Hydrogenation catalyst as well as preparation method and application thereof

Abstract

The invention provides a hydrogenation catalyst and a preparation method and application thereof, and belongs to the technical field of hydrodeoxygenation catalyst preparation. The catalyst comprises a carrier, a deoxidation active center and a hydrogenation active center, the oxide of the deoxidation active center is selected from one or more of tungsten oxide, molybdenum oxide or phosphorus oxide; the metal of the hydrogenation active center is selected from one or more of palladium, platinum, ruthenium, nickel and cobalt. The invention also provides a preparation method of the hydrogenation catalyst. A special surface structure is adopted to stabilize an acid center, the selectivity of a hydrodeoxygenation path in a catalytic reaction process is adjusted, and the activity and stability of the catalyst are improved. The prepared catalyst can effectively catalyze waste grease and fatty acid ester to prepare aliphatic hydrocarbon or fatty alcohol.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogenation catalyst preparation, and specifically relates to a hydrogenation catalyst and a preparation method and application thereof. Background Art

[0002] The resource and energy utilization of waste cooking oil is one of the important ways to create a low-carbon circular economy. Converting waste oil into biomass fuel to replace traditional fossil fuels is the most promising technical route. In addition, converting waste oil into fine chemicals such as fatty alcohols is also a technical route with great practical application potential. (XN Xu, NNLuo, WH Wang, M. Bao and JS Wang, ACS Appl. Mater. Interfaces. (2024); T. Wang, Y. Xin, B. Chen, B. Zhang, S. Luan, M. Dong, Y. Wu, X. Cheng, Y.Liu, H. Liu and B. Han, Nat. Commun. 15 (2024) 2166-2176; V. Torres-Bujalance, CA Prieto, KE Rodriguez Espinoza and L. A, Energy&Fuels. 38 (2024) 4312-4324.). The production of hydrocarbon-based biofuels and related bulk chemicals from fatty acid esters is mainly done through catalytic hydrogenation, and highly active and selective heterogeneous hydrogenation catalysts are key. Currently, in the hydrogenation of fatty acid esters to produce aliphatic hydrocarbons and fatty alcohols, most catalysts with noble metals such as palladium, platinum, and ruthenium and non-metals such as nickel and cobalt as active centers are used.(LL Zhou, LY Zhang, JR Li, TT Xiao, PK Luo, XLA Su, HYCheng and FY Zhao, Fuel. 369 (2024) 131746-131757;JP Zhao, XC Cao,P. Liu, F. Long, S. Y. Wu, J. M. Xu and J. C. Jiang, Catal. Lett. 24 (2024)1-8;JA Hunns, LJ Durndell, XG Zhang, M. Konarova, AF Lee and K.Wilson, ACS Catal. 14 (2024) 7052-7061;SZ Ding, DLF Ainaga, M. Hu, BY Qiu, U. Khalid, C. D'Agostino, XX Ou, B. Spencer, XL Zhong, YNPeng, N. Hondow, C. Theodoropoulos, YL Jiao, CMA Parlett and XLFan, Nat. Commun. 15 (2024) 7718;S. Chen, M. Leng, Z. Liao, J. Zeng, H. Xieand G. Zhou, Ind. Crops Prod. 211 (2024) 118227-118238.)。In addition, the use of promoters such as molybdenum oxide, tungsten oxide, zinc oxide, copper oxide, and iron oxide can also change the catalytic structure and improve the activity and selectivity of the catalyst (CX Zhao, JJ Luo, WJ Zhu, Y. Li and CH Liang, Catal. Today. 437(2024) 114780-114789;M. Mukhtarova, MA Golubeva, AA Sadovnikov and AL Maximov, Appl. Catal., B. 351 (2024) 123999-124011;YH Cui, SY Yu, ZC Sun, HY Niu, CH Liang and C. Li, ACS Sustainable Chem. Eng. (2024)10340-10350;JW Chen, YM Xia, YX Ling, XH Liu, SY Li, X. Yin,LP Zhang, MH Liang, YM Yan, Q. Zheng, WX Chen, YJ Guo, EHYuan, GF Hu, XL Zhou and LY Wang, Nano Lett. 24 (2024) 5197-5205; G. Li, ACS Catal. 13 (2023) 13446-13455.).

