Hydrogenation catalyst as well as preparation method and application thereof

Abstract

The invention provides a hydrogenation catalyst as well as a preparation method and application thereof. The hydrogenation catalyst comprises a carrier and an active component loaded on the carrier, the carrier comprises magnesium oxide and nickel oxide, and the active component comprises a transition metal of the VIII family; preferably, the active component comprises one or more of Pd, Pt or Ru; preferably, the active component is Pd. According to the invention, magnesium oxide and nickel oxide are used as the composite carrier, and when the catalyst is applied to 4-CBA hydrogenation reaction, the composite carrier and the active component have a synergistic effect, so that the selectivity of the active component to p-hydroxymethylbenzoic acid can be improved.

Description

Technical Field

[0001] This invention relates to the field of catalyst technology, specifically to a hydrogenation catalyst, its preparation method, and its application. Background Technology

[0002] Purified terephthalic acid (PTA) is an important raw material for the production of polyesters, plasticizers, and engineering plastics, and domestic demand for PTA is increasing at a rate of over 10% annually. Because crude terephthalic acid (CTA) contains p-carboxybenzaldehyde (4-CBA), it must be refined before it can be used in polyester production. Crude terephthalic acid (CTA) is generally prepared into PTA through catalytic hydrogenation refining; however, existing CTA hydrogenation refining catalysts do not provide ideal catalytic conversion of 4-CBA, resulting in a low conversion rate. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a hydrogenation catalyst, its preparation method, and its application.

[0004] In a first aspect, the present invention provides a hydrogenation catalyst comprising a support and an active component supported on the support, the support comprising magnesium oxide and nickel oxide, and the active component comprising a group VIII transition metal.

[0005] In some embodiments, the active component includes one or more of Pd, Pt, and Ru.

[0006] In some embodiments, the active component is Pd.

[0007] In some embodiments, the mass of the active component is 1.5-5% of the carrier, for example, 1.5%, 1.7%, 1.9%, 2.1%, 2.3%, 2.5%, 2.7%, 2.9%, 3%, 3.5%, 4%, 4.5%, 5% or any value between them.

[0008] In some embodiments, the mass ratio of nickel to magnesium in the carrier is 20:1 to 1:20, for example, 20:1, 17:1, 15:1, 13:1, 11:1, 9:1, 7:1, 5:1, 3:1, 1:1, 1:2.5, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, 1:20 or any value between them.

[0009] In some embodiments, the mass ratio of nickel to magnesium in the carrier is 5:1 to 1:5.

[0010] In some embodiments, the mass ratio of nickel to magnesium in the carrier is 2.5:1 to 1:2.5.

[0011] In some embodiments, the mass ratio of nickel to magnesium in the carrier is 1:1 to 1:2, for example, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2 or any value between them.

[0012] In some embodiments, the magnesium content in the hydrogenation catalyst is 20-60 wt%, for example, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, 58 wt%, or any value between them.

[0013] In a second aspect, the present invention provides a method for preparing a hydrogenation catalyst, comprising the following steps: preparing a support comprising magnesium oxide and nickel oxide; loading an active component onto the support to obtain a catalyst precursor loaded with the active component; and subjecting the precursor loaded with the active component to a reduction reaction.

[0014] In some embodiments, the reduction reaction uses a reducing agent.

[0015] In some embodiments, the reducing agent is selected from one or more of hydrazine hydrate, sodium formate, H2, or CO.

[0016] In some embodiments, when the reducing agent is hydrazine hydrate, an aqueous solution of hydrazine hydrate with a mass concentration of 70-85 wt% is used.

[0017] In some embodiments, the temperature of the reduction reaction is 80-120°C, for example 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C or any value between them.

[0018] In some embodiments, the reduction reaction takes 1-5 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours or any value between them.

[0019] In some embodiments, the mass ratio of the reducing agent to the catalyst precursor supported on the active component is 0.3-1.5, for example, 0.35, 0.5, 0.7, 0.9, 1.1, 1.3, 1.5 or any value between them.

[0020] In some embodiments, the method for preparing the support comprising magnesium oxide and nickel oxide includes the following steps:

[0021] (1) Mix the aqueous solution containing nickel salt and magnesium salt with the alkaline aqueous solution, filter, and obtain the carrier precursor;

[0022] (2) The carrier precursor is calcined.

[0023] In some embodiments, the nickel salt is selected from one or more of nickel nitrates, acetates, sulfates, or chlorides.

