, CuZn (5:5) catalyst and CuHo (5:5) catalyst;

[0025] Figure 3 The effect of the content of each catalyst component on the catalytic activity of CuZnHo catalyst;

[0026] Figure 4 100-hour stability of CuZnHo (5:3:2) catalyst;

[0027] Figure 5 Comparison between CuZnHo (5:3:2) catalyst and CuZnAl (5:3:2) catalyst at the same reaction temperature;

[0028] Figure 6 To investigate the effect of preparation method on the catalytic activity of CuZnHo (5:3:2) catalyst;

[0029] Figure 7 The effect of reaction pressure on the catalytic activity of CuZnHo (5:3:2) catalyst;

[0030] Figure 8 The effect of reaction space velocity on the catalytic activity of CuZnHo (5:3:2) catalyst;

[0031] Fig. 9 The effect of calcination temperature on the catalytic activity of CuZnHo (5:3:2) catalyst;

[0032] Fig.10 This is the field emission transmission electron microscopy image of the CuZnHo (5:3:2) catalyst. DETAILED DESCRIPTION

[0033] The present invention will be described in detail below with reference to specific embodiments, but this does not limit the protection scope of the present invention.

[0034] Example 1

[0035] Preparation of CuZnHo (5:3:2) catalyst: 2.369 g of Cu(NO3)2·3H2O, 1.751 g of Zn(NO3)2·6H2O and 1.73 g of Ho(NO3)3·5H2O were dissolved in 100 mL of deionized water and stirred evenly to obtain a metal precursor solution; 2.286 g of anhydrous sodium carbonate was dissolved in 100 mL of deionized water to obtain an alkali solution. Under stirring in a water bath at 80°C, the alkali solution was slowly added dropwise to the metal precursor solution (3 mL / min), and then kept under stirring in a water bath at 80°C for one hour. After aging and cooling, the obtained precipitate was filtered and washed with a large amount of deionized water (>3L), then transferred to an 80°C oven overnight, and then placed in a muffle furnace and calcined at 400°C in an air atmosphere for 2 hours to obtain a CuZnHo (5:3:2) catalyst.

[0036] Example 2

[0037] The amount of raw materials was changed to make the molar ratio of Cu, Zn and Ho to be 5:4:1. The rest was the same as in Example 1.

[0038] Example 3

[0039] The amount of raw materials was changed to make the molar ratio of Cu, Zn and Ho to be 6:3:1. The rest was the same as in Example 1.

[0040] Example 4

[0041] The amount of raw materials was changed to make the molar ratio of CuZnHo to be 5:4.9:0.1, and the rest was the same as in Example 1.

[0042] Comparative Example 1

[0043] Preparation of CuZn (5:5) catalyst: 3.003 g of Cu (NO3) 2·3H2O and 3.695 g of Zn (NO3) 2·6H2O were dissolved in 100 mL of deionized water and stirred evenly; 2.639 g of anhydrous sodium carbonate was dissolved in 100 mL of deionized water to prepare alkali solution. Under stirring in a water bath at 80 ° C, the alkali solution was slowly added dropwise to the metal precursor solution (3 mL / min), and then kept under stirring in a water bath at 80 ° C for one hour. After aging and cooling, the obtained precipitate was filtered and washed with a large amount of deionized water (> 3L), then transferred to an 80 ° C oven overnight, and then placed in a muffle furnace and calcined at 400 ° C in an air atmosphere for 2 hours to obtain a CuZn (5:5) catalyst.

[0044] Comparative Example 2

[0045] Preparation of CuHo (5:5) catalyst: 1.801 g of Cu(NO3)2·3H2O and 3.284 g of Ho(NO3)3·5H2O were dissolved in 100 mL of deionized water and stirred evenly; 1.971 g of anhydrous sodium carbonate was dissolved in 100 mL of deionized water to prepare lye. Under stirring in a water bath at 80°C, the lye was slowly added dropwise to the metal precursor solution (3 mL / min), and then kept under stirring in a water bath at 80°C for one hour. After aging and cooling, the obtained precipitate was filtered and washed with a large amount of deionized water (>3L), then transferred to an 80°C oven overnight, and then placed in a muffle furnace and calcined at 400°C in an air atmosphere for 2 hours to obtain a CuHo (5:5) catalyst.

