Catalyst for preparing tetrahydrofuran through continuous hydrogenation of furan as well as preparation and application of catalyst

Abstract

The invention discloses a catalyst for preparing tetrahydrofuran through continuous hydrogenation of furan. According to the invention, the catalyst consists of nickel, zinc oxide, cerium dioxide and silicon dioxide. Based on the mass percent of the catalyst, the catalyst comprises the following components in percentage by mass: 20-60% of Ni element, 0.5-5% of zinc oxide, 10-30% of cerium dioxide and the balance of silicon dioxide. The catalyst is prepared by adopting a coprecipitation method, the catalytic reaction condition required by the catalyst is mild, and the catalyst has the advantages of high low-temperature activity and high tetrahydrofuran selectivity and has a good industrial application prospect.

Description

Technical Field

[0001] The present invention relates to a catalyst for preparing tetrahydrofuran by continuous hydrogenation of furan; the present invention also relates to a method for preparing the catalyst; the present invention also relates to application of the catalyst in the reaction of preparing tetrahydrofuran by continuous hydrogenation of furan. Background Art

[0002] Tetrahydrofuran is widely used as a solvent due to its low toxicity, low boiling point, good fluidity and solubility. In addition, tetrahydrofuran is an important chemical used in the production of spandex and PTMEG, a raw material for polyurethane. At present, tetrahydrofuran is mainly obtained industrially by dehydration of 1,4-butanediol. Furan hydrogenation to prepare tetrahydrofuran is another production route.

[0003] US Patent 2033292 discloses a method for preparing tetrahydrofuran by catalyzing furan with an iron-based catalyst under high temperature and high pressure conditions in a liquid phase system, and ethanol needs to be used as a diluent during the reaction. Korean Patent KR1020200022575 discloses a method for preparing tetrahydrofuran by catalyzing furan hydrogenation with a Ru-Re bimetallic catalyst supported by biomass porous carbon, and the content of tetrahydrofuran in the product can reach about 70%. CN115445623A discloses a catalyst for preparing tetrahydrofuran by continuous hydrogenation of furan, and its preparation method and application. Using nickel promoted by silica-supported alkaline earth metal as a catalyst, furan is hydrogenated to tetrahydrofuran at 180-200°C and 2-10MPa pressure, and the maximum selectivity of tetrahydrofuran is about 96%. After the catalyst runs for 240 hours, the amount of residual furan in the product increases from 1% to 6.9%, indicating that the catalyst is slowly deactivated during operation. CN112547071A discloses a catalyst for preparing tetrahydrofuran by hydrogenation of furan, and its preparation method and application. A TiO2-Al2O3 composite carrier supports a nickel catalyst. Under the conditions of 210°C and 3MPa reaction pressure, the volumetric space velocity of furan liquid is 1h -1 When the hydrogen-to-oil molar ratio is 1000, the furan conversion rate is 98.09% and the tetrahydrofuran selectivity is 92.01%.

[0004] The disclosed patents have one or more of the following problems: use of precious metal catalysts, high reaction temperature, high reaction pressure, poor stability, low tetrahydrofuran selectivity, etc. In response to these problems, the present invention discloses a cheap metal nickel-based catalyst that catalyzes the continuous hydrogenation of furan to produce tetrahydrofuran with high selectivity under mild reaction conditions. The catalyst achieves a furan conversion rate of 98% while obtaining a tetrahydrofuran selectivity of not less than 99%, and the stability of the catalyst exceeds 1000 hours. Summary of the invention

[0005] In view of the low selectivity and stability of the existing furan hydrogenation to tetrahydrofuran, a supported inexpensive nickel-based catalyst with high low-temperature activity, high tetrahydrofuran selectivity and excellent stability and a method for preparing the catalyst are invented. The specific invention content is as follows:

[0006] In a preferred embodiment, the catalyst consists of nickel, zinc oxide, cerium dioxide and silicon dioxide.

