Catalyst For Preparing a-Phenylethanol By Hydrogenation Of Acetophenone, Preparation Method Thereof And Application Thereof

Abstract

Disclosed is a preparation method of a catalyst for liquid phase hydrogenation of acetophenone in preparation of -phenylethanol, including: adding water, a small alcohol, a Gemini surfactant and an organic pore-forming agent to a reactor, followed by adding a silica sol and stirring well to prepare an aqueous dispersion of silica sol; preparing an alkaline precipitant and a mixed solution containing salts of a copper containing compound, a zinc containing compound, a rare-earth metal containing compound and an alkaline-earth metal containing compound, adding the alkaline precipitant and the mixed solution together to the aqueous dispersion of silica sol, followed by precipitation, ageing, filtration, washing, drying, calcination and molding to obtain the catalyst. By using silica sol and silicate as a composite silicon source, adding an organic pore-forming agent before the precipitation process, and modifying the catalyst by Zn, rare-earth metal and alkaline earth metal, when using in the liquid phase hydrogenation of acetophenone to prepare -phenylethanol, the catalyst of the present invention not only has high activity and good selectivity, but also effectively improves the liquid resistance of the catalyst, the catalyst also has high strength and good stability.

Claims

1. A preparation method for a hydrogenation catalyst, comprising the following steps: (1) adding water, a small molecule alcohol, a Gemini surfactant and an organic pore-forming agent to a reactor, followed by adding a silica sol and stirring the mixture well to prepare an aqueous dispersion of silica sol containing the small molecule alcohol, the Gemini surfactant and the organic pore-forming agent; (2) dissolving a salt of a copper containing compound, a salt of a zinc containing compound, a salt of a rare-earth metal containing compound and a salt of an alkaline-earth metal containing compound in water to prepare a solution of mixed salt; dissolving a silicon containing alkaline precipitant and a silicon free alkaline precipitant in water to prepare an aqueous solution of alkaline precipitant; adding the solution of mixed salt and the aqueous solution of alkaline precipitant together to the aqueous dispersion of silica sol for reaction, with the pH of the reaction system during the reaction process being controlled at 5.0-9.0, and followed by aging to obtain a slurry; (3) filtering and washing the slurry to obtain a filter cake; (4) drying, calcining and molding the filter cake to obtain the catalyst.

2. The preparation method according to claim 1, wherein the total amount of silicon in the catalyst is introduced together by the silica sol and the silicon containing alkaline precipitant, and the amount of silicon introduced by the silica sol accounts for 30-70 wt %, preferably 35-65 wt %, and more preferably 40-60 wt % of the total amount of silicon in the catalyst; preferably, the silica sol is an alkaline silica sol, with a pH value of 8.0-10.0.

3. The preparation method according to claim 1, wherein the silicon containing alkaline precipitant is a water soluble silicate, preferably selected from the group consisting of sodium silicate and potassium silicate and combinations thereof; the silicon free alkaline precipitant is selected from the group consisting of potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium hydroxide, potassium hydroxide, ammonium carbonate, ammonium bicarbonate, carbamide and ammonia water and combinations thereof.

4. The preparation method according to claim 1, wherein the particle size of the organic pore-forming agent is <100 mm, preferably 1-80 m, more preferably 3-30 m; preferably, the organic pore-forming agent is selected from the group consisting of PMMA, microcrystalline cellulose and methyl cellulose and combinations thereof.

5. The preparation method according to claim 1, wherein the amount of the organic pore-forming agent accounts for 0.5-20 wt %, preferably 1-10 wt %, more preferably 2-5 wt % of the total weight of the catalyst.

6. The preparation method according to claim 1, wherein in step (1), the mass ratio of the small molecule alcohol to water is 1:20 to 1:10; preferably, the small molecule alcohol in step (1) is selected from the group consisting of methanol, ethanol, propanol and butanol and combinations thereof.

7. The preparation method according to claim 1, wherein the Gemini surfactant in the step (1) is added in an amount of 0.1%-1% of the total mass of the water and the small molecular alcohol; preferably, the Gemini surfactant is a bromide having a structure of C.sub.m-n-m, wherein m is 12, 14, or 16, and n is 2, 3, 6, 8, or 10.

