Catalyst for synthesizing 1, 4-cyclohexanedimethanol, preparation method and application

Abstract

The invention provides a catalyst for synthesizing 1, 4-cyclohexanedimethanol as well as a preparation method and application thereof, and the preparation method comprises the following steps: dissolving soluble zinc salt, calcium salt, copper salt, nickel salt, magnesium salt and assistant salt in deionized water to obtain a mixed solution; adding a certain amount of alkaline precipitant into the mixed solution, adding silicide after a certain time, and heating in an oil bath at 80-140 DEG C for 1-8 hours to obtain a first sticky material; and centrifuging the first sticky material, washing, drying, roasting at 300-800 DEG C for 4-8 hours to obtain the catalyst, and sequentially tabletting, crushing and screening the catalyst. According to the catalyst prepared by a novel deposition method, on the basis of ensuring excellent and stable performance of the catalyst, better catalytic performance can be obtained at lower pressure and temperature, and the cost and danger of industrial production are reduced.

Description

Technical Field

[0001] The present application relates to the field of catalyst preparation, and in particular to a catalyst for synthesizing 1,4-cyclohexanedimethanol, a preparation method and an application thereof. Background Art

[0002] 1,4-cyclohexanedimethanol (CHDM) is an important raw material for polyester synthesis, such as polyethylene terephthalate (PCT), polyethylene terephthalate glycol cyclohexanedimethanol (PETG / PCTG), copolyester PCTA, etc. In addition, it is also widely used in industries such as polyester for coatings, unsaturated polyester resins and polyurethanes.

[0003] At present, the industrial production process of 1,4-cyclohexanedimethanol is to use dimethyl terephthalate as raw material and obtain it through two-step hydrogenation. The catalyst preparation process is relatively complicated, there are many by-products that are not easy to separate and purify, a lot of wastewater is generated, and impurities are easily introduced into the catalyst. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems in the related art to a certain extent. The present application uses a novel deposition method to synthesize a catalyst for preparing 1,4-cyclohexanedimethanol by hydrogenation of dimethyl 1,4-cyclohexanedicarboxylate. The process is simple and easy to operate, and impurities are not easily introduced. The obtained catalyst has high activity and selectivity under mild reaction conditions, and has strong stability in long-term operation.

[0005] According to an embodiment of the first aspect of the present application, a method for preparing a catalyst for synthesizing 1,4-cyclohexanedimethanol is proposed, comprising the following steps:

[0006] Dissolving at least one of soluble zinc salt, calcium salt, copper salt, nickel salt, and magnesium salt and an auxiliary salt in deionized water to obtain a mixed solution;

[0007] Adding a quantitative amount of alkaline precipitant to the mixed solution to form a precipitate;

[0008] After adding a certain amount of silicide to the mixed precipitate, heating in an oil bath at 80-140° C. for 1-8 hours obtains a first viscous material;

[0009] The first viscous material is aged, centrifuged, washed, and then dried to obtain a second viscous material, and then calcined at 300-800° C. for 4-8 hours to obtain a catalyst, and the catalyst is successively tableted, crushed, and sieved.

[0010] In some embodiments, the zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc nitrate and zinc chloride;

[0011] And / or, the calcium salt is selected from at least one of calcium sulfate, calcium acetate, calcium nitrate and calcium chloride;

[0012] And / or, the copper salt is selected from at least one of copper sulfate, copper acetate, copper nitrate and copper chloride;

[0013] And / or, the nickel salt is selected from at least one of nickel sulfate, nickel acetate, nickel nitrate and nickel chloride;

[0014] And / or, the magnesium salt is selected from at least one of magnesium sulfate, magnesium acetate, magnesium nitrate and magnesium chloride;

[0015] And / or, the auxiliary salt is at least one of metal nitrate, metal sulfate, metal acetate and metal chloride; the metal element includes Au element, Pt element, Pd element, Ag element, Ru element, Mn element, Ti element, Re element or Ce element.

[0016] In some embodiments, the molar ratio of the zinc salt to the total amount of the calcium salt, the copper salt, the nickel salt, the magnesium salt and the auxiliary salt is 0.1-10.