[0003] Although the catalysts reported so far show good hydrogenation and deoxygenation activities in the process of hydrodeoxygenation of fatty acid esters to produce fatty hydrocarbons, it is still difficult to control the reaction process to only deoxygenate without decarboxylation, which usually leads to high selectivity of decarboxylation products. In addition, deactivation caused by structural changes and carbon deposition of the catalyst is also easy to occur. Therefore, it is still a challenge to prepare catalysts with high deoxygenation activity, selectivity and stability. Summary of the invention

[0004] The purpose of the present invention is to provide a hydrogenation catalyst and its preparation method and application. The present invention uses a special surface structure to adjust various active centers, change the selectivity in the catalytic process, inhibit decarboxylation in the hydrogenation process, and improve the activity selectivity. The catalyst prepared by the present invention can effectively catalyze fatty acid esters and waste oils to prepare fatty hydrocarbons or fatty alcohols.

[0005] The present invention first provides a hydrogenation catalyst, which includes a carrier, a deoxygenation active center and a hydrogenation active center; The oxide of the deoxidation active center is selected from one or more of tungsten oxide, molybdenum oxide or phosphorus oxide; The metal of the hydrogenation active center is selected from one or more of palladium, platinum, ruthenium, nickel or cobalt.

[0006] Preferably, the catalyst further comprises a promoter, and the promoter is selected from one or more of lanthanum oxide, cerium oxide, praseodymium oxide, zinc oxide, copper oxide, iron oxide, neodymium oxide or europium oxide.

[0007] Preferably, the carrier is selected from one or more of silicon oxide, titanium oxide or aluminum oxide.

[0008] Preferably, the metal content of the deoxygenation active center accounts for 1% to 40% of the total mass of the carrier; the metal content of the hydrogenation active center accounts for 0.5% to 10% of the total mass of the carrier; and the metal content of the co-catalyst accounts for 0.5% to 15% of the total mass of the carrier.

[0009] The present invention also provides a method for preparing a hydrogenation catalyst, comprising: Step 1: dissolving one or more of metal molybdenum salt, tungsten salt or phosphate in water to obtain a salt solution, then impregnating the solution on a carrier and drying the solution to obtain a precursor, and calcining the precursor to obtain an intermediate; Step 2: The solution of nitrate or chloride containing the hydrogenation active center metal is impregnated into the intermediate obtained in step 1 again, and then dried and calcined to obtain a hydrogenation catalyst.

[0010] Preferably, the molybdenum salt described in step 1 is ammonium heptamolybdate or ammonium molybdate, the tungsten salt is ammonium metatungstate, and the phosphate is ammonium phosphate.

[0011] Preferably, the calcination temperature in step 1 is 300-1000°C, the calcination time is 2-24 hours, and the heating rate is 1°C / min to 30°C / min; the calcination temperature in step 2 is 200-800°C, the calcination time is 2-24 hours, and the heating rate is 1°C / min to 30°C / min.

[0012] Preferably, when adding the promoter, in step 2, the solution containing the nitrate or chloride of the hydrogenation active center metal and the nitrate or chloride containing the promoter metal are dissolved and mixed uniformly.

[0013] Preferably, the mass ratio of the metal in the metal molybdenum salt, tungsten salt or phosphate, the metal in the hydrogenation active center and the metal in the promoter is (1-80):(1-20):1.

[0014] The present invention also provides the use of the hydrogenation catalyst in catalyzing the preparation of fatty hydrocarbons or fatty alcohols from fatty acid esters and waste oils.

[0015] Beneficial Effects of the Invention The present invention provides a hydrogenation catalyst and a preparation method and application thereof. The present invention adopts special components and surface structures to coordinate the hydrogenation active center and the deoxygenation active center of the catalyst to obtain excellent activity and selectivity. Compared with the prior art, the hydrogenation catalyst prepared by the present invention has not only Bronsted acid and Lewis acid sites constructed by one or more active species such as molybdenum, tungsten and phosphorus on the surface, but also has basic sites constructed by basic oxides. Compared with the hydrogenation catalysts currently reported in the literature, the deoxygenation selectivity is better and the decarboxylation product is less. It can show higher hydrogenation and deoxygenation efficiency and stability during the reaction process. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the X-ray powder diffraction pattern of the catalyst of Example 1 of the present invention; Figure 2 X-ray photoelectron spectrum of catalyst Mo in Example 1 of the present invention Figure 3 is the X-ray photoelectron spectrum of the catalyst Pd of Example 1 of the present invention; Figure 4 This is a NH3-TPD temperature desorption test diagram of the catalyst in Example 1 of the present invention; Figure 5 Pyridine infrared spectrum of the catalyst of Example 1 of the present invention Figure 6 This is a H2-TPD temperature desorption test diagram of the catalyst in Example 1 of the present invention; Figure 7 This is a H2-TPR temperature desorption test diagram of the catalyst in Example 1 of the present invention; Figure 8 This is a transmission electron microscope image of the catalyst of Example 1 of the present invention; Fig. 9 The gas chromatography test results of the hydrogenolysis of methyl stearate catalyzed by Example 1 of the present invention are as follows; Fig.10 This is the gas chromatography test result of the product of catalytic hydrogenolysis of methyl laurate in Example 1 of the present invention. DETAILED DESCRIPTION

