Catalyst, catalyst preparation method and method for preparing long-chain butanediol by catalyzing saccharides through catalyst

Abstract

The invention discloses a catalyst, a preparation method of the catalyst and a method for preparing long-chain butanediol by catalyzing saccharides, and belongs to the technical field of chemical preparation of materials. The catalyst is prepared by loading a load PdCl2 on a carrier tungsten hexachloride, silicon dioxide or a molecular sieve, the catalyst can realize complete conversion of saccharides in an aqueous solution environment under relatively mild conditions, high-yield dihydric alcohol is obtained, and butanediol is a main product. The catalyst has the advantages of being excellent in cycle performance, stable in structure, green, environmentally friendly and the like, and a new conversion way is provided for converting carbohydrates into long-chain butanediol.

Description

Technical Field

[0001] The invention belongs to the technical field of preparing materials by chemical methods, and in particular relates to a catalyst, a method for preparing the catalyst, and a method for preparing long-chain butanediol by catalyzing sugars. Background Art

[0002] With the gradual depletion of fossil energy, in order to meet the huge needs of human life, the use of renewable energy to replace part of fossil energy has attracted people's attention. Among renewable energy sources, biomass has the characteristics of sustainable green carbon source, wide distribution, green environmental protection, etc., so it has aroused great research interest. Biomass has the most abundant content of cellulose and hemicellulose, so it is often used as a raw material for the preparation of high value-added platform chemical diols (ethylene glycol, propylene glycol, butanediol). Among them, butanediol is widely used in the fields of chemical industry, medicine, cosmetics, etc., and is a high-value and multifunctional platform chemical.

[0003] The main methods for industrial production of butanediol include the aldehyde-acetylene method, butane oxidation method, etc. However, the raw materials of these methods are mainly derived from petroleum conversion, and the reaction process will cause serious pollution to the environment. However, the preparation of butanediol by selective hydrogenolysis of biomass is considered to be a green and environmentally friendly method. At present, the research on the preparation of diols from biomass requires harsh reaction conditions, such as high temperature, high pressure, and long reaction time, and also has high requirements for the reaction equipment, which limits the preparation of diols from catalytic sugars, especially the preparation of a specific diol. Summary of the invention

[0004] In view of the above technical problems, the present invention provides a catalyst, a method for preparing the catalyst and a method for preparing long-chain butanediol by catalyzing sugars.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] One of the technical objectives of the present invention is to provide a catalyst, which is prepared by loading PdCl2 on a carrier; the loading amount of the carrier is 20-90wt%.

[0007] The present invention uses PdCl2 as a metal precursor. During the process of preparing the catalyst, palladium dichloride combines with a carrier to undergo a chemical reaction, thereby changing the chemical environment of the carrier and the metal precursor. The transfer of electrons between atoms will generate oxygen vacancies, and Lewis acid sites will also be generated during the process. It is the presence of these active sites that makes the catalyst catalytically active.

[0008] Furthermore, the carrier is tungsten hexachloride, silicon dioxide or molecular sieve.

[0009] The second technical purpose of the present invention is to provide a method for preparing a catalyst, which can be prepared in one of the following two ways, specifically comprising the following steps:

[0010] Method 1: PdCl2 and a carrier are dissolved in an organic solvent, the obtained mixed solution is transferred to a polytetrafluoroethylene liner for hydrothermal reaction, washed and dried, and the obtained solid powder is the catalyst;

[0011] Method 2: PdCl2 is dissolved in an organic solvent, and then the carrier is immersed in the obtained solution and subjected to a heating treatment. The obtained solid powder is subjected to a reduction reaction in a reducing atmosphere to obtain the catalyst.

[0012] Furthermore, in method 1,

[0013] The amount ratio of PdCl2, carrier and organic solvent is 0.13g:0.89g:25mL; and / or

[0014] The organic solvent is ethanol; and / or

[0015] The carrier is tungsten hexachloride; and / or

[0016] The parameters of the hydrothermal reaction are: temperature 160° C., time 24 h.

[0017] Furthermore, in method 2,

[0018] The amount ratio of PdCl2, carrier and organic solvent is 0.13g:0.89g:25mL; and / or

[0019] The organic solvent is ethanol; and / or

[0020] The carrier is silicon dioxide or molecular sieve; and / or

[0021] The specific steps of the heating treatment are: stirring in a 70°C water bath until the ethanol is completely volatilized; and / or

[0022] The parameters of the reduction reaction are: heating rate 3°C / min, temperature 200°C, time 4h, and reducing atmosphere of hydrogen.