[0017] In some embodiments, the alkaline precipitant includes one of ammonia water, sodium bicarbonate, sodium hydroxide, etc.;

[0018] In some embodiments, the pH of the mixed solution is in the range of 8-12, and the pH value is adjusted by an alkaline precipitant.

[0019] In some embodiments, the silicide includes at least one of silicon tetrachloride, methyl orthosilicate, ethyl orthosilicate, silica sol, or sodium silicate;

[0020] and / or, the silicide is SiO 2 According to the mass measurement, the mass ratio of the silicide to the mixed solution is 1-50.

[0021] In some embodiments, the pH range of the second adhesive is 7.5-8.

[0022] According to the second aspect of the present application, a catalyst for synthesizing 1,4-cyclohexanedimethanol is provided, which is obtained by the preparation method described in any of the above embodiments, wherein the catalyst is SiO 2 As a carrier, zinc, calcium, copper, nickel and magnesium are used as active ingredients, and the metal M in the auxiliary salt is used as an auxiliary agent; wherein the mass fraction of the total amount of zinc, calcium, copper, nickel and magnesium is 3-60% based on the catalyst, the mass fraction of the metal M is 0.1-20%, and the rest is SiO 2 .

[0023] According to the third aspect of the present application, the catalyst described in any of the above embodiments is used in the hydrogenation of dimethyl 1,4-cyclohexanedicarboxylate to prepare 1,4-cyclohexanedimethanol, wherein the catalyst is loaded into a fixed bed micro-reactor and reduced with a reducing gas, and the reduction parameters are: the gas flow rate is 20-1800h -1 , pressure is 1-6MPa, temperature is 200-800℃, time is 0.5-24h, and heating rate is 1-15℃ / min.

[0024] In some embodiments, the reducing gas is hydrogen or an inert gas containing hydrogen; in the inert gas containing hydrogen, the volume fraction of hydrogen is 1-100%.

[0025] According to the fourth aspect of the present application, the catalyst described in any of the above embodiments is used in the preparation of 1,4-cyclohexanedimethanol from a methanol solution of dimethyl 1,4-cyclohexanedicarboxylate, with hydrogen and a methanol solution of dimethyl 1,4-cyclohexanedicarboxylate as raw materials, and the reaction parameters are controlled as follows: the reaction pressure is 1-10 MPa, the reaction temperature is 180-400°C, the mass fraction of the methanol solution of dimethyl 1,4-cyclohexanedicarboxylate is 3-80%, and the raw material liquid hourly space velocity is 0.1-5h -1 , the hydrogen ester molar ratio is 50-400.

[0026] Compared with the related art, this application has the following technical effects:

[0027] 1. Excellent catalytic performance: The catalyst prepared by a new deposition method is SiO 2 As the carrier, zinc, calcium, copper, nickel and magnesium are the main active substances. The metal particles in the catalyst are highly dispersed and have strong interactions with the carrier, which helps to improve the stability of the catalyst and enhance the catalytic performance.

[0028] 2. The addition of other metal additives through additive salts can effectively improve the reaction efficiency of hydrogenating dimethyl 1,4-cyclohexanedicarboxylate to produce 1,4-cyclohexanedimethanol, and the catalyst exhibits excellent stability.

[0029] 3. The catalyst preparation process provided by the present invention is relatively efficient and can be mass-produced, and the performance of the catalyst can be optimized by adjusting the process parameters during the preparation process.

[0030] 4. Wide range of applications: The catalyst prepared by this method is suitable for the hydrogenation reaction of dimethyl 1,4-cyclohexanedicarboxylate, can maintain stable catalytic performance under different reaction conditions, and can meet production needs under different conditions.

[0031] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0033] Figure 1 It is a flow chart of the preparation method of the catalyst for synthesizing 1,4-cyclohexanedimethanol provided in one embodiment of the present application. DETAILED DESCRIPTION

