CN111135857B - Preparation method and application of reduced catalyst - Google Patents

Abstract

The invention discloses a method for preparing a reduced catalyst, which comprises the following steps: (1) Weighing a certain amount of nickel nitrate and cobalt salt or copper salt or molybdate and dissolving in water to obtain a metal salt solution, adding HZSM-5 carrier into the metal salt solution to obtain a suspension; (2) place the suspension sample on a shaker at room temperature and immerse it for a period of time, and after taking it out, evaporate the water to dryness at a certain temperature to obtain a solid sample; (3) place the solid sample placed in a reactor, and reduced in a hydrogen atmosphere at 250-600°C for 1-10h to obtain a reduced catalyst; wherein, the molar ratio of Ni:M in the reduced catalyst is 1-10:1-5, and the active metal component NiO The total mass of M and MO is 10-50% of the total mass of carrier and metal oxide; M is metal Co, Mo or Cu. In the preparation method of the present invention, the reduced catalyst is directly prepared without calcination treatment in the preparation process, the preparation method is simple, and the catalyst activity is high. The catalyst is used in the catalytic hydrogenation reaction of furfural, which can effectively improve the conversion rate of furfural.

Description

Preparation method and use of reduced catalyst

Technical Field

The invention relates to the technical field of catalysts, in particular to a preparation method and application of a reduction catalyst. The catalyst is mainly used for catalytic hydrogenation of furfural.

Background Art

In recent decades, the rapid consumption of energy has caused a sharp decline in crude oil reserves. The increase in fuel demand worldwide and the increasing attention to climate issues caused by the use of fossil energy have forced researchers to accelerate the development of new energy. Biomass is a renewable resource with abundant reserves, sustainability, and carbon neutrality. The research on converting lignocellulosic resources in biomass into gasoline-like hydrocarbon fuels or fuel additives has received a lot of attention. Lignocellulosic biomass is very stable and difficult to directly convert into other products. It is usually converted into liquid products by rapid pyrolysis and solvent thermal liquefaction technology, referred to as bio-oil. Compared with fossil fuels, bio-oil has the disadvantages of high oxygen content, high viscosity, low calorific value, and unstable chemical properties. It needs to be further hydrogenated for better application. Bio-oil has a complex composition and it is difficult to directly carry out catalytic hydrogenation. In order to better understand the changes in bio-oil components during catalytic hydrogenation, this chapter selects furfural, a typical representative substance in bio-oil, as a model compound for research, aiming to lay a theoretical foundation for direct catalytic hydrogenation of bio-oil.

Furfural (C ₅ H ₄ O ₂ , α-furfural) is the main product of hemicellulose hydrolysis and is a rich biomass resource. Furfural can be used as a selective solvent. The quasi-aromatic properties of the furan ring can dissolve aromatic unsaturated compounds, while the neutral polarity of furfural can partially dissolve polar and non-polar substances. In recent years, the research on using furfural as a raw material to produce furfuryl alcohol, tetrahydrofurfuryl alcohol, 2-methylfuran, 2-methyltetrahydrofuran and other petroleum alternative energy sources has received great attention from researchers. Mariscal et al. summarized in detail the reaction conditions, catalysts and selectivity of the main products for producing fuels and high-value-added chemicals from furfural, and found that the catalysts that can better achieve the catalytic conversion of furfural to produce fuel additives are still mainly precious metals Ru, Pt and Pd. At present, the catalysts used for catalytic hydrodeoxygenation of bio-oil and its model compounds are still mainly sulfided and precious metal catalysts. Sulfided catalysts are suitable for catalytic hydrodesulfurization and deoxygenation of sulfur-containing petroleum raw materials, while for bio-oil that is almost sulfur-free, there are problems of rapid deactivation in water and product contamination caused by sulfur loss. Precious metal catalysts have high catalytic hydrogenation efficiency but are expensive, which limits their large-scale industrial application. These reasons have prompted researchers to turn their attention to the research and development of low-cost transition metal catalysts. Zhang et al. loaded Ni on γ-Al ₂ O ₃ and SiO ₂ -Al ₂ O ₃ carriers to prepare reduced catalysts for catalytic hydrogenation of furfural. The addition of SiO ₂ in the carrier increases the specific surface area and pore size of the catalyst, improves the dispersibility of metal Ni element and the mass transfer rate of reactants, thereby improving the activity of catalytic hydrodeoxygenation of furfural. The above studies also show that the properties of the carrier and the promoter significantly affect the catalytic activity of the reduced catalyst for bio-oil and its model compounds. However, for reduced transition metal catalysts, few scholars have paid attention to the systematic study of the synergistic effects between carriers and main catalysts and co-catalysts.

The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

Summary of the invention

The object of the present invention is to provide a method for preparing a reduction catalyst, thereby overcoming the disadvantages of the existing catalysts, such as high cost, low raw material conversion rate and low product selectivity in catalytic hydrogenation reactions.

Another object of the present invention is to provide a catalyst prepared by the method, which is used for catalytic hydrogenation of furfural to improve the raw material conversion rate and product selectivity.

To achieve the above object, the present invention provides a method for preparing a reduced catalyst, comprising the following steps:

(1) Weighing a certain amount of nickel nitrate and cobalt salt or copper salt or molybdate, dissolving them in water to obtain a metal salt solution, and adding the HZSM-5 carrier to the metal salt solution to obtain a suspension; Ni in the above raw materials is the main catalyst, and Co, Cu and Mo are co-catalysts;

(2) placing the suspension sample on a shaker at room temperature for a period of time, taking it out and evaporating the water at a certain temperature to obtain a solid sample;

(3) placing a solid sample in a reactor and reducing it in a hydrogen atmosphere at 250-600° C. for 1-10 h to obtain a reduced catalyst; wherein the molar ratio of Ni:M (co-catalyst) in the reduced catalyst is 1-10:1-5, and the total mass of the active metal components NiO and MO (co-catalyst oxide) is 10-50% of the total mass of the carrier and the metal oxide; and M is metal Co, Mo or Cu.

Preferably, in the above technical solution, the cobalt salt in step (1) is cobalt nitrate or cobalt sulfate, the copper salt is copper nitrate or copper sulfate, and the molybdate is ammonium molybdate.

Preferably, in the above technical solution, the immersion time on the shaking table in step (2) is 1-10 h; the evaporation is to completely evaporate the water in a 70-100° C. oil bath; and the flow rate of hydrogen in the hydrogen atmosphere in step (3) is 50-100 mL/min.

Preferably, in the above technical solution, the HZSM-5 carrier is prepared using NaOH, NaAlO ₂ , silica sol, water and a template as raw materials, wherein the template comprises CTAB and TPAOH, and the molar ratio of CTAB and TPAOH is 0-10:0-10.