[0023] The third technical purpose of the present invention is to provide an application of the catalyst in the preparation of long-chain butanediol.

[0024] The fourth technical purpose of the present invention is to provide a method for catalyzing sugars to prepare long-chain butanediol, comprising the following steps: adding sugars, solvents and the catalyst into a high-pressure reactor, and carrying out a conversion reaction under a protective atmosphere to obtain the long-chain butanediol.

[0025] The catalyst is used to promote the activation of hydrogen in the hydrogenation reaction, so that the double bonds and carbonyl groups in the reaction intermediates are hydrogenated and reduced, and finally the butanediol product is formed.

[0026] Furthermore, the mass ratio of the catalyst to the sugar is (1-15):10.

[0027] Further, the sugar comprises one of glucose, fructose, cellulose, starch and corn cob; and / or

[0028] The solvent is water.

[0029] Furthermore, the conditions of the conversion reaction are: temperature 110-200°C, time 1-15h, and protective gas pressure 0.1-3MPa.

[0030] Compared with the prior art, the present invention has the following advantages and technical effects:

[0031] (1) The catalyst used in the present invention is prepared by a "one-pot hot method", the preparation process is simple, and the environmental pollution is small;

[0032] (2) The present invention uses sugars obtained from biomass conversion as raw materials, thereby achieving the recycling of waste resources;

[0033] (3) The present invention uses the prepared catalyst to catalyze the conversion of sugars into butanediol. Under mild reaction conditions, sugars can be completely converted and a high yield of butanediol can be obtained. After multiple cycles of the catalyst, the yield of butanediol does not decrease significantly, and the catalyst maintains a good structure and has excellent recycling performance. The yield of butanediol can reach up to 53%;

[0034] (3) The present invention directly synthesizes the target product under relatively mild reaction conditions, and the whole process is short in process flow, easy to operate, and green and environmentally friendly. In an aqueous solution environment, the conversion of sugars to butanediol can be achieved, providing a new way for the production of butanediol. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 For Pd-WO in Application Example 1 x Reaction flow chart of the catalyst-catalyzed conversion of glucose into butanediol;

[0037] Figure 2 The original Pd-WO in Example 1 x Catalyst and recovery of Pd-WO x XRD patterns of the catalysts. DETAILED DESCRIPTION

[0038] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0039] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0040] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0041] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0042] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0043] The embodiment of the present invention discloses a catalyst, wherein a supported substance PdCl2 is supported on a support tungsten hexachloride (WCl6), silicon dioxide (SiO2) or molecular sieve (S-1) to prepare the catalyst, wherein the supported amount of the support is 20-90wt%, such as 22%, 45%, 63% or 86%. The catalyst can achieve complete conversion of sugars under relatively mild conditions in an aqueous solution environment, and obtain diols with high yields, wherein butanediol is the main product. The catalyst has the advantages of excellent cycle performance, stable structure, and green environmental protection, thereby providing a new conversion pathway for sugar conversion into long-chain butanediol.

[0044] In one embodiment of the present invention, the preparation method of the catalyst comprises the following specific steps:

[0045] PdCl2 and the carrier are dissolved in an organic solvent, and the resulting mixed solution is transferred to a polytetrafluoroethylene liner for hydrothermal reaction, washed, and dried to obtain a solid powder, which is the catalyst. (Method 1)

[0046] In another embodiment of the present invention, the preparation method of the catalyst comprises the following specific steps:

[0047] PdCl2 is dissolved in an organic solvent, and then the carrier is immersed in the obtained solution and subjected to a heating treatment. The obtained solid powder is subjected to a reduction reaction under a reducing atmosphere to obtain the catalyst (method 2).

[0048] In method 1, the usage ratio of PdCl2, carrier and organic solvent is 0.13g:0.89g:25mL; the organic solvent is ethanol; the carrier is tungsten hexachloride; the parameters of the hydrothermal reaction are: temperature 160°C, time 24h.

[0049] In method 2, the dosage ratio of PdCl2, carrier and organic solvent is 0.13g:0.89g:25mL; the organic solvent is ethanol; the carrier is silica or molecular sieve; the specific steps of the heating treatment are: stirring in a 70°C water bath until the ethanol is completely volatilized; the parameters of the reduction reaction are: heating rate 3°C / min, temperature 200°C, time 4h.