[0034] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be construed as limiting the present application. On the contrary, the present application includes all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0035] "Scope" disclosed in the present application is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can be all expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0036] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0037] At present, the industrial production process of 1,4-cyclohexanedimethanol is to use dimethyl terephthalate as raw material and then undergo two-step hydrogenation. Some related technologies disclose the process of preparing 1,4-cyclohexanedimethanol by two-step hydrogenation of dimethyl terephthalate. The reaction is carried out in a fixed bed micro-reactor. The first step is to use Ru / Al 2 O 3 As a catalyst, dimethyl terephthalate was hydrogenated at a temperature of 140°C and a pressure of 4MPa. In the second step, modified Cu-Cr was used as a catalyst, the reaction temperature was 180°C, the pressure was 5MPa, and the yield of 1,4-cyclohexanedimethanol reached 94.3%. In order to further improve the relevant technology, benzenedimethanol was used as a raw material for one-step hydrogenation to prepare 1,4-cyclohexanedimethanol, using 5% Ru / C as a catalyst, the temperature was 100°C, the pressure was 4.9MPa, and the recovery rate of 1,4-cyclohexanedimethanol was 76%. However, the preparation of 1,4-cyclohexanedimethanol from benzenedimethanol has high equipment requirements and low yield.

[0038] In addition, some related technologies also disclose a catalyst for hydrogenating dimethyl 1,4-cyclohexanedicarboxylate to prepare 1,4-cyclohexanedimethanol. The catalyst uses copper, zinc, and aluminum as active components, and uses Mg, Ba, Mn, etc. as additives, and is prepared by a step-by-step precipitation and dynamic crystallization method. The preparation process of this catalyst is relatively complicated, with many by-products that are difficult to separate and purify, and produces a lot of wastewater. And some related technologies disclose a method of using SiO2 as a catalyst by precipitation method. 2 The catalyst is a carrier and copper is an active component. However, the preparation conditions of the catalyst are complicated, a large amount of organic wastewater is generated, and sodium ions are easily introduced into the catalyst as impurities.

[0039] To achieve the above object, according to the embodiment of the first aspect of the present application, a method for preparing a catalyst for synthesizing 1,4-cyclohexanedimethanol is proposed. Figure 1 As shown, the following steps are included:

[0040] S1: dissolving at least one of a soluble zinc salt, a calcium salt, a copper salt, a nickel salt, and a magnesium salt and an auxiliary salt in deionized water to obtain a mixed solution;

[0041] S2: After adding a certain amount of alkaline precipitant to the mixed solution, adjust the pH value to 8-12;

[0042] S3: After adding a certain amount of silicide to the mixed solution, heating in an oil bath at 80-140° C. for 1-8 hours to obtain a first viscous material;

[0043] The first viscous material is centrifuged and washed to obtain a second viscous material, which is then dried. The second viscous material has a pH value of 7.5-8. The catalyst is then calcined at 300-800°C for 4-8h to obtain a catalyst. The catalyst is tableted, crushed, and sieved in sequence.

[0044] In some embodiments, the zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc nitrate and zinc chloride;

[0045] And / or, the calcium salt is selected from at least one of calcium sulfate, calcium acetate, calcium nitrate and calcium chloride;

[0046] And / or, the copper salt is selected from at least one of copper sulfate, copper acetate, copper nitrate and copper chloride;

[0047] And / or, the nickel salt is selected from at least one of nickel sulfate, nickel acetate, nickel nitrate and nickel chloride;

[0048] And / or, the magnesium salt is selected from at least one of magnesium sulfate, magnesium acetate, magnesium nitrate and magnesium chloride;

[0049] And / or, the auxiliary salt is at least one of metal nitrate, metal sulfate, metal acetate and metal chloride; the metal element includes Au element, Pt element, Pd element, Ag element, Ru element, Mn element, Ti element, Re element or Ce element.

[0050] In some embodiments, the molar ratio of zinc salt to the total amount of calcium salt, copper salt, nickel salt, magnesium salt and auxiliary salt is 0.1-10.

[0051] In some embodiments, the pH of the mixed solution is in the range of 8-12, and the pH is adjusted by an alkaline precipitant.

[0052] In some embodiments, the alkaline precipitant includes one of ammonia water, sodium bicarbonate, sodium hydroxide, etc.;

[0053] In some embodiments, the silicide includes at least one of silicon tetrachloride, methyl orthosilicate, ethyl orthosilicate, silica sol, or sodium silicate;

[0054] and / or, with silicide SiO 2 The mass ratio of the silicide to the mixed solution is 1-50.

[0055] In some embodiments, the pH of the second adhesive is in the range of 7.5-8.