[0024] In some embodiments, the nickel salt is selected from one or more of nickel nitrate hexahydrate, nickel acetate tetrahydrate, nickel chloride hexahydrate, nickel sulfate hexahydrate, nickel sulfate heptahydrate, and nickel ammonium sulfate hexahydrate.

[0025] In some embodiments, the magnesium salt is selected from one or more of magnesium nitrates, acetates, sulfates, or chlorides.

[0026] In some embodiments, the magnesium salt is selected from one or more of magnesium nitrate hexahydrate, magnesium acetate tetrahydrate, magnesium chloride hexahydrate, and anhydrous magnesium sulfate.

[0027] In some embodiments, the alkaline aqueous solution is selected from one or more of sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, potassium hydroxide aqueous solution, or barium hydroxide aqueous solution.

[0028] In some embodiments, the mass ratio of nickel in the nickel salt to magnesium in the magnesium salt is 20:1 to 1:20, for example, 20:1, 17:1, 15:1, 13:1, 11:1, 9:1, 7:1, 5:1, 3:1, 1:1, 1:2.5, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, 1:20 or any value between them.

[0029] In some embodiments, the mass ratio of nickel in the nickel salt to magnesium in the magnesium salt is 5:1 to 1:5.

[0030] In some embodiments, the mass ratio of nickel in the nickel salt to magnesium in the magnesium salt is 2.5:1 to 1:2.5.

[0031] In some embodiments, the mass ratio of nickel in the nickel salt to magnesium in the magnesium salt is 1:1 to 1:2, for example, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2 or any value between them.

[0032] In some embodiments, the concentration of the alkaline aqueous solution is 50-100 g / L, for example, 60 g / L, 70 g / L, 80 g / L, 90 g / L, 100 g / L or any value between them.

[0033] In some embodiments, step (1) includes mixing by adding an alkaline aqueous solution to an aqueous solution containing nickel and magnesium salts using an alkaline burette.

[0034] In some embodiments, the dripping rate is 5-15 mL / min, for example, 5 mL / min, 7 mL / min, 9 mL / min, 11 mL / min, 13 mL / min, 15 mL / min or any value between them.

[0035] In some embodiments, the calcination temperature is 500-1000°C, for example, 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C or any value between them.

[0036] In some embodiments, the calcination time is 5-15 hours, for example, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours or any value between them.

[0037] In some embodiments, the roasting is carried out in a muffle furnace.

[0038] In some embodiments, the step of loading the active component onto the support includes mixing the support with an aqueous solution of a transition metal salt containing the active component.

[0039] In some embodiments, the transition metal salt containing the active component is selected from one or more transition metal nitrates, acetates, sulfates, or transition metal-containing organic compounds.

[0040] In some embodiments, the transition metal salt containing the active component is selected from one or more of platinum nitrate, platinum acetate, platinum sulfate, ruthenium chloride, ruthenium nitrate, ruthenium acetate, palladium nitrate dihydrate, palladium acetate, palladium chloride, palladium sulfate, or palladium acetylacetonate.

[0041] In some embodiments, the mass ratio of the transition metal salt containing the active component to the support is 1:10 to 1:25, for example, 1:10, 1:13, 1:16, 1:19, 1:22, 1:25 or any value between them.

[0042] In some embodiments, after loading the active component onto the support, the solvent is removed using a rotary evaporator.

[0043] In some embodiments, the temperature of the rotary evaporator is 60-90°C, for example, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C or any value between them.

[0044] In some embodiments, the rotational speed of the rotary evaporator is 20-50 r / min, for example, 20 r / min, 30 r / min, 40 r / min, 50 r / min or any value between them.

[0045] In a third aspect, the application of the hydrogenation catalyst described in the first aspect or the hydrogenation catalyst prepared by the preparation method described in the second aspect in the catalytic hydrogenation reaction of 4-CBA is provided.

[0046] In some embodiments, the temperature of the hydrogenation reaction is 200–250°C; for example, 200°C, 210°C, 220°C, 230°C, 240°C, 25°C, or any value between them.

[0047] In some embodiments, the pressure of the hydrogenation reaction is 10 to 15 bar; for example, 10 bar, 11 bar, 12 bar, 13 bar, 14 bar, 15 bar or any value between them.

[0048] In some embodiments, the hydrogenation reaction time is 120 to 130 min, for example 120 min, 121 min, 122 min, 123 min, 124 min, 125 min, 126 min, 127 min, 128 min, 129 min, 130 min or any value between them.