8. The preparation method according to claim 1, wherein the rare-earth metal is lanthanum and/or cerium; the alkaline-earth metal is selected from the group consisting of magnesium, calcium and barium and combinations thereof; preferably, the salt of the copper containing compound is selected from the group consisting of copper nitrate, copper chloride and copper acetate and combinations thereof; the salt of the zinc containing compound is selected from the group consisting of zinc nitrate, zinc chloride and zinc acetate and combinations thereof; the salt of the rare-earth metal compound is selected from the group consisting of nitrate, chloride and acetate and combinations thereof; the salt of alkaline-earth metal compound is selected from the group consisting of nitrate, chloride and acetate and combinations thereof.

9. The preparation method according to claim 1, wherein the temperature of the reaction process and the aging process in step (2) is 60-90 C.; in step (4), the calcining temperature is 300-700 C. and the calcining time is 4-12 h.

10. The catalyst prepared by the preparation method according to claim 1; preferably, based on the total weight of the catalyst, the prepared catalyst contains 20-65 wt % of copper oxide, 15-50 wt % of silicon oxide, 2-25 wt % of zinc oxide, 0.1-5 wt % of rare-earth metal oxide and 0.5-15 wt % of alkaline-earth metal oxide; more preferably, the prepared catalyst contains 40-63 wt % of copper oxide, 20-45 wt % of silicon oxide, 5-20 wt % of zinc oxide, 0.2-3 wt % of rare-earth metal oxide and 0.5-10 wt % of alkaline-earth metal oxide; still more preferably, the prepared catalyst contains 42-60 wt % of copper oxide, 22-40 wt % of silicon oxide, 10-18 wt % of zinc oxide, 0.5-2 wt % of rare-earth metal oxide and 1-5 wt % of alkaline-earth metal oxide.

11. A method for producing -phenylethanol in the liquid phase hydrogenation of acetophenone, comprising using the catalyst prepared by the preparation method according to claim 1.

12. The method according to claim 11, wherein before catalyzing the hydrogenation of acetophenone to produce -phenylethanol, the catalyst is reduced and activated; preferably, the reduction and activation of the catalyst includes the following steps: introducing a mixed gas of hydrogen and nitrogen with a volume fraction of H.sub.2 not more than 10 v % while maintaining the volume space velocity of the mixed gas of hydrogen and nitrogen to be 300-1000 h.sup.1 to pre-reduce the catalyst for at least 0.5 h, followed by gradually increasing the proportion of hydrogen in mixed gas of hydrogen and nitrogen and controlling the hot spot temperature of the catalyst bed in this process to not exceed 220 C., and finally raising the temperature to 200-220 C. and reducing in a pure hydrogen atmosphere for 2-5 h to obtain an activated catalyst; preferably, the process conditions for the hydrogenation of acetophenone to produce -phenylethanol using the obtained activated catalyst include: a reaction pressure of 2.5-5 MPa, a reaction temperature of 70-140 C., a H.sub.2/ACP molar ratio of 2-20:1 and a catalyst amount of 0.2-0.6 g.sub.ACP.Math.g.sub.cat.sup.1.Math.h.sup.1.

Description

EMBODIMENT

[0040] The method of the present invention is described in detail below with reference to the examples, but the present invention is not limited thereto.

[0041] The side pressure strength of the catalyst was measured using a particle strength tester, and the used catalyst was immersed and protected with ethylbenzene to prevent the catalyst from being oxidized. The side pressure strengths of 40 pellets of the reacted catalyst were measured and the average value was taken.

[0042] The copper ion content in the hydrogenation solution was measured by inductively coupled plasma-atomic emission spectrometry (ICP).

[0043] Unless otherwise specified, the reagents used below are analytically pure and are commercially available products.