[0056] According to the second aspect of the present application, a catalyst for synthesizing 1,4-cyclohexanedimethanol is provided, which is obtained by using the preparation method in any of the above embodiments, wherein the catalyst is SiO 2 As a carrier, zinc, calcium, copper, nickel and magnesium are used as active ingredients, and the metal M in the auxiliary salt is used as an auxiliary agent; wherein the mass fraction of the total amount of zinc, calcium, copper, nickel and magnesium is 3-60% based on the catalyst, the mass fraction of the metal M is 0.1-20%, and the rest is SiO 2 .

[0057] According to the third aspect of the present application, the catalyst in any of the above embodiments is used in the hydrogenation of dimethyl 1,4-cyclohexanedicarboxylate to prepare 1,4-cyclohexanedimethanol. The catalyst is loaded into a fixed bed micro-reactor and reduced with a reducing gas. The reduction parameters are: the gas flow rate is 20-1800h -1 , pressure is 1-6MPa, temperature is 200-800℃, time is 0.5-24h, and heating rate is 1-15℃ / min.

[0058] In some embodiments, the reducing gas is hydrogen or an inert gas containing hydrogen; in the inert gas containing hydrogen, the volume fraction of hydrogen is 1-100%.

[0059] According to the fourth aspect of the present application, the catalyst in any of the above embodiments is used in the preparation of 1,4-cyclohexanedimethanol from a methanol solution of dimethyl 1,4-cyclohexanedicarboxylate, with hydrogen and a methanol solution of dimethyl 1,4-cyclohexanedicarboxylate as raw materials, and the reaction parameters are controlled as follows: the reaction pressure is 1-10 MPa, the reaction temperature is 180-400°C, the mass fraction of the methanol solution of dimethyl 1,4-cyclohexanedicarboxylate is 3-80%, and the raw material liquid hourly space velocity is 0.1-5h -1 , the hydrogen ester molar ratio is 50-400.

[0060] To facilitate further understanding of the present application, the scheme of the present application is further described below in conjunction with the embodiments. Those skilled in the art will understand that the description in the present application is only part of the examples, and any other suitable specific examples are within the scope of the present application.

[0061] Example 1

[0062] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol, and the specific steps and parameters are as follows: 2.35 g of zinc nitrate trihydrate, 3.33 g of calcium carbonate and 2.31 g of copper nitrate trihydrate are weighed and dissolved in 100 mL of deionized water, 100 mL of ammonia water is added, and the mixture is fully stirred to dissolve, and then 100 mL of silica sol is added, and the mixture is heated to 120° C., and fully stirred for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material, and its pH value is 11. The second viscous material is obtained by centrifugal washing and filtration, and its pH value is 7.5. The second viscous material is placed in an oven at 120° C. for drying, and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0063] Catalyst reduction The catalyst obtained by the above operation was crushed, tableted, and sieved into 20-40 mesh. 2 g of catalyst was weighed and loaded into the reaction tube. 2 The temperature was raised to 5 °C / min and the gas flow rate was 300 h. -1, the reaction pressure is 2MPa.

[0064] Catalyst evaluation: After the catalyst was reduced by hydrogen, the methanol solution of 1,4-cyclohexanedicarboxylic acid dimethyl ester was fed through a micro-metering pump for reaction. The reaction temperature was 210°C and the raw material liquid hourly space velocity was 0.5h -1 ; The hydrogen-ester molar ratio is 230. After the reaction is fully completed, the reaction liquid is taken every two hours for gas chromatography analysis to calculate the conversion rate of dimethyl 1,4-cyclohexanedicarboxylate and the selectivity of 1,4-cyclohexanedimethanol. The results are shown in Table 1.