[0017] The present invention first provides a hydrogenation catalyst, which includes a carrier, a deoxygenation active center and a hydrogenation active center; the oxide of the deoxygenation active center is selected from one or more of tungsten oxide, molybdenum oxide or phosphorus oxide; the metal of the hydrogenation active center is selected from one or more of palladium, platinum, ruthenium, nickel or cobalt.

[0018] According to the present invention, the catalyst preferably further comprises a promoter, and the promoter is preferably selected from one or more of lanthanum oxide, cerium oxide, praseodymium oxide, neodymium oxide, zinc oxide, copper oxide, iron oxide or europium oxide.

[0019] According to the present invention, the carrier is preferably selected from one or more of silicon oxide, titanium oxide or aluminum oxide.

[0020] According to the present invention, the metal content of the deoxygenation active center preferably accounts for 1% to 40% of the total mass of the carrier; the metal content of the hydrogenation active center preferably accounts for 0.5% to 10% of the total mass of the carrier; and the metal content of the co-catalyst preferably accounts for 0.5% to 15% of the total mass of the carrier.

[0021] The present invention also provides a method for preparing a solid hydrogenation catalyst, comprising: Step 1: dissolve one or more of metal molybdenum salt, tungsten salt or phosphate in water to obtain a salt solution, then impregnate it on a carrier and dry it. The drying temperature is preferably 80-150 °C, and the drying time is preferably 2-48 hours to obtain a precursor. After calcining the precursor, an intermediate is obtained. The molybdenum salt is preferably ammonium heptamolybdate or ammonium molybdate, the tungsten salt is preferably ammonium metatungstate, and the phosphate is preferably ammonium phosphate. The calcination temperature is preferably 300-1000 °C, the calcination time is preferably 2-24 hours, and the heating rate is preferably 1 °C / min-30 °C / min.

[0022] Step 2: impregnate the solution of nitrate or chloride containing hydrogenation active center metal into the intermediate obtained in step 1 again and dry it, or when adding a promoter, dissolve and mix the solution of nitrate or chloride containing hydrogenation active center metal and the nitrate or chloride of promoter metal evenly; the drying temperature is preferably 80-150°C, the drying time is preferably 2-48 hours, and calcination is performed. The calcination temperature is preferably 200-800°C, the calcination time is preferably 2-24 hours, and the heating rate is preferably 1°C / min ~ 30°C / min to obtain a hydrogenation catalyst; the solution of nitrate or chloride containing hydrogenation active center metal is preferably one or more of palladium chloride, platinum chloride, ruthenium chloride, nickel nitrate, and cobalt nitrate, and the promoter is preferably selected from one or more of lanthanum oxide, cerium oxide, praseodymium oxide, neodymium oxide, zinc oxide, copper oxide, iron oxide or europium oxide.

[0023] According to the present invention, the mass ratio of the metal in the metal molybdenum salt, tungsten salt or phosphate, the metal in the hydrogenation active center and the metal in the promoter is (1-80):(1-20):1.

[0024] According to the present invention, the impregnation method is preferably continuous impregnation or co-impregnation.

[0025] The present invention also provides the use of the hydrogenation catalyst in catalyzing the preparation of fatty acid esters to prepare fatty hydrocarbons, fatty alcohols and other bulk chemicals.

[0026] The present invention is described in detail below with reference to specific examples. The raw materials involved in the examples are all commercially available. Example 1

[0027] Weigh 1.0 g of ammonium heptamolybdate (tetrahydrate) and dissolve it in water. Dissolve it completely by ultrasonication and stir it evenly. Then add it dropwise into 10.0 g of Al2O3 powder. After impregnation, put it in an oven and dry it at 120°C for 3 hours to obtain precursor 1. Grind precursor 1 into powder and spread it flat on a quartz boat. Put it in a muffle furnace and calcine it at 500°C for 3 hours with a heating rate of 5°C / min. After natural cooling, obtain an intermediate.