Example 1

[0044] Into a reactor, 200 g of water, 10 g of methanol, 4.0 g of PMMA with a particle size of 10-30 m, and 2.0 g of Gemini surfactant with a structure of C.sub.16-6-16 (purchased from Henan Daochun Chemical Co., Ltd) were added and mixed evenly, and then 120.0 g of alkaline silica sol with a concentration of 30 wt % and a pH value of 9 was added and stirred well. 332.2 g of copper nitrate, 73.1 g of zinc nitrate, 21.3 g of lanthanum nitrate, 12.7 g of magnesium nitrate were dissolved in 1.5 kg of water to prepare an aqueous solution of mixed salt, 113.5 g of sodium silicate and 142.5 g of sodium carbonate were dissolved in water to prepare a precipitant solution, the two solutions were heated to 70 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 70 C., the pH of the system was controlled at 7.0 and the reaction time was 1 h. After the addition of the two solutions was completed, the pH of the system was adjusted to >7.5 using a solution with 10 wt % sodium carbonate, the system was aged at 75 C. for 3 h, then filtered, washed, the filter cake was dried at 110 C. for 12 h, calcined at 350 C. for 8 h, then mixed with 1.5 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 200 g of Catalyst A was obtained. Based on the oxides, the catalyst contains 55% of copper oxide, 30% of silicon oxide, 10% of zinc oxide, 1% of lanthanum oxide and 4% of magnesium oxide.

[0045] Catalyst reduction: the catalyst A was charged in a fixed-bed hydrogenation reactor, and the charging amount of the catalyst was 100 ml. The catalyst was reduced under a mixed gas of nitrogen and hydrogen before use. During the reduction, the volume space velocity of the mixed gas was maintained at 300 h.sup.1. The temperature of the reactor was first raised to 160 C. and the temperature was maintained for 2 h to remove the physical water adsorbed by the catalyst, and then a mixed gas of nitrogen and hydrogen with a H.sub.2 volume fraction of 5 v % was added to pre-reduce the catalyst for 1 h. Then the proportion of hydrogen in the mixed gas of nitrogen and hydrogen was gradually increased to 10 v %, 20 v %, 50 v % and 100 v %, the hot spot temperature of the catalyst bed in this process was controlled not to exceed 220 C., finally the temperature was raised to 220 C. and the catalyst was reduced under a pure hydrogen atmosphere for 3 h.

[0046] The hydrogenation raw material was an ethylbenzene solution with 15 wt % acetophenone, and the reaction was carried out under the conditions of a pressure of 2.5 Mpa, a temperature of 70 C., a molar ratio of H.sub.2/ketone of 5:1, and a catalyst throughput of 0.3 g.sub.HPA/g.sub.cat/h. The hydrogenation solution was taken every 24 h and the copper ion content in the hydrogenation solution was measured. After 100 hours of reaction, the catalyst was removed from the reactor and the catalyst was sieved with a stainless steel sample sieve with a diameter of 2 mm, and the ratio of the mass of the catalyst particles with a particle size of <1 mm to the total mass of the catalyst was calculated and used as the catalyst damage rate. A particle strength tester was used to determine the side pressure strength of the catalyst after the reaction. The results of the hydrogenation reaction and the average copper ion content in the hydrogenation solution are shown in Table 1. See Table 2 for comparison of the catalyst before and after the reaction.

Example 2

[0047] Into a reactor, 200 g of water, 15 g of ethanol, 6.0 g of microcrystalline cellulose with a particle size of 5-30 m, and 0.5 g of Gemini surfactant with a structure of C.sub.12-10-12 (purchased from Henan Daochun Chemical Co., Ltd.) were added, and then 61.3 g of silica sol with a concentration of 30 wt % was added and stirred well. 362.4 g of copper nitrate, 87.7 g of zinc nitrate, 22.7 g of cerium nitrate, 4.21 g of calcium nitrate were dissolved in 1.45 kg of water to prepare an aqueous solution of mixed salt, 130.5 g of sodium silicate and 149.0 g of sodium carbonate were dissolved in water to prepare a precipitant solution. The two solutions were heated to 75 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 75 C., the pH of the system was controlled at 7.2 and the reaction time was 1 h. After the addition of the two solutions was completed, the pH of the system was adjusted to >7.5 using a solution with 10 wt % sodium carbonate, the system was aged at 80 C. for 3 h, then filtered, washed, the filter cake was dried at 100 C. for 24 h, calcined at 400 C. for 12 h, then mixed with 1.0 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 200 g of Catalyst B was obtained. Based on the oxides, the catalyst contains 60% of copper oxide, 23% of silicon oxide, 12% of zinc oxide, 0.5% of cerium oxide and 4.5% of calcium oxide.

[0048] For the remaining conditions, refer to Example 1.