[0049] This invention uses magnesium oxide and nickel oxide as a composite support. When applied to the hydrogenation reaction of 4-CBA, the synergistic effect between the composite support and the active component can improve the selectivity of the active component for p-hydroxymethylbenzoic acid (HMBA). Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way.

[0051] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0052] Unless otherwise defined, the technical terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art. Unless otherwise specified, the reagents used in the following embodiments are conventional biochemical reagents; the raw materials, instruments, and equipment used in the following embodiments can all be obtained commercially or by existing methods; unless otherwise specified, the reagent dosages are those used in routine experimental operations; unless otherwise specified, the experimental methods are conventional methods.

[0053] The contents of Pd, Ni, and Mg elements in all embodiments and comparative examples of this invention were obtained by ICP testing. The inductively coupled plasma atomic emission spectrometer (ICP) used in this invention was a PerkinElmer 8300. The elemental contents, expressed as mass percentages, were determined by dissolving the analytical samples in aqua regia.

[0054] Example 1

[0055] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 5 g of nickel nitrate hexahydrate and 15 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0056] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 3.55g of catalyst solid. According to ICP testing, the catalyst contains 2.3 wt% Pd, 38.1 wt% magnesium, and 27.0 wt% nickel, as shown in Table 1.

[0057] Example 2

[0058] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 11.2 g of nickel nitrate hexahydrate and 4.7 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at a rate of 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0059] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to obtain the catalyst. The parameters are shown in Table 1.

[0060] Example 3

[0061] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 8.8 g of nickel nitrate hexahydrate and 9.4 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at a rate of 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0062] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to obtain the catalyst. The parameters are shown in Table 1.

[0063] Example 4

[0064] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 6.2 g of nickel nitrate hexahydrate and 13.2 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at a rate of 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0065] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to obtain the catalyst. The parameters are shown in Table 1.

[0066] Example 5

[0067] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 2.3 g of nickel nitrate hexahydrate and 19.5 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at a rate of 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0068] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to obtain the catalyst. The parameters are shown in Table 1.

[0069] Example 6

[0070] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 1.9 g of nickel nitrate hexahydrate and 20.2 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at a rate of 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0071] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to obtain the catalyst. The parameters are shown in Table 1.

[0072] Example 7

[0073] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 5 g of nickel nitrate hexahydrate and 15 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0074] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.45g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 3.64g of catalyst solid, as shown in Table 1.

[0075] Example 8

[0076] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 5 g of nickel nitrate hexahydrate and 15 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.7 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.6 g of carrier.

[0077] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.13g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 3.53g of catalyst solid, as shown in Table 1.

[0078] Comparative Example 1

[0079] Carrier preparation: (1) Add 14.2g of nickel nitrate hexahydrate to 500mL of deionized water in a 1L beaker, and stir thoroughly for 3h with a magnetic stirrer (300r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4g of NaOH solid in 50mL of deionized water, and stir thoroughly for 1h at 300r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10mL / min, and then stir thoroughly for 30min at a rate of 300r / min. After sufficient precipitation, filter. Then wash 10 times with 500mL of deionized water and filter to obtain 3.7g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800℃ in a muffle furnace for 8h. After cooling, remove the carrier to obtain 3.6g of carrier.

[0080] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 3.53g of solid catalyst.

[0081] Comparative Example 2

[0082] Carrier preparation: (1) Add 23g of magnesium nitrate hexahydrate to 500mL of deionized water in a 1L beaker and stir thoroughly for 3h with a magnetic stirrer (300r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4g of NaOH solid in 50mL of deionized water and stir thoroughly for 1h at 300r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10mL / min, and then stir thoroughly for 30min at a rate of 300r / min. After sufficient precipitation, filter. Then wash 10 times with 500mL of deionized water and filter to obtain 3.7g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine it in a muffle furnace at 800℃ for 8h. After cooling, remove it to obtain 3.6g of carrier.

[0083] Carrier loading of active components: (1) Add 3.6g of the carrier prepared above, 100mL of deionized water, and 0.2g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.7g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.7g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 3.57g of catalyst solid.