Preferably, in the above technical solution, preparing the HZSM-5 carrier comprises the following steps:

(a) using NaOH, NaAlO ₂ , silica sol, water and a template as raw materials, mixing NaOH, NaAlO ₂ , a certain amount of the template and water to obtain a first solution; mixing the silica solution with water to obtain a second solution;

(b) adding the first solution dropwise to the second solution under vigorous stirring, stirring and reacting for 1-5 hours, then adding an acid solution to adjust the pH value of the gel to alkaline, and reacting for 1-5 hours, then placing the gel in a hydrothermal reactor to react for a period of time, filtering after crystallization to obtain a solid product, washing the solid product with water until the washing liquid is close to neutral, drying, and calcining the dried solid product to remove the template to obtain a Na-type molecular sieve;

(c) Mixing the Na molecular sieve and the NH ₄ NO ₃ solution, placing the mixture in an oil bath at 80-100° C., heating and stirring the mixture for 1-10 hours to obtain a white solid product, and then drying the mixture; this process is repeated multiple times;

(d) calcining the obtained solid product at 500-600° C. for 1-10 h to obtain an H-type molecular sieve, which is then granulated to obtain a HZSM-5 carrier.

Preferably, in the above technical solution, the acid solution added in step (b) is sulfuric acid, the temperature of the hydrothermal reaction is 150-200°C, and the crystallization time of the hydrothermal reaction is 30-60h; the solid product obtained after crystallization is a silica-alumina gel, and the molar ratio of the components _SiO2 : _{Al2O3 :} template: _Na2O : _H2O in the silica-alumina gel is 5-30:0.1-1:0.1-2:1-3:200-600.

Preferably, in the above technical solution, in step (b), the drying is performed at 90-120° C. for 8-20 h; and the calcination is performed at 500-600° C. for 1-10 h.

Preferably, in the above technical solution, in step (c), the process is repeated multiple times to mix the dried white product with NH ₄ NO ₃ solution for reaction, and the process is repeated 2-5 times.

The invention discloses an application of a reduced catalyst prepared by the above method, wherein the catalyst is used for the catalytic hydrogenation reaction of furfural.

Preferably, in the above technical solution, the waste furfural is subjected to a catalyst hydrogenation reaction, comprising the following steps:

(1) placing furfural, a solvent and a catalyst in a reaction kettle; the mass ratio of furfural, the solvent and the catalyst is 1-10:1-30:0.01-1; the solvent is ethanol or n-heptane;

(2) The air in the reactor was replaced with hydrogen several times, and 1.5-5.0 MPa of hydrogen was filled. The reaction temperature was adjusted to 150-250°C. After reacting for 1-5 hours, the reactor was cooled to room temperature and the product was collected.

Preferably, in the above technical solution, the reducing catalyst is recovered after the catalytic hydrogenation reaction, and is treated and regenerated after recovery. The treatment and regeneration method comprises the following steps: the recovered catalyst is soaked in isopropanol for a period of time, dried under a vacuum environment, and then the dried catalyst is placed on a fixed bed generator, and reacted in a water vapor and hydrogen atmosphere at 300-450°C for 1-10h; wherein the volume ratio of the flow rate of hydrogen and water vapor is 1-20:1-20.

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

(1) The method for preparing the reduced catalyst of the present invention directly prepares the reduced catalyst without calcination during the preparation process. The preparation method is simple and the prepared catalyst has high activity.

(2) The reduced catalyst of the present invention is used for the catalytic hydrogenation reaction of furfural, which can effectively improve the conversion rate of furfural.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is an XRD analysis diagram of catalysts HZ-1C-Mo, HZ-1C-Co and HZ-1C-Cu formed by different promoters;

FIG2 is a NH ₃ -TPD analysis diagram of catalysts with different metal promoters;

FIG3 is a H ₂ -TPR graph of catalysts with different metal promoters;

FIG4 is a graph showing the conversion and product selectivity of furfural hydrogenation catalyzed by HZ-xC-C and HZSM-C;

5 is a graph showing the conversion and product selectivity of furfural catalytic hydrogenation over HZ-xC-C and HZSM-C catalysts in n-heptane solvent;

FIG. 6 is a graph showing the effect of different reaction times on the conversion rate and product selectivity of furfural catalytic hydrogenation.

DETAILED DESCRIPTION

The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

Main experimental materials and reagents

The main raw materials and reagents used in the experiment are shown in Table 1.

Table 1 Experimental reagents

Example 1

A method for preparing a reduced catalyst comprises the following steps:

(1) Preparation of HZSM-5 carrier

(a) TPAOH is used as a microporous template and CTAB is used as a mesoporous template. The pore size and pore size distribution of the molecular sieve are controlled by adjusting the ratio of the template. NaOH, _NaAlO2 , silica sol, water and template are used as raw materials; 1.16 g NaOH and 1.31 g _NaAlO2 are weighed and mixed with a certain amount of template and 10 g water to form a first solution; 30 g silica sol is mixed with 15 g water to form a second solution.

(b) adding the first solution dropwise to the second solution under vigorous stirring for not less than 1 hour. After the addition is completed, stirring is continued for 2 hours. Sulfuric acid is added to adjust the pH value of the gel to 10 and react for 2 hours. The gel is then placed in a hydrothermal reactor with a 100 ml polytetrafluoroethylene interior, sealed and placed at a temperature of 180°C for 48 hours of crystallization. The solid product obtained after crystallization is a silica-alumina gel, in which the molar ratio of the components _SiO2 : _{Al2O3 :} template: _Na2O : _H2O in the silica-alumina gel is 20:0.4:1:1.5:400.

(c) The solid product obtained after crystallization is filtered, washed with deionized water until the washing liquid is nearly neutral, and dried at 105° C. for 12 h. Subsequently, the dried solid product is ground into fine powder and calcined in a muffle furnace at 550° C. for 6 h to remove the template, thereby obtaining a Na-type molecular sieve.

(d) The prepared Na-type molecular sieve was placed in a 250 mL flask, and a 1 mol/L NH ₄ NO ₃ solution of about 10 times the mass of the molecular sieve was added, and the flask was placed in a 90°C oil bath and heated with stirring for 5 h. The obtained white solid product was dried at 105°C, and this process was repeated three times; the process of repeating step (d) was that the dried white solid product was then added with NH ₄ NO ₃ solution for mixed reaction, and this was repeated three times;

(e) Grind the obtained solid product evenly and calcine it in a muffle furnace at 550°C for 6 hours to obtain H-type molecular sieve (HZ). The H-type molecular sieve is tableted, ground, and sieved, and particles with a particle size of 40-80 mesh are taken as molecular sieve carriers, namely HZSM-5 carriers. The H-type molecular sieves prepared using different templates are named: HZ-xC-S, C represents the macromolecular template CTAB, and x represents the ratio of CTAB in the two templates. The molar ratio of CTAB and TPAOH is 0-10:0-10.