[0028] Then weigh 0.1 g zinc nitrate (hexahydrate) and dissolve it in water and 0.3 g palladium chloride, ultrasonically dissolve it completely, stir it evenly and then add it dropwise to the intermediate, dry it at 120 °C for 3 hours to obtain precursor 2, grind precursor 2 into powder and spread it flat on a quartz boat, put it into a muffle furnace and calcine it at 300 °C for 3 h with a heating rate of 5 °C / min. After the calcination, cool it naturally to room temperature to obtain MoPdZn / Al2O3-1 hydrogenation catalyst.

[0029] Figure 1is the X-ray powder diffraction pattern of the catalyst of Example 1 of the present invention; Figure 1 This indicates that the catalyst prepared by the present invention has certain crystallinity, and its crystalline component is mainly the diffraction peak of alumina. After loading other components, the diffraction peak of XRD does not show obvious characteristic peaks.

[0030] Figure 2 is the X-ray photoelectron spectrum of the molybdenum element in the catalyst of Example 1 of the present invention; Figure 2 This indicates that the molybdenum component in the catalyst prepared by the present invention exists in the form of pentavalent and hexavalent molybdenum at the same time.

[0031] Figure 3 is the X-ray photoelectron spectrum of the palladium element in the catalyst of Example 1 of the present invention; Figure 3 This indicates that the palladium component in the catalyst prepared by the present invention exists in the form of both 0-valent palladium and +2-valent palladium.

[0032] Figure 4 This is a NH3-TPD temperature desorption test diagram of the catalyst in Example 1 of the present invention; Figure 4 This indicates that there are two different types of acid sites on the surface of the catalyst prepared by the present invention: weak acid sites between 150 and 350 °C, and strong acid sites above 400 °C.

[0033] Figure 5 This is the pyridine infrared spectrum of the catalyst of Example 1 of the present invention; Figure 5 This indicates that significant Bronsted acid and Lewis acid sites exist on the surface of the catalyst prepared by the present invention.

[0034] Figure 6 This is a graph of the H2-TPD temperature desorption test of the catalyst in Example 1 of the present invention; Figure 6 This indicates that the catalyst surface prepared by the present invention has good hydrogen adsorption and activation capabilities.

[0035] Figure 7 This is a temperature rise desorption test diagram of the catalyst H2-TPR of Example 1 of the present invention; Figure 7 The reduction temperature of the catalyst prepared by the present invention is explained, indicating that the catalyst can be reduced at a lower temperature.

[0036] Figure 8 This is a transmission electron microscope photo of the catalyst of Example 1 of the present invention; Figure 8 This indicates that the metal components in the catalyst prepared by the present invention have good dispersion and crystallinity. Example 2

[0037] Weigh 1.84 g of ammonium heptamolybdate (tetrahydrate) and dissolve it in water, dissolve it completely by ultrasonication, stir it evenly, then add it dropwise to 10.0 g of Al2O3, put it in an oven and dry it at 120 °C for 3 hours to obtain precursor 1, grind precursor 1 into powder and spread it in a quartz boat, put it in a muffle furnace, calcine it at 550 °C for 3 hours, the heating rate is 5 °C / min, and the intermediate is obtained after natural cooling. Weigh 0.1 g of zinc nitrate (hexahydrate) and dissolve it in water, add 0.3 g of palladium chloride, dissolve it completely by ultrasonication, stir it evenly, then add it dropwise to the intermediate, dry it at 120 °C for 3 hours to obtain precursor 2, grind precursor 2 into powder and spread it in a quartz boat, put it in a muffle furnace and calcine it at 450 °C for 3 hours, and cool it to room temperature naturally to obtain MoPdZn / Al2O3-2 hydrogenation catalyst. Example 3