[0007] In a preferred embodiment, the nickel content of the catalyst is 20-60% by mass of the catalyst, preferably 25-55%, more preferably 30-50%, and most preferably 40-50%; the zinc oxide content is 0.5-5% by mass of the catalyst, preferably 0.8-4.5%, more preferably 1-4%, and most preferably 2-3%; the cerium dioxide content is 10-30% by mass of the catalyst, preferably 13-27%, more preferably 16-25%, and most preferably 20-25%; the rest is silicon dioxide

[0008] A method for preparing a catalyst for preparing tetrahydrofuran by continuous hydrogenation of furan, characterized in that the catalyst is prepared by a coprecipitation method, specifically by the following steps:

[0009] a) dissolving the precursors of nickel, zinc and cerium in water and / or an organic solvent, stirring to mix them evenly, and obtaining a metal salt solution with a metal molar concentration of 0.2 to 2 mol / L;

[0010] b) adding silica sol and / or silicon dioxide solid to the mixed salt solution of step a) above, stirring and mixing evenly;

[0011] c) preparing a sodium hydroxide solution, a sodium carbonate solution, or a mixed solution of sodium hydroxide and sodium carbonate to obtain a precipitant solution having a sodium ion concentration of 0.4 to 4 mol / L;

[0012] d) adding the precipitant solution obtained in step c dropwise to the metal salt solution obtained in step b to perform precipitation operation, wherein the volume ratio of the precipitant solution to the metal salt solution is 1 to 4, and the mixture obtained after the precipitation is completed is aged and stirred at 50 to 80° C. for 1 to 10 hours, and filtered or filtered to obtain a filter cake, and the filter cake is washed until the filtrate is neutral;

[0013] e) drying the sample obtained in step d in an air atmosphere at a temperature of 50 to 150° C. (preferably 60 to 140° C., more preferably 70 to 130° C., most preferably 80 to 120° C.) for 4 to 48 hours (preferably 6 to 40 hours, more preferably 10 to 30 hours, most preferably 12 to 24 hours), and calcining at a temperature of 300 to 600° C. (preferably 350 to 550° C., more preferably 400 to 500° C., most preferably 425 to 475° C.) for 2 to 48 hours (preferably 3 to 36 hours, more preferably 4 to 24 hours, most preferably 4 to 10 hours) to obtain a catalyst precursor;

[0014] f) activating the catalyst precursor obtained in step e to obtain a catalyst for continuous hydrogenation of furan to tetrahydrofuran.

[0015] In a preferred embodiment, the activation treatment of the catalyst shown in step f is carried out in a hydrogen or hydrogen-containing mixed atmosphere, the hydrogen volume content in the activation treatment gas is 1 to 100%, and the gas other than hydrogen in the mixed gas is one or more of nitrogen, argon or helium; the space velocity of the hydrogen-containing mixed gas is 500 to 10000h -1 , preferably 700~8000h -1 , more preferably 1000 to 6000 hours -1 , most preferably 1000~4000h -1 , the activation temperature is 200-700°C, preferably 250-650°C, more preferably 300-600°C, most preferably 400-550°C, the activation time is 1-100 hours, preferably 3-80 hours, more preferably 5-60 hours, most preferably 12-48 hours, and the activation pressure is 0.1-5.0 MPa, preferably 0.1-4.0 MPa, more preferably 0.1-3.0 MPa, most preferably 0.1-1.0 MPa.

[0016] In a preferred embodiment, the catalyst is activated outside the reactor or in situ in the reactor.

[0017] In a preferred embodiment, the precursors of nickel, zinc and cerium are nitrates of nickel, zinc and cerium, respectively.

[0018] The invention discloses an application of a furan hydrogenation catalyst in catalyzing the continuous hydrogenation of furan to produce tetrahydrofuran.

[0019] In a preferred embodiment, the furan hydrogenation reaction is carried out under the following conditions: the reaction temperature is 50 to 200°C, preferably 60 to 170°C, more preferably 70 to 150°C, and most preferably 80 to 130°C; the reaction pressure is 0.1 to 6.0 MPa, preferably 0.5 to 5.0 MPa, more preferably 0.8 to 4.0 MPa, and most preferably 1 to 3.0 MPa; the space velocity is 0.01 to 6 h-1 , preferably 0.1~5h -1 , more preferably 0.5 to 4 hours -1 , the most preferred time is 0.5 to 2 hours -1 , the molar ratio of hydrogen to furan is 4-400, preferably 10-300, more preferably 20-200, and most preferably 30-60.

[0020] In a preferred embodiment, the continuous hydrogenation reaction of furan is carried out in a fixed bed reactor.

[0021] The catalyst is prepared by a co-precipitation method. The catalytic reaction conditions required by the catalyst are mild. It has the advantages of high low-temperature activity and high tetrahydrofuran selectivity, and has good industrial application prospects.