[0046] Comparative Example 3

[0047] Preparation of CuZnAl (5:3:2) catalyst: 3.246 g of Cu(NO3)2·3H2O, 2.398 g of Zn(NO3)2·6H2O and 2.016 g of Al(NO3)3·9H2O were dissolved in 100 mL of deionized water and stirred evenly; 3.133 g of anhydrous sodium carbonate was dissolved in 100 mL of deionized water to prepare alkali solution. Under stirring in a water bath at 80°C, the alkali solution was slowly added dropwise to the metal precursor solution (3 mL / min), and then kept under stirring in a water bath at 80°C for one hour. After aging and cooling, the obtained precipitate was filtered and washed with a large amount of deionized water (>3L), then transferred to an 80°C oven overnight, and then placed in a muffle furnace and calcined at 400°C in an air atmosphere for 2 hours to obtain a CuZnAl (5:3:2) catalyst.

[0048] Comparative Example 4

[0049] Preparation of Zn / CuHo catalyst: 2.369 g of Cu(NO3)2·3H2O and 1.73 g of Ho(NO3)3·5H2O were dissolved in 100 mL of deionized water and stirred evenly; 1.663 g of anhydrous sodium carbonate was dissolved in 70 mL of deionized water to prepare lye. Under stirring in a water bath at 80°C, the lye was slowly added dropwise to the metal precursor solution (3 mL / min), and then kept under stirring in a water bath at 80°C for one hour. After aging and cooling, the obtained precipitate was filtered and washed with a large amount of deionized water (>3 L), then transferred to an 80°C oven overnight, and then placed in a muffle furnace and calcined at 400°C in an air atmosphere for 2 hours.

[0050] The obtained solid was placed in 15 mL of deionized water, and 1.751 g of Zn(NO3)2·6H2O was added, stirred for 8 hours, dried by rotary evaporation, and calcined at 400°C in an air atmosphere for 2 hours to obtain the final Zn / CuHo catalyst.

[0051] Comparative Example 5

[0052] The preparation method of Ho / CuZn catalyst is the same as that of Comparative Example 4, except that CuZn is first co-precipitated and then Ho is impregnated.

[0053] Performance testing:

[0054] The performance of the catalysts obtained in the above examples and comparative examples was evaluated as follows:

[0055] The evaluation conditions of catalytic performance (carbon dioxide conversion rate, methanol selectivity, methanol space-time yield) are as follows: 0.1 g of catalyst and 0.4 g of quartz sand are fully mixed and placed in a stainless steel fixed bed reactor, and reacted in an atmosphere of CO2:H2:N2=23:69:8, reaction temperature 180-300°C, pressure 4.5 MPa, space velocity 6000 mL·g -1 ·h -1 Before the reaction gas was introduced, the catalyst was in situ reduced for 2 hours at 300°C in a 10% hydrogen atmosphere. The reaction tail gas was detected by a gas chromatograph.

[0056] Catalyst stability evaluation: 0.1 g of catalyst and 0.4 g of quartz sand were mixed evenly and placed in a stainless steel fixed bed reactor. Carbon dioxide hydrogenation to methanol reaction was carried out for 100 hours in an atmosphere of CO2:H2:N2=23:69:8 to examine the stability of the catalyst. The reaction temperature was 240°C, the pressure was 4.5 MPa, and the space velocity was 6000 mL·g -1 ·h -1 Before the reaction gas was introduced, the catalyst was reduced in situ at 300°C in a 10% hydrogen atmosphere for 2 hours.

[0057] The properties of the catalysts obtained in the examples and comparative examples are shown in Table 1 below (240° C.):

[0058]

[0059] (1) Carbon dioxide conversion rate

[0060] Figure 1 The figure is a comparison of the carbon dioxide conversion rate of the CuZnHo (5:3:2) catalyst prepared in Example 1, the CuZn (5:5) catalyst prepared in Comparative Example 1, and the CuHo (5:5) catalyst prepared in Comparative Example 2. Figure 1 It can be seen that the carbon dioxide conversion rate of the CuZnHo (5:3:2) catalyst is more than doubled compared with the CuZn (5:5) catalyst and the CuHo (5:5) catalyst.