[0084] Comparative Example 3

[0085] One-pot preparation of catalyst: (1) Add 5g nickel nitrate hexahydrate, 15g magnesium nitrate hexahydrate, and 0.2g palladium nitrate dihydrate to 600mL of deionized water in a 1L beaker. Stir thoroughly for 3h using a magnetic stirrer (300r / min) until completely dissolved to obtain a catalyst precursor solution; (2) Dissolve 4g NaOH solid in 50mL of deionized water and stir thoroughly for 1h at 300r / min to obtain a NaOH solution; (3) Add the above NaOH solution dropwise to the catalyst precursor solution at 10mL / min using an alkaline burette. Then stir thoroughly for 30min at 300r / min. After sufficient precipitation, filter. Wash 10 times with 500mL of deionized water and filter to obtain 3.8g of composite metal hydroxide; (4) Place the catalyst precursor in a crucible and calcine at 800℃ in a muffle furnace for 8h. After cooling, remove the calcined metal to obtain 3.7g of metal oxide.

[0086] Reduction of active components: (1) Add 3.8g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst. The speed is 100r / min, the temperature is set to 100℃, and the stirring and heating time is 2h; (2) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in an oven at 100℃ to finally obtain 3.58g of catalyst solid.

[0087] Comparative Example 4

[0088] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 5 g of nickel nitrate hexahydrate and 11 g of aluminum nitrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at a rate of 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 3.9 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the substrate to obtain 3.8 g of carrier.

[0089] Carrier loading of active components: (1) Add 4.8g of the carrier prepared above, 100mL of deionized water, and 0.22g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 3.9g of solid powder from the inside and wall of the rotary evaporator; (3) Add 4.85g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 3.8g of catalyst solid, as shown in Table 1.

[0090] Comparative Example 5

[0091] Carrier preparation: (1) Add 500 mL of deionized water to a 1 L beaker, then add 8 g of aluminum nitrate and 15 g of magnesium nitrate hexahydrate. Stir thoroughly for 3 h with a magnetic stirrer (300 r / min) until completely dissolved to obtain a carrier precursor solution; (2) Dissolve 4 g of NaOH solid in 50 mL of deionized water and stir thoroughly for 1 h at 300 r / min to obtain a NaOH solution; (3) Use an alkaline burette to add the above NaOH solution dropwise to the carrier precursor solution at a rate of 10 mL / min, then stir thoroughly for 30 min at 300 r / min. After sufficient precipitation, filter. Then wash 10 times with 500 mL of deionized water and filter to obtain 4.3 g of carrier precursor; (4) Place the carrier precursor in a crucible and calcine at 800 °C in a muffle furnace for 8 h. After cooling, remove the carrier to obtain 4.2 g of carrier.

[0092] Carrier loading of active components: (1) Add 3.5g of the carrier prepared above, 100mL of deionized water, and 0.24g of palladium nitrate dihydrate to a beaker and stir thoroughly at 300r / min for 4h to obtain a mixed solution; (2) Transfer the above mixed solution to a rotary evaporator, set the temperature of the rotary evaporator to 80℃ and the rotation speed to 30r / min, until the solution evaporates to dryness. Finally, remove 4.3g of solid powder from the inside and wall of the rotary evaporator; (3) Add 3.5g of solid powder, 2g of hydrazine hydrate aqueous solution (80wt%), and 50mL of deionized water to a beaker. Use a magnetic stirrer with heating function to stir and heat the solution to reduce the catalyst, with a rotation speed of 100r / min, a temperature of 100℃, and a stirring and heating time of 2h; (4) Filter the solid in the beaker, wash it 10 times with 500mL of deionized water, and dry it in a 100℃ oven to finally obtain 4.2g of catalyst solid, as shown in Table 1.

[0093] Catalyst evaluation: 3 g of the catalyst prepared in the above examples and comparative examples, 150 mL of deionized water, and 4 g of 4-CBA were added to a 200 mL dynamically pressurized reactor. The reactor was purged with nitrogen and pressurized to 10 bar. After heating to 250 °C, hydrogen gas was introduced until the pressure reached 3 MPa (hydrogen partial pressure 2 MPa), and the reaction time was 2 h. After the reaction, the conversion rate of 4-CBA and the selectivity of p-hydroxymethylbenzoic acid (HMBA) were analyzed by chromatography, as shown in Table 1.

[0094] Table 1

[0095]

[0096]

[0097] In Table 1, the Pd content refers to the percentage of Pd element in the mass of the catalyst.

[0098] The nickel-to-magnesium mass ratio in Table 1 refers to the mass ratio of nickel to magnesium elements in the catalyst.

[0099] The nickel-aluminum mass ratio refers to the mass ratio of nickel to aluminum elements in the catalyst.