[0050] The above catalyst can be used to catalyze sugars to prepare long-chain butanediol, and the specific method includes the following steps:

[0051] Sugar, water and the catalyst are added into a high-pressure reactor, and a conversion reaction is carried out under a reducing atmosphere to obtain the long-chain butanediol.

[0052] In the following preferred embodiments of the present invention, the mass ratio of the catalyst to the sugar is (1-15): 10. Exemplarily, the mass ratio of the catalyst to the sugar in the following embodiments of the present invention is 1:10, 2.5:10, 5:10, 10:10, 15:10 or any value between the aforementioned ranges.

[0053] In the following preferred embodiments of the present invention, the sugar comprises one of glucose, fructose, cellulose, starch and corn cob.

[0054] In the following preferred embodiments of the present invention, the temperature of the conversion reaction is 110-200°C. Exemplarily, in the following embodiments of the present invention, the temperature of the conversion reaction is 140°C, 160°C, 180°C or any value within the aforementioned range.

[0055] In the following preferred embodiments of the present invention, the time of the conversion reaction is 1-15 h. Exemplarily, in the following embodiments of the present invention, the time of the conversion reaction is 1 h, 4 h, 8 h, 12 h or any value within the aforementioned range.

[0056] In the following preferred embodiments of the present invention, the protective gas pressure of the conversion reaction is 0.1-3 MPa. Exemplarily, in the following embodiments of the present invention, the protective gas pressure of the conversion reaction is 0.2 MPa, 0.6 MPa, 1 MPa, 2 MPa or any value within the aforementioned ranges.

[0057] In one embodiment of the present invention, the method for catalyzing sugars to prepare long-chain butanediol comprises the following steps:

[0058] Add 100 mg of sugar, (10-150) mg of catalyst and 10 mL of water into a container, seal the container, purge it with H2 for multiple times to remove the air in the container, fill the container with 0.6 MPa of H2, heat it to 110-200° C. at 500 rpm, react for 1-15 hours, wait for the reaction to end and cool, filter the supernatant through a 0.22 um pore size filter membrane, and then perform high performance liquid chromatography analysis, collect the solid by centrifugation to obtain butanediol.

[0059] The loading amount described in the present invention is the content ratio of the active ingredient (the sum of the active ingredient and the carrier content).

[0060] The raw materials used in the present invention are all purchased from the market.

[0061] The technical solution of the present invention is further illustrated by the following embodiments.

[0062] Example 1

[0063] A method for preparing a catalyst comprises the following steps:

[0064] 0.13 g of PdCl2 and 0.89 g of tungsten hexachloride (WCl6) were mixed and dissolved in 25 mL of ethanol to obtain a mixed solution, which was transferred to a tetrafluoroethylene-lined reactor and reacted at 160 °C for 24 h, washed, and then vacuum dried at 60 °C overnight to obtain a catalyst, which was recorded as Pd-WO x .

[0065] The WCl6 loading is 86%.

[0066] Example 2

[0067] A method for preparing a catalyst comprises the following steps:

[0068] 0.13 g of PdCl2 was dissolved in 25 mL of ethanol, and then 0.89 g of silicon dioxide (SiO2) was immersed in the resulting solution and stirred in a 70°C water bath until the ethanol was completely evaporated. The solid powder was then placed in a tubular furnace and reduced for 4 hours in a hydrogen atmosphere at a reduction temperature of 200°C and a heating rate of 3°C / min to prepare a catalyst, recorded as Pd / SiO2.

[0069] Example 3

[0070] A method for preparing a catalyst comprises the following steps:

[0071] 0.13 g of PdCl2 was dissolved in 25 mL of ethanol, and then 0.89 g of molecular sieve (S-1) was immersed in the resulting solution and stirred in a 70°C water bath until the ethanol was completely evaporated. Subsequently, the solid powder was placed in a tubular furnace and reduced for 4 hours in a hydrogen atmosphere at a reduction temperature of 200°C and a heating rate of 3°C / min to prepare a catalyst, which was recorded as Pd / S-1.

[0072] Example 4

[0073] Same as Example 1, except that the mass of tungsten hexachloride (WCl6) is 0.15 g, that is, the WCl6 loading is 22%, and the obtained catalyst is recorded as Pd-WO x -1.

[0074] Example 5

[0075] Same as Example 1, except that the mass of tungsten hexachloride (WCl6) is 0.3 g, that is, the WCl6 loading is 45%, and the obtained catalyst is recorded as Pd-WO x -2.