[0022] The beneficial effects of the present invention include but are not limited to the following: Compared with the existing catalyst for producing tetrahydrofuran by hydrogenating furan, the present invention constructs a nickel-zinc oxide-cerium dioxide-silicon dioxide multi-component composite catalyst, and the multi-component catalyst prepared by a co-precipitation method has excellent low-temperature furan hydrogenation activity and tetrahydrofuran selectivity, and gives the catalyst excellent long-range stability, thereby effectively improving the economic benefits of the reaction process of producing tetrahydrofuran by hydrogenating furan. DETAILED DESCRIPTION

[0023] The catalyst of the present invention is implemented according to the above steps, which are described in detail below through examples. The contents and percentages in this application are calculated by "mass" unless otherwise specified.

[0024] Example 1

[0025] Dissolve 49.5 g Ni(NO3)2·6H2O, 2.2 g Zn(NO3)2·6H2O, and 12.6 g Ce(NO3)3·6H2O in 170 ml water, stir evenly, and then add 14.7 g silica sol with a mass concentration of 30% to obtain a salt solution. Dissolve 33 g sodium carbonate in 310 ml deionized water to obtain a precipitant solvent. Under stirring conditions at 50°C, add the sodium carbonate solution dropwise to the metal salt solution at a rate of 10 ml / min. After the addition is completed, continue aging and stirring for 4 hours. Then filter, wash the filter cake with deionized water, and stop washing after washing until the filtrate is colorless. Dry the filter cake at 120°C for 10 hours to constant weight, and calcine at 400°C for 5 hours. The catalyst is prepared through granulation and tableting processes. The catalyst is labeled A and has a composition of 50Ni-3ZnO-25CeO2-22SiO2. The catalyst obtained above was applied to the continuous hydrogenation of furan to produce tetrahydrofuran. The catalyst was reduced in hydrogen at a temperature of 400°C, a reduction time of 4 h, a reduction pressure of 0.5 MPa, and a reduction gas space velocity of 1000 h -1; Furan hydrogenation reaction temperature 100℃, reaction pressure 1.5MPa, furan liquid hourly space velocity 1.0h -1 , hydrogen / furan molar ratio 50, and catalyst furan hydrogenation reaction results are listed in Table 1.

[0026] Example 2

[0027] Except that the amount of Zn(NO3)2·6H2O was changed to 1.5 g and the mass of 30% silica sol was changed to 15.3 g, the other steps (process and conditions) of catalyst preparation were the same as those in Example 1. The catalyst was labeled B and had a composition of 50Ni-2ZnO-25CeO2-23SiO2. The catalyst reaction conditions were the same as those in Example 1, and the results of the catalyst furan hydrogenation reaction were listed in Table 1.

[0028] Example 3

[0029] Except that the amount of Ce(NO3)3·6H2O was changed to 10.1 g and the mass of 30% silica sol was changed to 18 g, the other steps (process and conditions) of catalyst preparation were the same as those in Example 1. The catalyst was labeled C and had a composition of 50Ni-3ZnO-20CeO2-27SiO2. The catalyst reaction conditions were the same as those in Example 1, and the results of the catalyst furan hydrogenation reaction were listed in Table 1.

[0030] Example 4

[0031] Except that the amount of Ce(NO3)3·6H2O was changed to 11.6 g and the mass of 30% silica sol was changed to 16 g, the other steps (process and conditions) of catalyst preparation were the same as those in Example 1. The catalyst was labeled D and had a composition of 50Ni-3ZnO-23CeO2-24SiO2. The catalyst reaction conditions were the same as those in Example 1, and the results of the catalyst furan hydrogenation reaction were listed in Table 1.

[0032] Example 5

[0033] Except that the amount of Ni(NO3)2·6H2O was changed to 39.6 g and the mass of 30% silica sol was changed to 21.3 g, the other steps (process and conditions) of catalyst preparation were the same as those in Example 1. The catalyst was labeled E and had a composition of 40Ni-3ZnO-25CeO2-32SiO2. The catalyst reaction conditions were the same as those in Example 1, and the results of the catalyst furan hydrogenation reaction were listed in Table 1.