(2) Preparation of reduced catalyst

(a) weighing a certain amount of nickel nitrate and cobalt nitrate or copper nitrate or ammonium molybdate, adding water to dissolve to obtain a metal salt solution, and then adding an appropriate amount of HZ-xC-S carrier to the metal salt solution to obtain a suspension;

(b) The obtained liquid suspension was placed in a shaker and shaken at room temperature for 5 h, and then the water was completely evaporated in an oil bath at 80° C. to obtain a solid sample;

(c) The solid sample is placed in a quartz tube reactor and reduced in a hydrogen atmosphere at 400°C for 4 hours. The flow rate of hydrogen in the hydrogen atmosphere is 75 mL/min, and a reduced catalyst is obtained after the reaction; wherein the molar ratio of Ni:M in the reduced catalyst is 7:3, and the total mass of the active metal components NiO and MO is 25% of the total mass of the carrier and the metal oxide; M is metal Co, Mo or Cu. The catalysts prepared from different carriers are named HZ-xC-C according to the different carriers. The catalysts obtained in this example are named HZ-xC-Cu, HZ-xC-Mo and HZ-xC-Co according to the different metal components.

Example 2

A method for preparing a reduced catalyst comprises the following steps:

(1) Preparation of HZSM-5 carrier

(a) TPAOH is used as a microporous template and CTAB is used as a mesoporous template. The pore size and pore size distribution of the molecular sieve are controlled by adjusting the ratio of the template. NaOH, _NaAlO2 , silica sol, water and the template are used as raw materials; a certain amount of NaOH and _NaAlO2 is mixed with a certain amount of the template and an appropriate amount of water to form a first solution; and the silica sol is mixed with an appropriate amount of water to form a second solution.

(b) adding the first solution dropwise to the second solution under vigorous stirring for not less than 1 hour. After the addition is completed, stirring is continued for 1 hour. Sulfuric acid is added to adjust the pH value of the gel to 11 and react for 1 hour. The gel is then placed in a hydrothermal reactor with a 100 ml polytetrafluoroethylene interior, sealed and placed at a temperature of 150°C for 60 hours of crystallization. The solid product obtained after crystallization is a silica-alumina gel, in which the molar ratio of the components _SiO2 : _{Al2O3 :} template: _Na2O : _H2O in the silica-alumina gel is 30:0.1:0.1:3:200.

(c) The solid product obtained after crystallization is filtered, washed with deionized water until the washing liquid is nearly neutral, and dried at 90° C. for 20 h. Subsequently, the dried solid product is ground into fine powder and calcined in a muffle furnace at 500° C. for 10 h to remove the template, thereby obtaining a Na-type molecular sieve.

(d) The prepared Na-type molecular sieve was placed in a 250 mL flask, and a 1 mol/L NH ₄ NO ₃ solution of about 10 times the mass of the molecular sieve was added, and the flask was placed in an 80°C oil bath and heated with stirring for 10 h. The obtained white solid product was dried at 105°C, and this process was repeated three times; the process of repeating step (d) was that the dried white solid product was then added with NH ₄ NO ₃ solution for mixed reaction, and this was repeated twice;

(e) Grind the obtained solid product evenly and calcine it in a muffle furnace at 500°C for 10 hours to obtain H-type molecular sieve (HZ). The H-type molecular sieve is tableted, ground, and sieved, and particles with a particle size of 40-80 mesh are taken as molecular sieve carriers, namely HZSM-5 carriers. The H-type molecular sieves prepared using different templates are named: HZ-xC-S, C represents the macromolecular template CTAB, and x represents the ratio of CTAB in the two templates. The molar ratio of CTAB and TPAOH is 0-10:0-10.

(2) Preparation of reduced catalyst

(a) weighing a certain amount of nickel nitrate and cobalt nitrate or copper nitrate or ammonium molybdate, adding water to dissolve to obtain a metal salt solution, and then adding an appropriate amount of HZ-xC-S carrier to the metal salt solution to obtain a suspension;

(b) The obtained liquid suspension was placed in a shaker and shaken at room temperature for 1 h, and then the water was completely evaporated in an oil bath at 100° C. to obtain a solid sample;

(c) The solid sample is placed in a quartz tube reactor and reduced in a hydrogen atmosphere at 250°C for 10 hours. The flow rate of hydrogen in the hydrogen atmosphere is 50 mL/min, and a reduced catalyst is obtained after the reaction; wherein the molar ratio of Ni:M in the reduced catalyst is 10:1, and the total mass of the active metal components NiO and MO is 10% of the total mass of the carrier and the metal oxide; M is metal Co, Mo or Cu. The catalysts prepared from different carriers are named HZ-xC-C according to the different carriers. The catalysts obtained in this example are named HZ-xC-Cu, HZ-xC-Mo and HZ-xC-Co according to the different metal components.

Example 3

A method for preparing a reduced catalyst comprises the following steps:

(1) Preparation of HZSM-5 carrier

(a) TPAOH is used as a microporous template and CTAB is used as a mesoporous template. The pore size and pore size distribution of the molecular sieve are controlled by adjusting the ratio of the template. NaOH, _NaAlO2 , silica sol, water and the template are used as raw materials; a certain amount of NaOH and _NaAlO2 is mixed with a certain amount of the template and an appropriate amount of water to form a first solution; and the silica sol is mixed with an appropriate amount of water to form a second solution.

(b) adding the first solution dropwise to the second solution under vigorous stirring for not less than 1 hour. After the addition is completed, stirring is continued for 5 hours. Sulfuric acid is added to adjust the pH value of the gel to 8 and react for 5 hours. The gel is then placed in a hydrothermal reactor with a 100 ml polytetrafluoroethylene liner, sealed and placed at a temperature of 200°C for 30 hours of crystallization. The solid product obtained after crystallization is a silica-alumina gel, in which the molar ratio of the components _SiO2 : _{Al2O3 :} template: _Na2O : _H2O in the silica-alumina gel is 5:1:2:1:600.

(c) The solid product obtained after crystallization is filtered, washed with deionized water until the washing liquid is nearly neutral, and dried at 120° C. for 8 h. Subsequently, the dried solid product is ground into fine powder and calcined in a muffle furnace at 600° C. for 1 h to remove the template, thereby obtaining a Na-type molecular sieve.