[0076] Example 6

[0077] Same as Example 1, except that the mass of tungsten hexachloride (WCl6) is 0.6 g, that is, the WCl6 loading is 63%, and the obtained catalyst is recorded as Pd-WO x -3.

[0078] Application Example 1

[0079] 50 mg of Pd-WO prepared in Example 1 was added into the autoclave. xCatalyst, 100 mg of sugar (glucose, fructose, starch, corn cob, cellulose) and 10 mL of water were added, and then the reactor was sealed and flushed with H2 for several times to remove the air in the reactor. The reactor filled with 0.6 MPa of H2 was then heated to 160°C and stirred at 500 revolutions per minute for 8 hours. After the reaction was completed, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of producing butanediol when different sugars were used as substrates are shown in Table 1.

[0080] Table 1 Reaction performance results of diols produced when different sugars are used as substrates

[0081] Substrate Substrate conversion rate / % Butanediol yield / % glucose 100 53 fructose 100 15 starch 67 32 Corn cob 43 28 Cellulose 51 8

[0082] It can be seen from the data in Table 1 that the Pd-WO synthesized by the simple hydrothermal method in the present invention x The catalyst catalyzes the reaction of sugars, and the process is simple. Butanediol can be prepared with high selectivity. At a relatively mild reaction temperature and a low hydrogen pressure, Pd-WO x The catalyst can catalyze the basic complete conversion of sugars, and can also partially convert sugars with more complex structures such as corn cobs and cellulose into butanediol. It can also be seen that when glucose and fructose are used as substrates, the substrate conversion rate can reach 100%, but in comparison, the yield of butanediol is better when glucose is used as a substrate, which can reach 53%. Compared with starch and corn cobs, the yield of fructose converted into butanediol is lower. The reason is that in the process of fructose being converted into butanediol, fructose first needs to be isomerized into glucose and further converted into butanediol. The catalyst of the present invention has low isomerization ability, so the yield of fructose converted into butanediol is low. Starch, corn cobs and cellulose first need to be hydrolyzed into glucose monomers before they can be further converted. The content of lignin in corn cobs is also very high, and the difficulty of hydrolysis is high. Therefore, the conversion rate of the three is low. This shows that it is better to use glucose as a substrate.

[0083] Application Example 2

[0084] 10 mg, 25 mg, 50 mg, 100 mg and 150 mg of Pd-WO prepared in Example 1 were added to the autoclave respectively. x Catalyst, 100 mg of sugar (glucose) and 10 mL of water were added, and the reactor was then sealed and flushed with H2 for several times to remove the air in the reactor. The reactor filled with 0.6 MPa of H2 was then heated to 160°C and stirred at 500 revolutions per minute for 8 hours. After the reaction was completed, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of glucose to butanediol at different catalyst dosages are shown in Table 2.

[0085] Table 2 Reaction performance results of glucose to diols at different catalyst dosages

[0086]

[0087]

[0088] As can be seen from Table 2, when the catalyst addition amount is 50 mg, the conversion rate of glucose can reach 100%, and the yield of butanediol can reach up to 53%. As the amount of catalyst increases, the yield of butanediol decreases, which may be due to the sintering of the catalyst, resulting in reduced activity. This shows that the performance is optimal when the catalyst addition amount is 50 mg.

[0089] Application Example 3

[0090] 50 mg of Pd-WO prepared in Example 1 was added into the autoclave. x Catalyst, 100 mg of sugar (glucose) and 10 mL of water were added, and the reactor was then sealed and flushed with H2 for several times to remove the air in the reactor. The reactor filled with 0.6 MPa of H2 was then heated to 140°C, 160°C and 180°C, respectively, and stirred at 500 revolutions per minute for 8 hours. After the reaction was completed, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of glucose to butanediol at different reaction temperatures are shown in Table 3.

[0091] Table 3 Reaction performance results of glucose to diols at different reaction temperatures

[0092] Reaction temperature / ℃ Substrate conversion rate / % Butanediol yield / % 140 65 20 160 100 53 180 100 50

[0093] As can be seen from Table 3, when the reaction temperature is lower than 160°C, the conversion rate of glucose cannot reach 100%, while when the reaction temperature reaches 160°C or above, glucose can still be 100% converted, but the yield of butanediol is reduced. This may be because the intermediates or butanediol generated under high temperature conditions are further degraded, resulting in a decrease in the yield of butanediol. This shows that the optimal reaction temperature is 160°C.