Example 3

[0049] Into a reactor, 200 g of water, 10 g of propanol, 10.0 g of methylcellulose with a particle size of 5-20 m, and 1.0 g of Gemini surfactant with a structure of C.sub.14-8-14 (purchased from Henan Daochun Chemical Co., Ltd.) were added and mixed evenly, and then 116.7 g of silica sol with a concentration of 30 wt % was added and stirred well. 302 g of copper nitrate, 87.7 g of zinc nitrate, 5.0 g of cerium nitrate, 6.8 g of barium nitrate were dissolved in 1.37 kg of water to prepare an aqueous solution of mixed salt, 198.7 g of sodium silicate and 93.6 g of sodium carbonate were dissolved in water to prepare a precipitant solution. The two solutions were heated to 80 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 80 C., the pH of the system was controlled at 8.0 and the reaction time was 1 h. After the addition of the two solutions was completed, the pH of the system was adjusted to >7.3 using a solution with 10 wt % sodium carbonate, the system was aged at 85 C. for 3 h, then filtered, washed, the filter cake was dried at 120 C. for 12 h, calcined at 550 C. for 8 h, then mixed with 1.2 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 200 g of Catalyst C was obtained. Based on the oxides, the catalyst contains 50% of copper oxide, 35% of silicon oxide, 12% of zinc oxide, 1% of cerium oxide and 2% of barium oxide.

[0050] For the remaining conditions, refer to Example 1.

Example 4

[0051] Into a reactor, 200 g of water, 20 g of butanol, 6.0 g of microcrystalline cellulose with a particle size of 3-20 m, and 0.2 g of Gemini surfactant with a structure of C.sub.12-8-12 (purchased from Henan Daochun Chemical Co., Ltd.) were added and mixed evenly, and then 105 g of silica sol with a concentration of 30 wt % was added and stirred well. 271.8 g of copper nitrate, 109.7 g of zinc nitrate, 10.6 g of lanthanum nitrate, 25.3 g of calcium nitrate were dissolved in 1.39 kg of water to prepare an aqueous solution of mixed salt, 182.1 g of sodium silicate and 105.6 g of sodium carbonate were dissolved in water to prepare a precipitant solution. The two solutions were heated to 60 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 60 C., the pH of the system was controlled at 6.5 and the reaction time was 1 h. After the addition of the two solutions was completed, the pH of the system was adjusted to >7.2 using a solution with 10 wt % sodium carbonate, the system was aged at 70 C. for 3 h, then filtered, washed, the filter cake was dried at 100 C. for 12 h, calcined at 450 C. for 6 h, then mixed with 1.0 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 200 g of Catalyst D was obtained. Based on the oxides, the catalyst contains 45% of copper oxide, 35% of silicon oxide, 15% of zinc oxide, 2% of lanthanum oxide and 3% of calcium oxide.

[0052] For the remaining conditions, refer to Example 1.

Example 5

[0053] Into a reactor, 200 g of water, 20 g of ethanol, 10.0 g of PMMA with a particle size of 10-30 m, and 1.5 g of Gemini surfactant with a structure of C.sub.14-10-14 (purchased from Henan Daochun Chemical Co., Ltd.) were added and mixed evenly, and then 177.3 g of silica sol with a concentration of 30 wt % was added and stirred well. 24.6 g of copper nitrate, 131.6 g of zinc nitrate, 7.97 g of lanthanum nitrate, 31.8 g of magnesium nitrate were dissolved in 1.65 kg of water to prepare an aqueous solution of mixed salt, 107.8 g of sodium silicate and 128.7 g of sodium carbonate were dissolved in water to prepare a precipitant solution. The two solutions were heated to 85 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 85 C., the pH of the system was controlled at 7.0 and the reaction time was 1 h. After the addition of the two solutions was completed, the pH of the system was adjusted to >7.5 using a solution with 10 wt % sodium carbonate, the system was aged at 90 C. for 3 h, then filtered, washed, the filter cake was dried at 110 C. for 12 h, calcined at 650 C. for 4 h, then mixed with 1.2 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 200 g of Catalyst E was obtained. Based on the oxides, the catalyst contains 40% of copper oxide, 38% of silicon oxide, 18% of zinc oxide, 1.5% of lanthanum oxide and 2.5% of calcium oxide.

[0054] For the remaining conditions, refer to Example 1.