[0038] Weigh 1.84 g of ammonium heptamolybdate (tetrahydrate) and dissolve it in water. Dissolve it completely by ultrasonication and stir it evenly. Then, add it dropwise into 10.0 g of nano-silicon dioxide. After impregnation, put it in an oven and dry it at 120 °C for 3 hours to obtain precursor 1. Grind precursor 1 into powder and spread it flat on a quartz boat. Put it in a muffle furnace and calcine it at 450 °C for 3 hours with a heating rate of 5 °C / min. After natural cooling, obtain an intermediate. Weigh 0.3 g of palladium chloride, dissolve it completely by ultrasonic treatment, stir it evenly and then add it dropwise to the intermediate, then weigh 0.3 g of nickel nitrate (hexahydrate) and dissolve it in water, dissolve it completely by ultrasonic treatment, stir it evenly and then add it dropwise to the intermediate, dry it at 120 °C for 3 hours to obtain precursor 2, grind precursor 2 into powder and spread it flat on a quartz boat, put it into a muffle furnace and calcine it at 650 °C for 6 hours, and cool it naturally to room temperature to obtain MoPdNiSiO2-1 solid acid catalyst. Example 4

[0039] Weigh 3 g of ammonium metatungstate and dissolve it in water, dissolve it completely by ultrasonication, stir it evenly, then add it dropwise to 10.0 g of nano-silicon dioxide, put it in an oven and dry it at 120 °C for 3 hours to obtain precursor 1, grind precursor 1 into powder and spread it flat in a quartz boat, put it in a muffle furnace, calcine it at 500 °C for 3 hours, the heating rate is 5 °C / min, and the intermediate is obtained after natural cooling. Then weigh 0.30 g of zinc nitrate (hexahydrate) and dissolve it in water, add 0.2 g of palladium chloride, dissolve it completely by ultrasonication, stir it evenly, then add it dropwise to the impregnated intermediate, dry it at 120 °C for 3 hours to obtain precursor 2, grind precursor 2 into powder and spread it flat in a quartz boat, put it in a muffle furnace and calcine it at 350 °C for 6 hours, the heating rate is 5 °C / min, and after the calcination, cool it naturally to room temperature to obtain WPdZn / γ-SiO2-1 hydrogenation catalyst. Example 5

[0040] Weigh 1.84 g of ammonium heptamolybdate (tetrahydrate) and dissolve it in water, dissolve it completely by ultrasonication, stir it evenly, then add it dropwise to 10.0 g of Al2O3, put it in an oven and dry it at 120 °C for 3 hours to obtain precursor 1, grind precursor 1 into powder and spread it in a quartz boat, put it in a muffle furnace, calcine it at 450 °C for 3 hours, the heating rate is 5 °C / min, and the intermediate is obtained after natural cooling. Weigh 0.2 g of palladium chloride and dissolve it in water, dissolve it completely by ultrasonication, stir it evenly, then add it dropwise to the impregnated intermediate, dry it at 120 °C for 3 hours to obtain precursor 2, grind precursor 2 into powder and spread it in a quartz boat, put it in a muffle furnace and calcine it at 350 °C for 3 hours, the heating rate is 5 °C / min, after the calcination, cool it naturally to room temperature, and MoPd / Al2O3-1 hydrogenation catalyst. Example 6

[0041] Weigh 1.84 g of ammonium heptamolybdate (tetrahydrate) and dissolve it in water. Weigh 0.5 g of ammonium phosphate and dissolve it in water by ultrasonication to completely dissolve it. Stir evenly, then add it dropwise into 10.0 g of γ-Al2O3. After impregnation, put it in an oven and dry it at 120 °C for 3 hours to obtain precursor 1. Grind precursor 1 into powder and spread it flat on a quartz boat, put it in a muffle furnace, and calcine it at 450 °C for 3 hours with a heating rate of 5 °C / min. After natural cooling, an intermediate is obtained. Weigh 0.3 g of lanthanum nitrate (hexahydrate) and dissolve it in water, add 0.2 g of palladium chloride, and completely dissolve it by ultrasonication. After stirring evenly, add it dropwise to the intermediate and impregnate it. Dry it at 120 °C for 3 hours to obtain precursor 2. Grind precursor 2 into powder and spread it flat on a quartz boat. Put it in a muffle furnace and calcine it at 650 °C for 8 hours. Cool it naturally to room temperature to obtain MoPPdLa / γ-Al2O3-1 hydrogenation catalyst. Example 7

[0042] In a 50 ml autoclave, 0.15 g of methyl stearate, 75 mg of the catalyst in Example 1, and 15 ml of n-hexane were added, and a 5 MPa 20% H2 / Ar mixed gas was introduced. The reaction was carried out at a stirring rate of 700 rpm and at 270 degrees for 14 hours. Alkyl bio-aviation fuel was obtained by separation. The product was analyzed by gas chromatography internal standard method. The alkane yield was 100%, of which C 18 The yield of alkane is 92%. Fig. 9 shown. Example 8