[0094] Application Example 4

[0095] 50 mg of Pd-WO prepared in Example 1 was added into the autoclave. xCatalyst, 100 mg of sugar (glucose) and 10 mL of water were added, and the reactor was then sealed and flushed with H2 for several times to remove the air in the reactor. The reactor filled with 0.6 MPa of H2 was then heated to 160°C and stirred at 500 rpm for 1 h, 4 h, 8 h and 12 h, respectively. After the reaction was completed, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of glucose to butanediol at different reaction times are shown in Table 4.

[0096] Table 4 Reaction performance results of glucose to diols at different reaction times

[0097] Reaction time / h Substrate conversion rate / % Butanediol yield / % 1 63 20 4 92 44 8 100 53 12 100 52

[0098] As can be seen from Table 4, when the reaction time is too short, the conversion rate of the substrate is too low. When the reaction time reaches 8h or more, the conversion rate of the substrate can reach 100%. As the reaction time increases, the yield of butanediol does not increase. The reason is that the amount of butanediol intermediates formed during the glucose conversion process is limited and has been completely converted within 8h. This shows that the optimal reaction time is 8h.

[0099] Application Example 5

[0100] 50 mg of Pd-WO prepared in Example 1 was added into the autoclave. x Catalyst, 100 mg sugar (glucose) and 10 mL water were added, and the reactor was then sealed and flushed with H2 for several times to remove the air in the reactor. The reactors filled with 0.2 MPa, 0.6 MPa, 1 MPa and 2 MPa of H2 were then heated to 160°C and stirred at 500 rpm for 8 h. After the reaction, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of glucose to butanediol at different reaction hydrogen pressures are shown in Table 5.

[0101] Table 5 Reaction performance results of glucose to diols at different reaction hydrogen pressures

[0102]

[0103]

[0104] It can be seen from Table 5 that the conversion rate of the substrate can only reach 100% when the hydrogen pressure reaches 0.6MPa or above during the reaction. As the pressure increases, the selectivity of the secondary reaction increases, thereby reducing the amount of the main product. In addition, as the hydrogen pressure increases, carbon deposition on the catalyst surface is easy, resulting in catalyst deactivation, which in turn affects the formation of the product. This shows that the best hydrogen pressure is 0.6MPa.

[0105] From Table 1 and Table 2, we can see that Pd-WO x It can effectively convert glucose into butanediol, and the main product is butanediol; Pd-WO x It is universally applicable in the binary process of preparing various sugars.

[0106] Application Example 6

[0107] The Pd-WO collected by centrifugation in Application Example 1 x The catalyst was subjected to a catalytic cycle experiment according to the method in Application Example 1, with glucose as the substrate. The reaction performance results of the recovered catalyst in catalyzing glucose to butanediol are shown in Table 6.

[0108] Table 6 Pd-WO in Example 1 x The reaction performance results of glucose to butanediol after multiple catalyst recycling

[0109] Cycle times Substrate conversion rate / % Butanediol yield / % 1 100 53 2 100 53 3 100 52 4 100 51 5 100 50

[0110] Figure 2 The original Pd-WO prepared in 1 x Catalyst and recovery of Pd-WO x From the XRD diagram of the catalyst, it can be seen that the recovered Pd-WO x (Recycled-Pd-WO x ) and the XRD peak pattern of the original Pd-WO x (Fresh-Pd-WO x ) have the same XRD peak shape.

[0111] From Table 6 and Figure 2 It can be seen that the Pd-WO prepared by Example 1 of the present invention x After the catalyst is recycled many times, the catalytic efficiency does not decrease significantly, and the recycled catalyst retains its intact crystal structure, with the advantages of being able to be recycled many times and being resistant to high temperatures.

[0112] Application Example 7

[0113] Into the autoclave were added 50 mg of the catalyst prepared in Examples 1 and 4-6, 100 mg of sugar (glucose) and 10 mL of water, respectively. The reactor was then sealed and flushed with H2 for several times to remove the air in the reactor. The reactor filled with 0.6 MPa of H2 was then heated to 160°C and stirred at 500 rpm for 8 h. After the reaction was completed, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of different catalysts for producing butanediol are shown in Table 7.