[0100] The aluminum-magnesium mass ratio refers to the mass ratio of aluminum to magnesium in the catalyst.

[0101] As shown in Table 1, the hydrogenation catalyst of the present invention can improve the conversion rate of 4-CBA and enhance the selectivity of the active component for HMBA in the catalytic hydrogenation reaction of 4-CBA.

[0102] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A hydrogenation catalyst comprising a support and an active component supported on the support, the support comprising magnesium oxide and nickel oxide, and the active component comprising a group VIII transition metal; Preferably, the active component includes one or more of Pd, Pt, or Ru; Preferably, the active component is Pd.

2. The hydrogenation catalyst according to claim 1, characterized in that, The active component comprises 1.5-5% of the hydrogenation catalyst by mass; and / or In the carrier, the mass ratio of nickel to magnesium is 20:1-1:20; preferably 5:1-1:5; more preferably 2.5:1-1:2.5; even more preferably 1:1-1:2; and / or The magnesium content in the hydrogenation catalyst is 20-60 wt%, preferably 20-50 wt%, and more preferably 25-45 wt%.

3. A method for preparing a hydrogenation catalyst, comprising the following steps: Preparation of a support comprising magnesium oxide and nickel oxide; The active component is loaded onto the support to obtain a catalyst precursor loaded with the active component; The precursor loaded with the active component is subjected to a reduction reaction.

4. The preparation method according to claim 3, characterized in that, The reduction reaction uses a reducing agent; Preferably, the reducing agent is selected from one or more of hydrazine hydrate, sodium formate, H2, or CO; and / or The reduction reaction is carried out at a temperature of 80-120°C; and / or The reduction reaction takes 1-5 hours; and / or The mass ratio of the reducing agent to the catalyst precursor supported on the active component is 0.3-1.

5.

5. The preparation method according to claim 3 or 4, characterized in that, The method for preparing the support comprising magnesium oxide and nickel oxide includes the following steps: (1) Mix the aqueous solution containing nickel salt and magnesium salt with the alkaline aqueous solution, filter, and obtain the carrier precursor; (2) The carrier precursor is calcined.

6. The preparation method according to claim 5, characterized in that, The nickel salt is selected from one or more of nickel nitrates, acetates, sulfates, or chlorides, preferably one or more of nickel nitrate hexahydrate, nickel acetate tetrahydrate, nickel chloride hexahydrate, nickel sulfate hexahydrate, and nickel ammonium sulfate hexahydrate; and / or The magnesium salt is selected from one or more of magnesium nitrates, acetates, sulfates, or chlorides, preferably one or more of magnesium nitrate hexahydrate, magnesium acetate tetrahydrate, magnesium chloride hexahydrate, and anhydrous magnesium sulfate; and / or The alkaline aqueous solution is selected from one or more of sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, potassium hydroxide aqueous solution, or barium hydroxide aqueous solution; and / or The mass ratio of nickel in the nickel salt to magnesium in the magnesium salt is 20:1-1:20; preferably 5:1-1:5; more preferably 2.5:1-1:2.5; even more preferably 1:1-1:2; and / or The concentration of the alkaline aqueous solution is 50-100 g / L.

7. The preparation method according to claim 5 or 6, characterized in that, The calcination temperature is 500-1000℃, and / or The roasting time is 5-15 hours.

8. The preparation method according to any one of claims 3-7, characterized in that, The step of loading the active component onto the support includes: mixing the support with an aqueous solution of a transition metal salt containing the active component; Preferably, the transition metal salt containing the active component is selected from one or more of transition metal nitrates, acetates, sulfates, or organic compounds containing transition metals, and is preferably one or more of platinum nitrate, platinum acetate, platinum sulfate, ruthenium chloride, ruthenium nitrate, ruthenium acetate, palladium nitrate dihydrate, palladium acetate, palladium chloride, palladium sulfate, or palladium acetylacetonate. Preferably, the mass ratio of the transition metal salt containing the active component to the support is 1:10-1:

25.

9. The application of the hydrogenation catalyst according to claim 1 or 2 or the hydrogenation catalyst prepared by any one of claims 3-8 in the catalytic hydrogenation reaction of 4-CBA.

10. The application according to claim 9, characterized in that, The hydrogenation reaction is carried out at a temperature of 200–250°C; and / or The hydrogenation reaction is carried out at a pressure of 10–15 bar; and / or The hydrogenation reaction takes 120–130 minutes.

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