(d) The prepared Na-type molecular sieve was placed in a 250 mL flask, and a 1 mol/L NH ₄ NO ₃ solution of about 10 times the mass of the molecular sieve was added. The flask was placed in a 100° C. oil bath and heated with stirring for 1 h. The obtained white solid product was dried at 105° C. This process was repeated three times. The process of repeating step (d) was that the dried white solid product was then added with NH ₄ NO ₃ solution for mixed reaction, and this process was repeated 5 times.

(e) Grind the obtained solid product evenly and calcine it in a muffle furnace at 600°C for 1 hour to obtain H-type molecular sieve (HZ). The H-type molecular sieve is tableted, ground, and sieved, and particles with a particle size of 40-80 mesh are taken as molecular sieve carriers, namely HZSM-5 carriers. The H-type molecular sieves prepared using different templates are named: HZ-xC-S, C represents the macromolecular template CTAB, and x represents the ratio of CTAB in the two templates. The molar ratio of CTAB and TPAOH is 0-10:0-10.

(2) Preparation of reduced catalyst

(a) weighing a certain amount of nickel nitrate and cobalt nitrate or copper nitrate or ammonium molybdate, adding water to dissolve to obtain a metal salt solution, and then adding an appropriate amount of HZ-xC-S carrier to the metal salt solution to obtain a suspension;

(b) The obtained liquid suspension was placed in a shaker and shaken for 10 h at room temperature, and then the water was completely evaporated in an oil bath at 100° C. to obtain a solid sample;

(c) The solid sample is placed in a quartz tube reactor and reduced in a hydrogen atmosphere at 600°C for 1 hour. The flow rate of hydrogen in the hydrogen atmosphere is 50 mL/min. After the reaction, a reduced catalyst is obtained; wherein the molar ratio of Ni:M in the reduced catalyst is 1:5, and the total mass of the active metal components NiO and MO is 50% of the total mass of the carrier and the metal oxide; M is metal Co, Mo or Cu. The catalysts prepared from different carriers are named HZ-xC-C according to the different carriers. The catalysts obtained in this example are named HZ-xC-Cu, HZ-xC-Mo and HZ-xC-Co according to the different metal components.

Example 4

A method for preparing a reduced catalyst comprises the following steps:

(1) Preparation of HZSM-5 carrier

(a) TPAOH is used as a microporous template and CTAB is used as a mesoporous template. The pore size and pore size distribution of the molecular sieve are controlled by adjusting the ratio of the template. NaOH, _NaAlO2 , silica sol, water and the template are used as raw materials; a certain amount of NaOH and _NaAlO2 is mixed with a certain amount of the template and an appropriate amount of water to form a first solution; and the silica sol is mixed with an appropriate amount of water to form a second solution.

(b) adding the first solution dropwise to the second solution under vigorous stirring for not less than 1 hour. After the addition is completed, stirring is continued for 3 hours. Sulfuric acid is added to adjust the pH value of the gel to 9 and react for 2 hours. The gel is then placed in a hydrothermal reactor with a 100 ml polytetrafluoroethylene interior, sealed and placed at a temperature of 190°C for a crystallization time of 50 hours. After crystallization, the solid product obtained is a silica-alumina gel, in which the molar ratio of the components _SiO2 : _{Al2O3 :} template: _Na2O : _H2O in the silica-alumina gel is 15:0.5:1:2:500.

(c) The solid product obtained after crystallization is filtered, washed with deionized water until the washing liquid is nearly neutral, and dried at 100° C. for 14 h. Subsequently, the dried solid product is ground into fine powder and calcined in a muffle furnace at 550° C. for 4 h to remove the template, thereby obtaining a Na-type molecular sieve.

(d) The prepared Na-type molecular sieve was placed in a 250 mL flask, and a 1 mol/L NH ₄ NO ₃ solution of about 10 times the mass of the molecular sieve was added, and the flask was placed in a 90°C oil bath and heated with stirring for 4 h. The obtained white solid product was dried at 105°C, and this process was repeated three times; the process of repeating step (d) was that the dried white solid product was then added with NH ₄ NO ₃ solution for mixed reaction, and this was repeated three times;

(e) Grind the obtained solid product evenly and calcine it in a muffle furnace at 550°C for 5 hours to obtain H-type molecular sieve (HZ). The H-type molecular sieve is tableted, ground, and sieved, and particles with a particle size of 40-80 mesh are taken as molecular sieve carriers, namely HZSM-5 carriers. The H-type molecular sieves prepared using different templates are named: HZ-xC-S, C represents the macromolecular template CTAB, and x represents the ratio of CTAB in the two templates. The molar ratio of CTAB and TPAOH is 0-10:0-10.

(2) Preparation of reduced catalyst

(a) weighing a certain amount of nickel nitrate and cobalt nitrate or copper nitrate or ammonium molybdate, adding water to dissolve to obtain a metal salt solution, and then adding an appropriate amount of HZ-xC-S carrier to the metal salt solution to obtain a suspension;

(b) The obtained liquid suspension was placed in a shaker and shaken at room temperature for 5 h, and then the water was completely evaporated in an oil bath at 80° C. to obtain a solid sample;

(c) The solid sample is placed in a quartz tube reactor and reduced in a hydrogen atmosphere at 500°C for 6 hours. The flow rate of hydrogen in the hydrogen atmosphere is 70 mL/min, and a reduced catalyst is obtained after the reaction; wherein the molar ratio of Ni:M in the reduced catalyst is 5:2, and the total mass of the active metal components NiO and MO is 30% of the total mass of the carrier and the metal oxide; M is metal Co, Mo or Cu. The catalysts prepared from different carriers are named HZ-xC-C according to the different carriers. The catalysts obtained in this example are named HZ-xC-Cu, HZ-xC-Mo and HZ-xC-Co according to the different metal components.

The reduced catalyst prepared in Example 1-4 is used for the catalytic hydrogenation reaction of furfural. It comprises the following steps:

(1) placing furfural, a solvent and a catalyst in a reactor; the mass ratio of furfural, the solvent and the catalyst is 1-10:1-30:0.01-1, and the solvent is ethanol or n-heptane;

(2) replacing the air in the reactor with hydrogen multiple times, filling with 1.5-5 MPa of hydrogen, adjusting the reaction temperature to 150-210°C, and the rotation speed to 250-400 rpm; after reacting for 1-5 hours, cooling the reactor to room temperature and collecting the product; collecting the product includes collecting gaseous products and liquid products, and the liquid product and the catalyst are separated by filtration.

Catalyst regeneration

The reducing catalyst is recovered after the catalytic hydrogenation reaction, and then treated and regenerated. The treatment and regeneration method comprises the following steps: the recovered catalyst is soaked in isopropanol for a period of time, dried under a vacuum environment, and then the dried catalyst is placed on a fixed bed generator, and reacted in a water vapor and hydrogen atmosphere at 300-450° C. for 1-10 hours; wherein the volume ratio of the flow rate of hydrogen and water vapor is 1-20:1-20.