[0114] Table 7 Yield of butanediol produced by different catalysts

[0115] catalyst Substrate conversion rate / % Butanediol yield / % Pd-WOx 100 53 <![CDATA[Pd-WO x -1]]> 100 29 <![CDATA[Pd-WO x -2]]> 100 37 <![CDATA[Pd-WO x -3]]> 100 45

[0116] It can be seen from Table 7 that the loading amount of WCl6 will affect the yield of butanediol. With the increase of WCl6 loading amount, the yield of butanediol gradually increases. This is because at a lower loading amount, the retro-aldol condensation ability of glucose is weak, and the number of intermediates formed is small, resulting in a low yield of butanediol. In addition, glucose will be hydrogenated into by-products such as sorbitol. With the increase of loading amount, the bond breaking ability of glucose is enhanced, so the yield of butanediol increases.

[0117] Application Example 8

[0118] 50 mg of the catalyst prepared in Example 2 and Example 3, 100 mg of sugar (glucose) and 10 mL of water were added to the autoclave respectively, and then the reactor was sealed and flushed with H2 for several times to remove the air in the reactor. Then the reactor filled with 0.6 MPa of H2 was heated to 160°C and stirred at 500 revolutions per minute for 8 hours. After the reaction was completed, the solid catalyst was collected by centrifugation, and the supernatant was passed through a filter with a pore size of 0.22 μm and then analyzed by high performance liquid chromatography. The reaction performance results of different catalysts for producing butanediol are shown in Table 7.

[0119] Table 8 Reaction performance results of different catalysts to produce butanediol

[0120] catalyst Substrate conversion rate / % Butanediol yield / % <![CDATA[Pd / SiO2]]> 63 22 Pd / S-1 84 33

[0121] It can be seen from the data in Table 8 and Table 1 that, compared with the catalyst synthesized by the in-situ hydrothermal method in Example 1 of the present invention, the catalyst prepared by the in-situ hydrothermal method has better performance than the catalyst prepared by the impregnation method.

[0122] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A catalyst, characterized in that The prepared product is prepared by loading PdCl2 on a carrier; the loading amount of the carrier is 20-90wt%.

2. The catalyst according to claim 1, characterized in that The carrier is tungsten hexachloride, silicon dioxide or molecular sieve.

3. A method for preparing a catalyst as claimed in any one of claims 1 to 2, characterized in that: The preparation method adopts any one of the following two methods, and specifically comprises the following steps: Method 1: PdCl2 and a carrier are dissolved in an organic solvent, the obtained mixed solution is transferred to a polytetrafluoroethylene liner for hydrothermal reaction, washed and dried, and the obtained solid powder is the catalyst; Method 2: PdCl2 is dissolved in an organic solvent, and then the carrier is immersed in the obtained solution and subjected to a heating treatment. The obtained solid powder is subjected to a reduction reaction in a reducing atmosphere to obtain the catalyst.

4. The preparation method according to claim 3, characterized in that: In method one, The amount ratio of PdCl2, carrier and organic solvent is 0.13g:0.89g:25mL; and / or The organic solvent is ethanol; and / or The carrier is tungsten hexachloride; and / or The conditions of the hydrothermal reaction are: temperature 160° C., time 24 h.

5. The preparation method according to claim 3, characterized in that: In method 2, The amount ratio of PdCl2, carrier and organic solvent is 0.13g:0.89g:25mL; and / or The organic solvent is ethanol; and / or The carrier is silicon dioxide or molecular sieve; and / or The specific steps of the heating treatment are: stirring in a 70°C water bath until the ethanol is completely volatilized; and / or The reduction reaction conditions are: heating rate 3°C / min, temperature 200°C, time 4h, and reducing atmosphere of hydrogen.

6. Use of the catalyst according to any one of claims 1 to 2 in catalyzing the preparation of long-chain butanediol from sugars.

7. A method for catalyzing sugars to prepare long-chain butanediol, characterized in that: The following steps are involved: Add sugars, solvents and the catalyst according to any one of claims 1 to 2 into a high-pressure reactor, and carry out a conversion reaction under a protective atmosphere to obtain the long-chain butanediol.

8. The method for preparing long-chain butanediol by catalyzing sugars according to claim 7, characterized in that: The mass ratio of the catalyst to the sugar is (1-15):

10.

9. The method for preparing long-chain butanediol by catalyzing sugars according to claim 7, characterized in that: The sugar comprises one of glucose, fructose, cellulose, starch and corn cob; and / or The solvent is water.

10. The method for preparing long-chain butanediol by catalyzing sugars according to claim 7, characterized in that: The conditions of the conversion reaction are: temperature 110-200° C., time 1-15 h, and protective gas pressure 0.1-3 MPa.

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