Example 6

[0055] Into a reactor, 200 g of water, 15 g of methanol, 4.0 g of methylcellulose with a particle size of 3-30 m, and 0.8 g of Gemini surfactant with a structure of C.sub.12-8-12 (purchased from Henan Daochun Chemical Co., Ltd.) were added and mixed evenly, and then 117.3 g of silica sol with a concentration of 30 wt % was added and stirred well. 314.1 g of copper nitrate, 73.1 g of zinc nitrate, 5.0 g of cerium nitrate, 17.0 g of barium nitrate were dissolved in 1.5 kg of water to prepare an aqueous solution of mixed salt, 136.2 g of sodium silicate and 121.2 g of sodium carbonate were dissolved in water to prepare a precipitant solution. The two solutions were heated to 65 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 65 C., the pH of the system was controlled at 6.8 and the reaction time was 1 h. After the addition of the two solutions was completed, the pH of the system was adjusted to >7.5 using a solution with 10 wt % sodium carbonate, the system was aged at 70 C. for 3 h, then filtered, washed, the filter cake was dried at 110 C. for 24 h, calcined at 450 C. for 8 h, then mixed with 1.5 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 200 g of Catalyst F was obtained. Based on the oxides, the catalyst contains 52% of copper oxide, 32% of silicon oxide, 10% of zinc oxide, 1% of cerium oxide and 5% of barium oxide.

[0056] For the remaining conditions, refer to Example 1.

Examples 7-12

[0057] Example 7 is basically the same as Example 1, except that the Gemini surfactant used in Example 7 was a Gemini surfactant with a structure of C.sub.16-2-16, ethylenebis(hexadecyldimethylammonium bromide) (purchased from Henan Daochun Chemical Co., Ltd.).

[0058] Example 8 is basically the same as Example 2, except that the Gemini surfactant used in Example 8 was a Gemini surfactant with a structure of C.sub.12-3-12, propylenebis(dodecyldimethylammonium bromide) (purchased from Henan Daochun Chemical Co., Ltd.).

[0059] Example 9 is basically the same as Example 3, except that the Gemini surfactant used in Example 9 was a Gemini surfactant with a structure of C.sub.14-2-14, ethylenebis(tetradecyldimethylammonium bromide) (purchased from Henan Daochun Chemical Co., Ltd.).

[0060] Example 10 was basically the same as Example 4, except that the Gemini surfactant used in Example 10 was a Gemini surfactant with a structure of C.sub.12-3-12, propylenebis(dodecyldimethylammonium bromide) (purchased from Henan Daochun Chemical Co., Ltd.).

[0061] Example 11 is basically the same as Example 5, except that the Gemini surfactant used in Example 11 was a Gemini surfactant with a structure of C.sub.14-2-14, ethylenebis(tetradecyldimethylammonium bromide) (purchased from Henan Daochun Chemical Co., Ltd.).

[0062] Example 12 is basically the same as Example 6, except that the Gemini surfactant used in Example 12 was a Gemini surfactant with a structure of C.sub.12-3-12, propylenebis(dodecyldimethylammonium bromide) (purchased from Henan Daochun Chemical Co., Ltd.).

Comparative Example 1

[0063] 200 g of water was added to a reactor, and 60 g of fumed silica was added, and the mixture was stirred well. 332.2 g of copper nitrate was dissolved in 1.5 kg of water to prepare an aqueous solution of mixed salt, and an aqueous solution with 10 wt % sodium carbonate was prepared as a precipitant, and the two solutions were heated to 65 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 65 C., the pH of the system was controlled at 7.0 and the reaction time was 1 h. After the addition was completed, the system was aged at 70 C. for 3 h, then filtered, washed, the filter cake was dried at 110 C. for 24 h, calcined at 450 C. for 8 h, then mixed with 1.2 wt % (powder mass) of graphite and pressed into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 170 g of Catalyst G was obtained.

[0064] For the remaining conditions, refer to Example 1.