The reduced catalyst prepared in the above example was used to carry out a catalyst hydrogenation reaction on furfural in a 50 mL intermittent high-pressure reactor, which specifically includes the following steps:

(1) For each reaction, 2.0 g of furfural, 12 g of solvent (ethanol or n-heptane) and 0.05 g of catalyst were added to a reactor;

(2) The air in the reactor was replaced with hydrogen three times, and then filled with 1.5-5MPa of hydrogen, the reaction temperature was adjusted to 150-210°C, and the rotation speed was 250-400rpm; after reacting for 1-5h, the product was cooled to room temperature and collected. The gas product was analyzed using an offline gas phase, the liquid product and the catalyst were separated by filtration, the liquid product was analyzed using GC and GC-MS, and the catalyst was washed with ethanol several times, dried in a vacuum drying oven, and then collected.

Liquid product analysis is as follows:

The collected liquid products were qualitatively analyzed by GC-MS and retention index method, and the liquid products were quantitatively analyzed by GC-FID. The catalytic hydrogenation activity of the catalyst was evaluated by calculating the conversion rate (CON) of furfural, product selectivity (S) and carbon deposition rate (Y _coke ) of the catalyst. The calculation formulas of CON, S and Y _coke are as follows:

ω ₁ is the content of all products in the liquid product in GC analysis; ω ₂ is the content of furfural or guaiacol in the product; ω _x is the content of a certain component in the liquid product; m ₂ : the mass of the catalyst after the reaction; m ₁ : the mass of the catalyst before the reaction; m ₀ : the mass of the raw material.

Catalyst regeneration

The reducing catalyst is recovered after the catalytic hydrogenation reaction, and then treated and regenerated. The treatment and regeneration method includes the following steps: the recovered catalyst is soaked in 10 mL of isopropanol for 48 hours, and dried in a vacuum drying oven at 60° C. for 12 hours. Then the dried sample is placed on a fixed bed reactor and reacted in a water vapor and hydrogen atmosphere at 380° C. for 3 hours, and the volume ratio of hydrogen to water vapor flow rate is 10:1.

1. Characterization and analysis of the reduced catalyst prepared in Example 1

1. XRD analysis

XRD was measured using the SmartLab3 combined X-ray diffractometer from Agilent Technologies, USA. The measurement conditions were: Cu target, Kα ray source (λ=0.154nm), tube voltage and current were 40kV and 20mA respectively, scanning range was 5°-80°, and scanning speed was 5°/min. The test results are shown in Figure 1.

As shown in FIG1 , FIG1 shows the XRD analysis of catalysts HZ-1C-Mo, HZ-1C-Co and HZ-1C-Cu formed by different promoters. As shown in FIG1 , the diffraction peak intensities of metal Ni caused by the three metal promoters are different, indicating that the degree of Ni aggregation is different. The addition of promoter Cu is most likely to cause the formation of metal Ni single substance clusters, followed by promoter Mo, while the metal Ni single substance diffraction peak caused by promoter Co is the weakest. Possible reasons: The valence electron configuration of the metal promoter Cu is 3d ¹⁰ 4s ¹ , which is the metal that is most easily reduced to a single substance among the three metal promoters. The formation of copper single substance can provide electrons for the reduction of Ni ²⁺ , resulting in the easy reduction of the metal Ni component. At the same time, the acidity of the mesoporous carrier is weak, and the force on the metal component is weak, which is conducive to the aggregation of metal Ni single substance. No obvious diffraction peaks containing Co, Cu and Mo compounds were detected in the product, which may be due to the low metal content and good dispersibility of the promoter.

2. Texture property analysis

The texture property analysis was measured using a NOVA2200e chemical adsorption instrument from Quantachrome in a liquid nitrogen bath at 77K. Before the measurement, all samples were dried and degassed at 300°C in vacuum for 5 hours, and the adsorption and desorption points were collected in the relative pressure range of 0.01-0.97. The total specific surface area ( _SBET ) of the samples was evaluated using the Brunauer-Emmett-Teller (BET) method; the external surface area ( _Sext ) and micropore volume ( _Vmic ) of the samples were calculated using the t-plot method; the total pore volume ( _Vtotal ) of the samples was determined by the adsorption volume at P/ _P0 = 0.98; the mesopore volume ( _Vmeso ) was obtained by the difference between the total volume and the corresponding micropore volume. The experimental results are shown in Table 2.

Table 2 Structural properties of different supports and corresponding catalysts

As shown in Table 2, the textural properties of different promoters are shown in Table 2. Compared with the specific surface area and pore size of the HZ-1C-S carrier, the specific surface area of the catalyst containing the promoters Cu and Co increased by 39.8% and 42.0%, respectively, while the pore size decreased by 21.5% and 28.4%, respectively. The increase in specific surface area and the decrease in pore size were greater than those of HZ-1C-Mo. At the same time, a small amount of microporous structure appeared in the HZ-1C-Cu and HZ-1C-Co catalysts. After loading the metal active components, the pore size decreased and the specific surface area increased, which may be because: the metal microcrystalline particles formed during the loading and reduction process filled part of the mesoporous channels of the HZ-1C-S carrier, and at the same time, these microcrystalline particles may also aggregate with each other to form a new microporous structure. The ionic radius of the promoters Co and Cu is smaller than that of Mo, and they are easier to enter the pores of the carrier. The microcrystalline particles formed after reduction cause the catalyst pore size to decrease and the specific surface area to increase.

3. NH ₃ -TPD analysis

NH ₃ -TPD NH ₃ -TPD analysis of the support and catalyst was performed using a homemade quartz tube reactor equipped with a residual gas analyzer (RGA200). The specific steps are as follows: First, weigh 0.2g of the sample and dry and purge it in a 300℃ He gas flow for 2h; then cool the sample to 100℃, maintain 100℃ and pass NH ₃ flow for 1h, turn off NH ₃ and use He gas to purge the residual ammonia in the device until the NH ₃ signal detected online by the analyzer tends to be stable; finally, the ammonia adsorbed on the support or catalyst is desorbed using a programmed temperature increase, and the change of the NH ₃ signal after desorption is tracked and measured using RGA. The heating program is: keep at 50℃ for 2min, heat from 50℃ to 800℃, and the heating rate is 15℃/min. The precipitated ammonia is absorbed in two 50mL absorption bottles using 0.02mol/L HCl. The solution in the absorption bottle was titrated with 0.01 mol/L NaOH solution, and the methyl red-bromocresol green mixed solution was used as an indicator. The acid content (mmol/g) of the catalyst was calculated according to the volume of NaOH consumed. Figure 2 is the NH ₃ -TPD graph of different supports and catalysts, and the acid content and acidity distribution are shown in Table 3.