[0034] Example 6

[0035] Except that the precipitant in Example 1 is changed to sodium hydroxide, the other steps (process and conditions) of catalyst preparation are the same as those in Example 1. Specifically, 24.8 grams of sodium hydroxide is weighed and dissolved in 620 milliliters of water to obtain a precipitant solution. The catalyst is labeled F and has a composition of 50Ni-3ZnO-25CeO2-22SiO2. The catalyst reaction conditions are the same as those in Example 1, and the results of the catalyst furan hydrogenation reaction are listed in Table 1.

[0036] Example 7

[0037] Except that the precipitation aging temperature in Example 1 was changed to 70 degrees Celsius, the other steps (process and conditions) of catalyst preparation were the same as those in Example 1. The catalyst was labeled G and had a composition of 50Ni-3ZnO-25CeO2-22SiO2. The catalyst reaction conditions were the same as those in Example 1, and the results of the catalyst furan hydrogenation reaction were listed in Table 1.

[0038] Example 8

[0039] The composition and preparation process of the catalyst are the same as those in Example 1. The catalyst reaction conditions in Example 1 are changed to: the catalyst is reduced in hydrogen at a temperature of 450°C, a reduction time of 4h, a reduction pressure of 0.5MPa, and a reduction gas space velocity of 1000h -1 , furan hydrogenation reaction temperature 110℃, reaction pressure 3.0MPa, furan liquid hourly space velocity 2.0h -1 , hydrogen / furan molar ratio 30, and catalyst furan hydrogenation reaction results are listed in Table 1.

[0040] Example 9

[0041] The composition and preparation process of the catalyst are the same as those of Example 1. The catalyst reaction conditions of Example 1 are changed to: the catalyst is reduced in hydrogen at a temperature of 380°C, a reduction time of 10 h, a reduction pressure of 1.0 MPa, and a reduction gas space velocity of 1000 h -1 , furan hydrogenation reaction temperature 80℃, reaction pressure 3.0MPa, furan liquid hourly space velocity 0.5h -1 , hydrogen / furan molar ratio 60, and catalyst furan hydrogenation reaction results are listed in Table 1.

[0042] Example 10

[0043] The composition and preparation process of the catalyst are the same as those in Example 1. The catalyst reaction conditions in Example 1 are changed to: the catalyst is reduced in hydrogen at a temperature of 430°C, a reduction time of 24h, a reduction pressure of 0.1MPa, and a reduction gas space velocity of 1000h -1 , furan hydrogenation reaction temperature 130℃, reaction pressure 2.0MPa, furan liquid hourly space velocity 0.5h -1 , hydrogen / furan molar ratio 40, and the stability reaction results of the continuous operation of furan hydrogenation over the catalyst are listed in Table 2.

[0044] Comparative Example 1

[0045] Dissolve 49.5 g of Ni(NO3)2·6H2O in 130 ml of water, stir evenly, and then add 33.3 g of 30% silica sol to obtain a salt solution. Dissolve 27.1 g of sodium carbonate in 255 ml of deionized water to obtain a precipitant solvent. Under stirring conditions at 50°C, add the sodium carbonate solution dropwise to the metal salt solution at a rate of 10 ml / min. After the addition is complete, continue aging and stirring for 4 hours. Then filter, wash the filter cake with deionized water, and stop washing after washing until the filtrate is colorless. Dry the filter cake at 120°C for 10 hours to constant weight and calcine at 400°C for 5 hours. The catalyst is prepared by granulation and tableting processes. The catalyst is labeled H and has a composition of 50Ni-50SiO2. The above-obtained catalyst is used in the continuous hydrogenation of furan to produce tetrahydrofuran. The catalyst is reduced in hydrogen at a temperature of 400°C, a reduction time of 4h, a reduction pressure of 0.5MPa, and a reduction gas space velocity of 1000h. -1 , furan hydrogenation reaction temperature 100℃, reaction pressure 1.5MPa, furan liquid hourly space velocity 1.0h -1 , hydrogen / furan molar ratio 50, and catalyst furan hydrogenation reaction results are listed in Table 1.