[0043] In a 50 ml autoclave, 0.15 g of methyl palmitate, 75 mg of the catalyst in Example 1, and 15 ml of n-hexane were added, and a 5 MPa 20% H2 / Ar mixed gas was introduced. The reaction was carried out at 270 degrees for 12 hours at a stirring rate of 700 rpm to obtain alkyl bio-aviation fuel. The product was analyzed by gas chromatography internal standard method, and the alkane yield was 100%, of which C 16 The yield of alkanes was 88%. Example 9

[0044] In a 50 ml autoclave, 0.15 g of methyl laurate, 75 mg of the catalyst in Example 1, and 15 ml of n-hexane were added, and a 5 MPa 20% H2 / Ar mixed gas was introduced. The mixture was stirred at a rate of 700 rpm and reacted at 270 degrees for 12 hours. Alkyl bio-aviation fuel was obtained by separation. The product was analyzed by gas chromatography internal standard method. The alkane yield was 100%, of which C 12 The yield of alkane is 90%. Fig.10 shown. Example 10

[0045] In a 50 ml autoclave, 0.15 g of methyl stearate, 75 mg of the catalyst in Example 3, and 15 ml of n-hexane were added, and a 5 MPa 20% H2 / Ar mixed gas was introduced. The reaction was carried out at 250 degrees Celsius at a stirring rate of 700 rpm for 6 hours. Alkyl bio-jet fuel was obtained by separation. The product was analyzed by gas chromatography internal standard method. 18 The yield of fatty alcohol is 90%.

Claims

1. A hydrogenation catalyst, characterized in that The catalyst comprises a carrier, a deoxygenation active center and a hydrogenation active center; The oxide of the deoxidation active center is selected from one or more of tungsten oxide, molybdenum oxide or phosphorus oxide; The metal of the hydrogenation active center is selected from one or more of palladium, platinum, ruthenium, nickel or cobalt.

2. A hydrogenation catalyst according to claim 1, characterized in that The catalyst also includes a promoter, and the promoter is selected from one or more of lanthanum oxide, cerium oxide, praseodymium oxide, zinc oxide, copper oxide, iron oxide, neodymium oxide or europium oxide.

3. A hydrogenation catalyst according to claim 1, characterized in that The carrier is selected from one or more of silicon oxide, titanium oxide or aluminum oxide.

4. A hydrogenation catalyst according to claim 2, characterized in that: The metal content of the deoxygenation active center accounts for 1% to 40% of the total mass of the carrier; the metal content of the hydrogenation active center accounts for 0.5% to 10% of the total mass of the carrier; and the metal content of the promoter accounts for 0.5% to 15% of the total mass of the carrier.

5. The method for preparing a hydrogenation catalyst according to claim 1, characterized in that: include: Step 1: dissolving one or more of metal molybdenum salt, tungsten salt or phosphate in water to obtain a salt solution, then impregnating the solution on a carrier and drying the solution to obtain a precursor, and calcining the precursor to obtain an intermediate; Step 2: The solution of nitrate or chloride containing the hydrogenation active center metal is impregnated into the intermediate obtained in step 1 again, and then dried and calcined to obtain a hydrogenation catalyst.

6. The method for preparing a hydrogenation catalyst according to claim 5, characterized in that: The molybdenum salt described in step 1 is ammonium heptamolybdate or ammonium molybdate, the tungsten salt is ammonium metatungstate, and the phosphate is ammonium phosphate.

7. The method for preparing a hydrogenation catalyst according to claim 5, characterized in that: The calcination temperature in step 1 is 300-1000°C, the calcination time is 2-24 hours, and the heating rate is 1°C / min to 30°C / min; the calcination temperature in step 2 is 200-800°C, the calcination time is 2-24 hours, and the heating rate is 1°C / min to 30°C / min.

8. The method for preparing a hydrogenation catalyst according to claim 5, characterized in that: When adding the promoter, in step 2, the solution containing the nitrate or chloride of the hydrogenation active center metal and the nitrate or chloride containing the promoter metal are dissolved and mixed uniformly.

9. The method for preparing a hydrogenation catalyst according to claim 5, characterized in that: The mass ratio of the metal in the metal molybdenum salt, tungsten salt or phosphate, the metal in the hydrogenation active center and the metal in the promoter is (1-80):(1-20):

1.

10. Use of the hydrogenation catalyst according to claim 1 in catalyzing the preparation of aliphatic hydrocarbons or fatty alcohols from fatty acid esters and waste oils.

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