Table 3 Acidity and acidity distribution of different bimetallic catalysts

As shown in Table 3, compared with the HZ-1C-S carrier, the acid content of the catalyst decreases after metal loading, the medium acid content of the catalyst increases and the strong acid content decreases, indicating that the metal component is easy to combine with the strong acid site of the carrier, and the new acid site formed by the loading of the metal component belongs to the medium acid range. The additive Mo mainly causes the increase of weak acid sites, Cu mainly causes the increase of medium acid sites, and Co mainly causes the disappearance of strong acid sites. This shows that the additive Co is more likely to combine with the strong acid sites of the carrier.

As shown in Figure 2, Figure 2 shows the NH ₃ -TPD analysis results of different metal-promoted catalysts. As can be seen from Figure 2, there are significant differences in the NH ₃ desorption curves of the HZ-1C-S carrier and after loading different metal components. The original strong acid peaks above 400°C in the carrier obviously moved to the low temperature direction after loading the metal components, and the peak intensity between 200-400°C increased after loading the metal, indicating that the loading of the metal component reduces the strong acid active sites on the carrier surface on the one hand, and increases the medium acid active sites on the other hand.

4. H ₂ -TPR analysis

H ₂ -TPR is used to analyze the reduction degree of the metal active components of the catalyst and the interaction between the support and the metal active components. In this experiment, a homemade quartz tube reactor equipped with RGA200 was used to perform H ₂ -TPR analysis on the support and catalyst. First, 0.15 g of the sample was weighed and dried and purged in an Ar flow at 200°C for 2 hours; then the sample was cooled under Ar protection, and when the sample temperature dropped to 100°C, 15% H ₂ /Ar was used to purge the sample until the H ₂ and H ₂ O signals detected online by the analyzer tended to be stable; finally, the catalyst was reduced using a programmed temperature increase, and the changes in the H ₂ and H ₂ O signals during the reaction were detected online. The heating program was: 100°C for 2 minutes, heating from 100°C to 900°C, and the heating rate was 10°C/min.

The experimental results are shown in Figure 3. Figure 3 shows the _H2 -TPR graphs of HZ-1C-Cu, HZ-1C-Co and HZ-1C-Mo. As can be seen from the figure, compared with HZ-1C-Mo and HZ-1C-Cu samples, NiCo begins to show reduction peaks at lower temperatures, indicating that HZ-1C-Co has stronger reducibility. However, in the XRD analysis, the diffraction peak of the metal Ni single substance of the HZ-1C-Co catalyst is lower, which may be because the addition of metal Co promotes the dispersion of Ni metal atoms on the carrier, thereby improving the hydrogenation reducibility.

2. Experimental results and analysis of catalytic hydrogenation of furfural

1. Effect of catalyst pore size on the catalytic hydrogenation activity of furfural

The reaction of furfural catalytic hydrogenation over NiMo/HZSM-5 catalysts (HZ-xC-C) with different pore sizes was carried out at 180°C, a hydrogen pressure of 4MPa, and a reaction time of 3h. The obtained feedstock conversion rate and product selectivity are shown in Figure 4. For comparison, the reaction results of the commercial ZSM-5-supported catalyst HZSM-C are also listed in the figure. The experimental results show that the products of furfural catalytic hydrogenation over all catalysts are mainly furfuryl alcohol (FA), tetrahydrofurfuryl alcohol (THFA), 2-methylfuran (2-MF) and 2-methyltetrahydrofuran (2-MTHF), and there are also some other products, such as 3,4-dihydropyran, tetrahydropyran and 1,5-pentandiol (1,5-pentandiol). The liquid product with ethanol as the solvent also contains two main compounds, 2-ethoxymethylfuran (2-EOMF) and 2-ethoxymethyltetrahydrofuran (2-EOMTHF). Among them, FA, THFA, MF and 2-MTHF are important gasoline additive components. In the present invention, the total content (total) of gasoline additives in the hydrogenation product is also used as a performance indicator for evaluating the catalytic activity of the catalyst.

As shown in Figure 4, in the reaction with ethanol as the solvent, with the increase of the catalyst pore size, the conversion rate of furfural increases, the products are mainly 2-MTHF, THFA and FA, and the total content of the four main products increases, indicating that the macropores are conducive to the catalytic hydrogenation reaction of furfural. The increase in pore size is conducive to the rapid mass transfer of molecules and the utilization of internal active sites. In addition, with the increase of CTAB content, the acidity of the catalyst weakens and the reducibility of the Ni component in the catalyst increases. These factors lead to the continuous increase in the conversion rate of furfural and the hydrogenation activity of the product of the catalyst with a larger pore structure and weaker acidity. In addition, it was found that the commercial HZSM-C catalyzed furfural hydrogenation had a higher conversion rate, but the FA and 2-MF selectivity in the obtained products was higher, which may be related to its stronger acidity. The larger number of acidic sites in the HZSM-C catalyst is conducive to the adsorption of oxygen-containing functional groups in furfural and ethanol (solvent) molecules. Ethanol can directly provide active H atoms for the hydrogenation reaction of furfural, resulting in the conversion of furfural to produce furfuryl alcohol. At the same time, furfuryl alcohol and ethanol have similar polarities. Ethanol will inhibit the diffusion of furfuryl alcohol from the solution to the surface of the catalyst. The active sites on the catalyst surface will also be occupied by ethanol molecules in the solvent, which may prevent furfuryl alcohol from being adsorbed and hydrogenated and deoxygenated by the active sites, resulting in more furfuryl alcohol in the product.