[0046] Comparative Example 2

[0047] Dissolve 49.5 g of Ni(NO3)2·6H2O and 12.6 g of Ce(NO3)3·6H2O in 170 ml of water, stir evenly, and then add 16.7 g of 30% silica sol to obtain a salt solution. Dissolve 33 g of sodium carbonate in 310 ml of deionized water to obtain a precipitant solvent. Under stirring conditions at 50°C, add the sodium carbonate solution dropwise to the metal salt solution at a rate of 10 ml / min. After the addition is complete, continue aging and stirring for 4 hours. Then filter, wash the filter cake with deionized water, and stop washing after washing until the filtrate is colorless. Dry the filter cake at 120°C for 10 hours to constant weight, and calcine at 400°C for 5 hours. The catalyst is prepared through granulation and tableting processes. The catalyst is labeled I and has a composition of 50Ni-25CeO2-25SiO2. The catalyst obtained above was applied to the continuous hydrogenation of furan to tetrahydrofuran. The catalyst was reduced in hydrogen at a temperature of 400°C, a reduction time of 4h, a reduction pressure of 0.5MPa, and a reduction gas space velocity of 1000h -1 , furan hydrogenation reaction temperature 100℃, reaction pressure 1.5MPa, furan liquid hourly space velocity 1.0h -1 , hydrogen / furan molar ratio 50, and catalyst furan hydrogenation reaction results are listed in Table 1.

[0048] Comparative Example 3

[0049] Dissolve 49.5 g Ni(NO3)2·6H2O, 2.2 g Zn(NO3)2·6H2O, and 12.6 g Ce(NO3)3·6H2O in 170 ml water, stir evenly, and add 4.4 g 100-mesh coconut shell carbon powder to obtain a salt precursor suspension. Dissolve 33 g sodium carbonate in 310 ml deionized water to obtain a precipitant solvent. Under stirring at 50°C, add the sodium carbonate solution to the metal salt precursor suspension at a rate of 10 ml / min. After the addition is completed, continue aging and stirring for 4 hours. Then filter, wash the filter cake with deionized water, and stop washing after washing until the filtrate is colorless. Dry the filter cake at 120°C for 10 hours to constant weight and calcine at 400°C for 5 hours. Prepare the catalyst through granulation and tableting processes. The catalyst is labeled J and has a composition of 50Ni-3ZnO-25CeO2-22AC. The catalyst obtained above was applied to the continuous hydrogenation of furan to tetrahydrofuran. The catalyst was reduced in hydrogen at a temperature of 400°C, a reduction time of 4h, a reduction pressure of 0.5MPa, and a reduction gas space velocity of 1000h -1 , furan hydrogenation reaction temperature 100℃, reaction pressure 1.5MPa, furan liquid hourly space velocity 1.0h -1 , hydrogen / furan molar ratio 50, and catalyst furan hydrogenation reaction results are listed in Table 1.

[0050] Table 1 Furan hydrogenation performance of different catalysts

[0051]

[0052]

[0053] Table 2 Furan continuous hydrogenation stability data of Example 9

[0054] Response time / hour Furan conversion rate / % Tetrahydrofuran selectivity / % 24 99.91 99.52 96 99.86 99.49 168 99.76 99.69 240 99.43 99.61 312 99.57 99.48 384 99.29 99.57 456 99.74 99.44 528 99.65 99.61 600 99.59 99.39 672 99.40 99.47 744 99.29 99.46 816 99.76 99.55 888 99.49 99.61 960 99.32 99.51 1000 99.51 99.60

[0055] As can be seen from Table 1, the nickel-zinc oxide-cerium dioxide-silicon dioxide multi-component cheap metal catalyst of the present invention can be used to catalyze the hydrogenation of furan with high activity and high selectivity to prepare tetrahydrofuran, and the furan conversion rate exceeds 98 while obtaining a tetrahydrofuran selectivity of more than 99%. As can be seen from Table 2, the catalyst disclosed in the present invention has excellent stability, and no obvious performance degradation is found after the catalyst is operated for 1000 hours. Therefore, the catalyst provided by the present invention shows excellent activity, tetrahydrofuran selectivity and reaction stability in the continuous hydrogenation of furan to tetrahydrofuran reaction. The present invention shows performance superior to that of existing public patents in terms of reaction conditions, activity, product selectivity and stability, and has considerable industrial application prospects.

Claims

1. A catalyst for the continuous hydrogenation of furan to tetrahydrofuran, characterized in that: The catalyst consists of nickel, zinc oxide, cerium dioxide and silicon dioxide.