[0061] (2) Methanol selectivity

[0062] The catalytic performance evaluation conditions are the same as above, that is, the methanol selectivity is simultaneously detected during the above catalyst performance evaluation process. Figure 2 The methanol selectivity comparison diagram of the CuZnHo (5:3:2) catalyst prepared in Example 1, the CuZn (5:5) catalyst prepared in Comparative Example 1, and the CuHo (5:5) catalyst prepared in Comparative Example 2 is shown in Table 1. Figure 2 It can be seen that the methanol selectivity of the three catalysts is very close, that is, the CuZnHo (5:3:2) catalyst still maintains good methanol selectivity under the premise of greatly improving the carbon dioxide conversion rate.

[0063] (3) Effect of the content of each catalyst component on the catalytic activity of the catalyst

[0064] like Figure 3 The following table shows the effect of different catalyst component dosages on catalytic activity in Examples 1-4. Figure 3 It can be seen that the order of the catalyst methanol space-time yield from large to small is CuZnHo (5:3:2) > CuZnHo (5:4:1) > CuZnHo (5:4.9:0.1) > CuZnHo (6:3:1), and the carbon dioxide conversion rate and methanol space-time yield of the CuZnHo (5:3:2) catalyst are significantly higher than those of CuZnHo (6:3:1), CuZnHo (5:4.9:0.1) and Comparative Example 3, i.e., CuZnAl (5:3:2), and the methanol selectivity is significantly higher than that of CuZnHo (5:4:1). The carbon dioxide conversion rate and methanol selectivity of CuZnHo (5:4:1), as well as the methanol selectivity of CuZnHo (5:4.9:0.1) and CuZnHo (6:3:1) are significantly higher than those of CuZnAl (5:3:2). Therefore, Cu:Zn:Ho=5:3:2 is the optimal ratio of the CuZnHo catalyst, and all examples are better than Comparative Example 3.

[0065] (4) Catalyst stability

[0066] Figure 4 The stability diagram of the catalyst performance obtained in Example 1 is shown in Table 1 and Figure 4 It can be seen that the carbon dioxide conversion rate and methanol selectivity of the CuZnHo (5:3:2) catalyst in the reaction remain stable within 100 hours.

[0067] (5) Carbon dioxide conversion, methanol selectivity and methanol space-time yield of each catalyst at the same reaction temperature

[0068] The catalytic performance evaluation conditions are the same as above, except that the reaction temperature is 240°C. Figure 5The figure shows a comparison of the methanol selectivity and methanol space-time yield of the CuZnHo (5:3:2) catalyst prepared in Example 1, the CuZn (5:5) catalyst prepared in Comparative Example 1, the CuHo (5:5) catalyst prepared in Comparative Example 2, and the CuZnAl (5:3:2) catalyst prepared in Comparative Example 3. It can be seen from the figure that the CuZnHo (5:3:2) catalyst has obvious advantages: at the same temperature, the CuZnHo (5:3:2) catalyst exhibits much higher carbon dioxide conversion rate and methanol space-time yield than the CuZn (5:5) catalyst and the CuHo (5:5) catalyst; and higher carbon dioxide conversion rate, methanol selectivity and methanol space-time yield than the CuZnAl (5:3:2) catalyst.

[0069] (6) Effect of different preparation conditions

[0070] Figure 6 The graph is a comparison of carbon dioxide conversion and methanol selectivity of the CuZnHo (5:3:2) catalyst prepared in Example 1, the Zn / CuHo catalyst prepared in Comparative Example 4, and the Ho / CuZn catalyst prepared in Comparative Example 5. Figure 6 It can be seen that the co-precipitation method has great advantages over other methods and has good methanol selectivity while ensuring high activity.

[0071] (7) Effect of reaction pressure on catalyst performance

[0072] The reaction pressure in the catalytic performance evaluation conditions was adjusted from 4.5 MPa to 3 MPa, and the performance of the catalyst obtained in Example 1 was tested:

[0073] like Figure 7 As shown, it can be seen that increasing the pressure of the reaction system can significantly improve the methanol selectivity of the CuZnHo (5:3:2) catalyst.