The catalytic hydrogenation reaction of furfural was carried out using different solvents. Ethanol was used as the solvent as the experimental group, and n-heptane was used as the solvent as the comparative experiment. The experimental conditions were the same as those of ethanol as the solvent. The conversion rate and product selectivity of furfural catalytic hydrogenation in n-heptane with different catalysts are shown in Figure 5. Comparing Figures 4 and 5, whether ethanol or n-heptane is used as the solvent, the conversion rate of furfural, the selectivity of 2-methyltetrahydrofuran, furfuryl alcohol and tetrahydrofurfuryl alcohol all increased significantly with the increase of CTAB content. With the increase of CTAB content, the pore size of the catalyst increased (Table 2), the acidity weakened (Table 3), the reducibility of the Ni metal component increased (Figure 5), the diffusion and mass transfer rate of the reactant molecules accelerated, and the carbon deposition decreased. These factors caused the catalytic hydrogenation activity of the C=C unsaturated bond on the furan ring and the hydrogenation activity of the aldehyde group to increase, which ultimately led to a gradual increase in the conversion rate of furfural. In addition, in the catalytic hydrogenation product of the higher acidic catalyst (HZ-0C-C and HZSM-C), the content of 2-methylfuran is higher, while the content of 2-methyltetrahydrofuran and tetrahydrofurfuryl alcohol is lower, indicating that the catalytic effect of the higher acidic catalyst on furfural mainly occurs on the hydrodeoxygenation of the aldehyde group, rather than on the unsaturated double bond of the furan ring; on the contrary, in the catalytic hydrogenation product of the weaker acidic catalyst (HZ-0.5C-C, HZ-0.75C-C, HZ-1C-C), the content of 2-methylfuran is lower, while the content of 2-methyltetrahydrofuran and furfuryl alcohol is higher, indicating that the catalytic effect of the weaker acidic catalyst on furfural not only occurs on the unsaturated double bond of the benzene ring, but also occurs on the catalytic hydrogenation of the aldehyde group. The difference in product distribution caused by different catalysts is mainly attributed to the joint action of the acidic active site and the metal active site on the bifunctional catalyst.

As shown in Figures 4 and 5, compared with ethanol as a solvent, when n-heptane is used as a solvent, the raw material conversion rate and the total yield of gasoline additive components in the catalytic product of furfural are significantly improved, indicating that n-heptane is more conducive to the catalytic conversion of furfural to produce gasoline additive products. This may be because ethanol and furfural molecules are competitively adsorbed on the active sites of the catalyst, thereby inhibiting the conversion and hydrodeoxygenation reaction of furfural.

2. Effect of reaction temperature on the catalytic hydrogenation activity of furfural

The HZ-1C-Mo catalyst with high catalytic activity was selected for catalytic hydrogenation experiments to study the effect of reaction temperature on the catalytic hydrogenation activity of furfural. The experimental conditions were: reaction temperature 150℃-210℃, hydrogen pressure 4MPa, reaction time 3h, rotation speed 350rpm, and ethanol as the reaction solvent. The research results are shown in Table 4.

Table 4 Effect of reaction temperature on furfural catalytic hydrogenation conversion and product selectivity

As can be seen from Table 4, when the temperature increases from 150℃ to 180℃, the furfural conversion rate increases from 85.3% to 100%, indicating that increasing the reaction temperature is beneficial to the conversion of furfural. And with the increase of reaction temperature, the content of 2-methyltetrahydrofuran (2-MTHF) and tetrahydrofurfuryl alcohol (THFA) increases, the content of furfuryl alcohol decreases, and the degree of hydrogenation of the product gradually increases, indicating that higher temperature is conducive to the cracking of C-O bonds and the generation of active H atoms, thereby promoting the hydrogenation reaction; but as the temperature increases from 180℃ to 210℃, aliphatic hydrocarbons are produced in the hydrogenation product of furfural, resulting in a decrease in the total content of gasoline additive components. Therefore, the reaction temperature of 180℃ is most conducive to the conversion of furfural into gasoline additive products such as 2-MTHF and THFA. With the increase of reaction temperature, the reaction between the reaction solvent ethanol and furfural intensifies, producing more 2-ethoxymethyltetrahydrofuran (2-EOMTHF), which is also considered to be an important gasoline additive component.

3. Effect of reaction time on the catalytic hydrogenation activity of furfural

In order to explore the catalytic reaction path of furfural by reduced Ni-based catalyst, the effect of different reaction times on the catalytic hydrogenation reaction of furfural was investigated using HZ-1C-Mo catalyst. Experimental conditions: reaction temperature 180°C, hydrogen pressure 4MPa, rotation speed 350rpm, ethanol as reaction solvent. The results are shown in Figure 6.

As shown in Figure 6, with the increase of reaction time, the conversion rate of furfural increased from 75.5% to 100%, the contents of 2-methyltetrahydrofuran and tetrahydrofurfuryl alcohol gradually increased, while the total content of furfuryl alcohol and gasoline additives (2-MF, 2-MTHF, FA, THFA and 2-EOMTHF) first increased and then decreased, indicating that the increase in reaction time is beneficial to the conversion of furfural and furfuryl alcohol into 2-methyltetrahydrofuran and tetrahydrofurfuryl alcohol, but the products interact with the metal active sites for a longer time, resulting in an enhanced catalytic cracking reaction of the products, thereby causing a decrease in the total content of gasoline additives.

4. Effect of different metal additives on the catalytic hydrogenation activity of furfural

The results of the conversion rate and product selectivity of furfural catalytic hydrogenation by different metal promoter catalysts are shown in Table 5. The experimental conditions are: reaction temperature 180°C, hydrogen pressure 4MPa, reaction time 3h, rotation speed 350rpm, ethanol as reaction solvent. The results are shown in Table 5.

Table 5 Effects of different catalyst promoters on catalytic furfural hydrogenation conversion and product selectivity

As can be seen from Table 5, the conversion rate of furfural catalytic hydrogenation by different promoter catalysts is in the following order: HZ-1C-Mo>HZ-1C-Co>HZ-1C-Cu. As shown in Figures 1 and 2, the addition of promoter Cu causes a large amount of aggregation of Ni active sites and a decrease in the acidity of the catalyst, which is not conducive to the activation of the catalyst for H ₂ , thus resulting in a lower raw material conversion rate for HZ-1C-Cu. However, the Cu promoter catalyst obtained a higher FA selectivity (21.1%), which may be related to the higher C=O bond activation ability of the Cu metal active site. The addition of promoter Co increases the catalyst's activity for CO bond hydrogenation, accelerates the conversion of furfuryl alcohol to 2-methyltetrahydrofuran, and leads to an increase in the content of 2-methyltetrahydrofuran; the addition of promoter Mo properly regulates the dispersion of Ni metal active sites and improves the reducibility of the catalyst (Figure 2), and the Mo metal site itself is conducive to the addition of compound double bonds and the adsorption of oxygen-containing compounds, thus promoting the conversion of furfural and the improvement of the degree of catalytic hydrogenation.

5. Evaluation of the stability and regeneration of HZ-1C-C catalytic hydrogenation of furfural

In order to explore the stability of the reduced catalyst in the catalytic hydrogenation process of furfural, the present invention regenerates the catalyst HZ-1C-C after catalytic hydrogenation and deoxygenation of furfural to obtain a regenerated catalyst. The regenerated catalyst, the fresh catalyst and the used waste catalyst are respectively used for the catalytic hydrogenation reaction of furfural. The reaction conditions are: temperature 180°C, hydrogen pressure 4MPa, rotation speed 350rpm, and n-heptane as the reaction solvent. The comparison results of the obtained raw material conversion rate and product selectivity are shown in Table 6.