2. The catalyst according to claim 1, characterized in that: The nickel content of the catalyst is 20-60% of the catalyst mass, preferably 25-55%, more preferably 30-50%, most preferably 40-50%; The zinc oxide content is 0.5-5% of the catalyst mass, preferably 0.8-4.5%, more preferably 1-4%, most preferably 2-3%; The cerium dioxide content is 10-30% of the catalyst mass, preferably 13-27%, more preferably 16-25%, most preferably 20-25%; The rest is silicon dioxide.

3. A method for preparing the catalyst according to claim 1 or 2, characterized in that: The catalyst was prepared by coprecipitation method, specifically according to the following steps: a) dissolving the precursors of nickel, zinc and cerium in water, stirring to mix them evenly, and obtaining a metal salt solution with a metal molar concentration of 0.2 to 2 mol / L; b) adding silica sol and / or silicon dioxide solid to the mixed salt solution of step a) above, stirring and mixing evenly; c) preparing a sodium hydroxide solution, a sodium carbonate solution, or a mixed solution of sodium hydroxide and sodium carbonate to obtain a precipitant solution having a sodium ion concentration of 0.4 to 4 mol / L; d) adding the precipitant solution obtained in step c dropwise to the metal salt solution obtained in step b to perform precipitation operation, wherein the volume ratio of the precipitant solution to the metal salt solution is 1 to 4, and the mixture obtained after the precipitation is completed is aged and stirred at 50 to 80° C. for 1 to 10 hours, and filtered or filtered to obtain a filter cake, and the filter cake is washed until the filtrate is neutral; e) drying the sample obtained in step d in an air atmosphere at a temperature of 50 to 150° C. (preferably 60 to 140° C., more preferably 70 to 130° C., most preferably 80 to 120° C.) for 4 to 48 hours (preferably 6 to 40 hours, more preferably 10 to 30 hours, most preferably 12 to 24 hours), and calcining at a temperature of 300 to 600° C. (preferably 350 to 550° C., more preferably 400 to 500° C., most preferably 425 to 475° C.) for 2 to 48 hours (preferably 3 to 36 hours, more preferably 4 to 24 hours, most preferably 4 to 10 hours) to obtain a catalyst precursor; f) activating the catalyst precursor obtained in step e to obtain a catalyst for continuous hydrogenation of furan to tetrahydrofuran.

4. The method according to claim 3, characterized in that: The catalyst activation treatment in step f is carried out in a hydrogen or hydrogen-containing mixed atmosphere, the hydrogen volume content in the activation treatment gas is 1-100%, and the gas other than hydrogen in the mixed gas is one or more of nitrogen, argon or helium; the space velocity of the hydrogen-containing mixed gas is 500-10000h -1 , preferably 700~8000h -1 , more preferably 1000 to 6000 hours -1 , most preferably 1000~4000h -1 , the activation temperature is 200-700°C, preferably 250-650°C, more preferably 300-600°C, most preferably 400-550°C, the activation time is 1-100 hours, preferably 3-80 hours, more preferably 5-60 hours, most preferably 12-48 hours, and the activation pressure is 0.1-5.0 MPa, preferably 0.1-4.0 MPa, more preferably 0.1-3.0 MPa, most preferably 0.1-1.0 MPa.

5. The method according to claim 4, characterized in that: The catalyst is activated by activation outside the reactor or in situ activation in the reactor.

6. The method according to claim 3, characterized in that: The precursors of nickel, zinc and cerium in step a) are nitrates of nickel, zinc and cerium respectively.

7. Use of the catalyst according to claim 1 or 2 in catalyzing the continuous hydrogenation of furan to produce tetrahydrofuran.

8. The use according to claim 7, characterized in that: The furan hydrogenation reaction is carried out under the following conditions: the reaction temperature is 50-200°C, preferably 60-170°C, more preferably 70-150°C, most preferably 80-130°C, the reaction pressure is 0.1-6.0MPa, preferably 0.5-5.0MPa, more preferably 0.8-4.0MPa, most preferably 1-3.0MPa, and the space velocity is 0.01-6h -1 , preferably 0.1~5h -1 , more preferably 0.5 to 4 hours -1 , the most preferred time is 0.5 to 2 hours -1 , the molar ratio of hydrogen to furan is 4-400, preferably 10-300, more preferably 20-200, and most preferably 30-60.

9. According to the use described in claim 7 or 8, the continuous hydrogenation reaction of furan is carried out in a fixed bed reactor.

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