Comparative Example 2

[0065] 332.2 g of copper nitrate and 292.4 g of zinc nitrate were dissolved in 1.65 kg of water to prepare an aqueous solution of mixed salt, sodium carbonate was dissolved in water to prepare an aqueous solution with 10 wt % sodium carbonate, and the two solutions were heated to 65 C. respectively. The coprecipitation method was used, the two solutions were added dropwise into the reactor at the same time, and the temperature in the reactor during the precipitation process was controlled at 65 C., the pH for precipitation was controlled at 7.0. After the precipitation was completed, the system was aged at 70 C. for 3 h. After filtration and washing, 10.0 g of alumina was added to the filter cake, the treated filtered cake was dried at 110 C. for 12 h, calcined at 350 C. for 4 h, then mixed with 1.5 wt % (powder mass) of graphite, pressed and molded into a 33 mm cylinder (3 mm in diameter and 3 mm in height) catalyst, about 190 g of Catalyst H was obtained.

[0066] For the remaining conditions, refer to Example 1.

Comparative Example 3

[0067] During the preparation of the catalyst, no small molecular alcohol and Gemini surfactant were added, and the remaining conditions were the same as in Example 1. About 200 g of Catalyst I was obtained.

[0068] For the remaining conditions, refer to Example 1.

Comparative Example 4

[0069] During the preparation of the catalyst, no organic pore-forming agent PMMA was added, and the remaining conditions were the same as in Example 1. About 200 g of Catalyst J was obtained.

[0070] For the remaining conditions, refer to Example 1.

[0071] The results of the hydrogenation reaction of the catalysts of Examples 1-6 and the average copper ion contents in the hydrogenation solution are shown in Table 1, and the comparison of the catalysts before and after the reaction are shown in Table 2. The experimental results of the catalysts prepared in Examples 7-12 are basically the same as the corresponding experimental results of Examples 1-6 in sequence, in which the conversion rate of acetophenone were at least 98.1%, and the selectivity to -phenylethanol were all at least 99.3%, the detection results of the average copper ion content in the hydrogenation solution were not detected; the side pressure strength of the catalysts before the reaction were all at least 188 N/particle, and the side pressure strength of the catalysts after the reaction were all at least 48.5 N/particle. The catalysts after the reaction were all complete without powdering and crushing.

TABLE-US-00001 TABLE 1 The results of the hydrogenation reaction and average copper ion content in the hydrogenation solution average copper ion selectivity to content in the conversion rate of -phenylethanol hydrogenation acetophenone % % solution g/g Catalyst A 98.1 99.4 Not detected Catalyst B 99.3 99.3 Not detected Catalyst C 98.8 99.4 Not detected Catalyst D 98.9 99.5 Not detected Catalyst E 98.6 99.3 Not detected Catalyst F 99.2 99.5 Not detected Catalyst G 86.0 97.5 38.2 Catalyst H 82.1 97.6 60.8 Catalyst I 92.6 98.7 Not detected Catalyst J 93.1 98.5 Not detected Note: Not detected means the average copper ion content in the hydrogenation solution is <0.1 g/g

TABLE-US-00002 TABLE 2 Comparison of the catalyst before and after the reaction catalyst before catalyst after the reaction the reaction side pressure side pressure catalyst after strength N/particle* strength N/particle the reaction state Catalyst A 188.1 48.5 complete Catalyst B 210.9 65.9 complete Catalyst C 220.6 68.1 complete Catalyst D 192.3 54.4 complete Catalyst E 205.7 62.3 complete Catalyst F 198.3 58.9 complete Catalyst G 163.2 15.7 crushed Catalyst H 106.7 could not powdered be tested Catalyst I 195.7 55.3 complete Catalyst J 198.2 58.5 complete *N/particle is the unit of catalyst strength, which is the force applied for 1 catalyst to crush

[0072] As can be seen from Tables 1 and 2, when using catalysts A to F, and catalysts I and J, no copper was detected in the hydrogenation solution, and the catalysts were complete and the side pressure strength of the catalysts were at least 30 N/particle after the reaction; however, as to the catalysts of Comparative Example 1 and Comparative Example 2, after the reaction, the catalysts were severely crushed and the side pressure strength of the catalysts were low. The catalyst H was powdered so that its side pressure strength could not be tested. ICP analysis showed that the copper content in the hydrogenation solution of the catalysts were high, indicating that the catalysts had significant loss. In addition, catalysts A to F have high activity and can effectively suppress side reactions such as hydrogenolysis to produce ethylbenzene and dehydration to produce styrene, and the catalysts of Comparative Examples 1 to 4 not only have low activity but also poor selectivity.