Table 6 Comparison of conversion rate and product selectivity of catalytic hydrogenation of furfural by fresh catalyst, regenerated catalyst and spent catalyst

As shown in Table 6, compared with the fresh HZ-1C-C catalyst, the conversion rate of furfural catalyzed by the spent catalyst and the regenerated catalyst decreased by 4.3% and 1.7%, respectively. The reason for the decrease in catalyst conversion efficiency may be that the carbon deposition generated during the reaction leads to a decrease in catalyst activity. In addition, it was found that the regeneration process improved the catalytic activity of the catalyst to a certain extent. However, high-temperature water vapor may cause the destruction of the pore structure of the catalyst, resulting in the inability of the regenerated catalyst activity to recover to the catalytic activity of the fresh catalyst. Compared with the product of the furfural hydrogenation reaction catalyzed by the fresh catalyst, the content of tetrahydrofurfuryl alcohol and 2-methyltetrahydrofuran in the catalytic products of the spent catalyst and the regenerated catalyst decreased, while the content of furfuryl alcohol and 2-methylfuran increased, indicating that the hydrogenation activity of the spent catalyst and the regenerated catalyst for the unsaturated double bonds on the furan ring is weakened. For catalysts with weaker acidity, carbon deposition may combine with the metal active sites of the catalyst, resulting in a weakened ability of the catalyst to activate hydrogen and transfer hydrogen, resulting in a decrease in catalytic hydrogenation activity.

The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims (9)

1. A method for preparing a reduced catalyst for catalytic hydrogenation of furfural, characterized in that it comprises the following steps: (1) Weigh a certain amount of nickel nitrate and cobalt salt or copper salt or molybdate, dissolve them in water to obtain a metal salt solution, and add the HZSM-5 carrier into the metal salt solution to obtain a suspension; (2) Place the suspension sample on a shaker at room temperature to soak and react for a period of time, then take it out and evaporate the water at a certain temperature to obtain a solid sample; (3) placing the solid sample in a reactor and reducing it in a hydrogen atmosphere at 250-600° C. for 1-10 hours to obtain a reduced catalyst; wherein the molar ratio of Ni: M in the reduced catalyst is 1-10:1-5, and the total mass of the active metal components NiO and MO is 10-50% of the total mass of the carrier and the metal oxide; and M is metal Co, Mo or Cu. 2. The method for preparing a reduced catalyst for catalytic hydrogenation of furfural according to claim 1, characterized in that the cobalt salt in step (1) is cobalt nitrate or cobalt sulfate, the copper salt is copper nitrate or copper sulfate, and the molybdate is ammonium molybdate. 3. The method for preparing a reduced catalyst for catalytic hydrogenation of furfural according to claim 1, characterized in that the immersion time on the shaking table in step (2) is 1-10 hours; the evaporation to dryness is to completely evaporate the water in an oil bath at 70-100°C; and the flow rate of hydrogen in the hydrogen atmosphere in step (3) is 50-100 mL/min. 4. The method for preparing a reduced catalyst for furfural catalytic hydrogenation reaction according to claim 1, characterized in that the HZSM-5 carrier is prepared using NaOH, _NaAlO2 , silica sol, water and a template as raw materials, the template comprises CTAB and TPAOH, and the molar ratio of CTAB and TPAOH is 0-10:0-10. 5. The method for preparing a reduced catalyst for furfural catalytic hydrogenation according to claim 4, characterized in that the preparation of the HZSM-5 carrier comprises the following steps: (a) using NaOH, NaAlO ₂ , silica sol, water and a template as raw materials, mixing NaOH, NaAlO ₂ , a certain amount of the template and water to obtain a first solution; mixing silica sol with water to obtain a second solution; (b) adding the first solution dropwise to the second solution under vigorous stirring, stirring and reacting for 1-5 hours, then adding an acid solution to adjust the pH value of the gel to alkaline, and reacting for 1-5 hours, then placing the gel in a hydrothermal reactor to react for a period of time, filtering to obtain a solid product after crystallization, washing the solid product with water until the washing liquid is close to neutral, drying, and calcining the dried solid product to remove the template to obtain a Na-type molecular sieve; (c) Mixing the Na molecular sieve and the NH ₄ NO ₃ solution, placing the mixture in an oil bath at 80-100°C, heating and stirring the mixture for 1-10 hours to obtain a white solid product, which is then dried; this process is repeated multiple times; (d) The obtained solid product is calcined at 500-600° C. for 1-10 h to obtain an H-type molecular sieve, which is then granulated to obtain a HZSM-5 carrier. 6. The method for preparing a reduced catalyst for catalytic hydrogenation of furfural according to claim 5, characterized in that the acid solution added in step (b) is sulfuric acid, the temperature of the hydrothermal reaction is 150-200°C, and the crystallization time of the hydrothermal reaction is 30-60h; the solid product obtained after crystallization is a silica-alumina gel, and the molar ratio of each component _SiO2 : _{Al2O3 :} template: _Na2O : _H2O in the silica-alumina gel is 5-30:0.1-1:0.1-2:1-3:200-600; the drying in step (b) is drying at 90-120°C for 8-20h; and the calcination is calcining at 500-600°C for 1-10h. 7. The method for preparing a reduced catalyst for catalytic hydrogenation of furfural according to claim 5, characterized in that the process in step (c) is repeated multiple times to mix the dried white product with _{NH4NO3 solution} for reaction, and the process is repeated 2-5 times. 8. Use of the reduced catalyst prepared by the method of claim 1, characterized in that the catalytic hydrogenation reaction of furfural comprises the following steps: (1) placing furfural, solvent and catalyst in a reaction kettle; the mass ratio of furfural, solvent and catalyst is 1-10:1-30:0.01-1; the solvent is ethanol or n-heptane; (2) The air in the reactor was replaced with hydrogen several times, and 1.5-5.0 MPa of hydrogen was filled in. The reaction temperature was adjusted to 150-250°C. After reacting for 1-5 hours, the reactor was cooled to room temperature and the product was collected. 9. The use according to claim 8, characterized in that the reduced catalyst is recovered after the catalytic hydrogenation reaction, and is treated and regenerated after recovery, and the treatment and regeneration method comprises the following steps: the recovered catalyst is soaked in isopropanol for a period of time, dried under a vacuum environment, and then the dried catalyst is placed on a fixed bed generator, and reacted in a water vapor and hydrogen atmosphere at 300-450°C for 1-10h; wherein the volume ratio of the flow rate of hydrogen and water vapor is 1-20:1-20.

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