[0074] (8) Effect of reaction space velocity on catalyst performance

[0075] Figure 8 The activity of the catalyst obtained in Example 1 at different space velocities was shown by changing the reaction gas space velocity to 6000 mL·g -1 ·h -1 、12000mL·g -1 ·h -1 、18000mL·g -1 ·h -1 、24000mL·g -1 ·h -1 、30000mL·g -1 ·h -1 、36000mL·g -1 ·h -1、42000mL·g -1 ·h -1 、48000mL·g -1 ·h -1 As can be seen from the figure, with the increase of space velocity, the carbon dioxide conversion rate decreases slightly, while the methanol selectivity and methanol space-time yield gradually increase.

[0076] (9) Effect of different calcination temperatures on catalyst performance

[0077] The calcination temperature in Example 1 was adjusted from 400°C to 500°C, and the rest was the same as in Example 1. The activities of the catalysts prepared at different calcination temperatures were observed. Fig. 9 As shown, it can be seen that with the increase of calcination temperature, the selectivity of methanol remains almost unchanged, but the conversion rate of carbon dioxide decreases significantly, and the activity of the catalyst calcined at 400°C is significantly better than that of the catalyst calcined at 500°C.

[0078] (10) Field emission transmission electron microscopy image of CuZnHo (5:3:2) catalyst

[0079] Fig.10 This is a picture of the catalyst obtained in Example 1 under a field emission transmission electron microscope. Fig.10 (a-d) It can be seen that the catalyst obtained in Example 1 is amorphous; Fig.10 The high-angle annular dark field images (e-i) show that the metal elements are evenly distributed in the CuZnHo (5:3:2) catalyst obtained in Example 1, proving that the preparation method of the present invention successfully produces a CuZnHo catalyst with evenly distributed active components.

Claims

1. A method for CO 2 CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The catalyst comprises Cu, Zn and Ho in a molar ratio of (5-6):(3-4.9):(0.1-2).

2. A method for CO according to claim 1 2 CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The molar ratio of Cu, Zn and Ho in the catalyst is 5:3:

2.

3. A method for CO as claimed in claim 1 or 2 2 Preparation method of CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The following steps are involved: Soluble copper salt, zinc salt and holmium salt are dissolved in deionized water, and then sodium carbonate aqueous solution is gradually added dropwise. After hydrothermal reaction, the mixture is filtered, washed to neutrality, dried, and calcined in air atmosphere to obtain a catalyst.

4. The method for use in CO according to claim 3 2 Preparation method of CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The copper salts include copper nitrate, copper sulfate, copper chloride, copper acetate, etc. Zinc salts include zinc nitrate, zinc sulfate, zinc chloride, zinc acetate, etc.; Holmium salts include holmium nitrate, holmium sulfate, holmium chloride, holmium acetate, and the like.

5. The method for use in CO according to claim 3 2 Preparation method of CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The hydrothermal reaction temperature is 70-90°C and the reaction time is 0.5-2h.

6. The method for use in CO according to claim 3 2 Preparation method of CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The drying temperature is 60-110° C. and the drying time is 8-20 hours.

7. The method for use in CO according to claim 3. 2 Preparation method of CuZnHo catalyst for catalytic hydrogenation to methanol, It is characterized in that The calcination temperature is 400-500°C and the calcination time is 1-4h.

8. Use of the CuZnHo catalyst as claimed in claim 1 or 2, It is characterized in that The catalyst was used for CO 2 Catalytic hydrogenation to methanol.

9. Use of the CuZnHo catalyst according to claim 8, It is characterized in that CO 2 The reaction conditions for catalytic hydrogenation to produce methanol are: CO 2 :H 2 =1:(2-4), reaction pressure 3-4.5MPa, reaction temperature 180-300℃, reaction space velocity 6000-48000mL·g -1 ·h -1 .

10. Use of the CuZnHo catalyst according to claim 8, It is characterized in that Before the reaction, the catalyst is in situ reduced at 300° C. in a 5% to 10% hydrogen atmosphere for 1 to 2 hours.

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