[0065] Example 2

[0066] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol. 20.4 g of nickel nitrate trihydrate, 4.4 g of magnesium nitrate and 0.79 g of copper nitrate are weighed and dissolved in 100 mL of deionized water. 100 mL of sodium bicarbonate solution is added and stirred thoroughly to dissolve. 100 mL of methyl orthosilicate is added and heated to 120° C. and stirred thoroughly for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material having a pH value of 10. The second viscous material having a pH value of 7.8 is obtained by centrifugal washing and filtration. The second viscous material is placed in an oven at 120° C. to dry and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0067] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0068] Example 3

[0069] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol: 6.5 g of copper sulfate, 3.31 g of nickel nitrate and 8.02 g of magnesium nitrate are weighed and dissolved in 100 mL of deionized water, 100 mL of ammonia water is added, and the mixture is fully stirred to dissolve, and then 100 mL of methyl silane is added, and the mixture is heated to 120° C., and fully stirred for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material with a pH value of 11. A second viscous material with a pH value of 8 is obtained by centrifugal washing and filtration, and the mixture is dried in an oven at 120° C., and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0070] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0071] Example 4

[0072] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol: 9.5 g of copper sulfate and 2.45 g of cerium nitrate hexahydrate are weighed and dissolved in 100 mL of deionized water, 100 mL of sodium hydroxide solution is added, and the mixture is fully stirred to dissolve, and then 100 mL of ethyl orthosilane is added, and the mixture is heated to 120° C., and fully stirred for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material having a pH value of 9, and a second viscous material having a pH value of 7.5 is obtained by centrifugal washing and filtration. The second viscous material is placed in an oven at 120° C. for drying, and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0073] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0074] Example 5

[0075] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol: 9.5 g of copper sulfate, 8.33 g of zinc acetate, and 2.45 g of cerium nitrate hexahydrate are weighed and dissolved in 100 mL of deionized water, 100 mL of ammonia water is added, and the mixture is stirred thoroughly to dissolve, and then 100 mL of ethyl orthosilane is added, and the mixture is heated to 120° C., stirred thoroughly for 5 h, and aged for more than 10 hours to obtain a first viscous material with a pH value of 11. A second viscous material with a pH value of 7.9 is obtained by centrifugal washing and filtration, and the second viscous material is placed in an oven at 120° C. for drying, and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0076] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0077] Example 6

[0078] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol. 8.3 g of copper sulfate, 3.23 g of zinc acetate and 6.3 g of magnesium acetate are weighed and dissolved in 100 mL of deionized water. 100 mL of ammonia water is added and stirred thoroughly to dissolve. 100 mL of ethyl orthosilane is added and heated to 120° C. and stirred thoroughly for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material having a pH value of 12. A second viscous material having a pH value of 7.6 is obtained by centrifugal washing and filtration. The second viscous material is placed in an oven at 120° C. for drying and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0079] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0080] Example 7

[0081] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol. 24.8 g of copper nitrate trihydrate and 2.45 g of cerium nitrate hexahydrate are weighed and dissolved in 100 mL of deionized water. 100 mL of ammonia water is added and stirred thoroughly to dissolve. Then 100 mL of silica sol is added, and the mixture is heated to 120° C. and stirred thoroughly for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material having a pH value of 10. A second viscous material having a pH value of 8 is obtained by centrifugal washing and filtration. The second viscous material is placed in an oven at 120° C. for drying and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0082] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0083] Example 8

[0084] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol. 24.8 g of copper nitrate trihydrate and 2.45 g of cerium nitrate hexahydrate are weighed and dissolved in 100 mL of deionized water. 100 mL of ammonia water is added and stirred thoroughly to dissolve. Then 100 mL of silica sol is added, and the mixture is heated to 120° C. and stirred thoroughly for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material having a pH value of 10. The second viscous material having a pH value of 7.5 is obtained by centrifugal washing and filtration. The second viscous material is placed in an oven at 120° C. for drying and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0085] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0086] Example 9

[0087] The present embodiment provides a preparation method for a catalyst for synthesizing 1,4-cyclohexanedimethanol. 24.8 g of copper nitrate trihydrate and 8.33 g of silver acetate are weighed and dissolved in 100 mL of deionized water. 100 mL of ammonia water is added and stirred thoroughly to dissolve. Then 100 mL of sodium silicate is added and heated to 120° C. and stirred thoroughly for 5 h. The mixture is aged for more than 10 hours to obtain a first viscous material having a pH value of 10. A second viscous material having a pH value of 8 is obtained by centrifugal washing and filtration. The second viscous material is placed in an oven at 120° C. for drying and finally calcined in a muffle furnace at 400° C. for 5 h to obtain a catalyst.

[0088] The catalyst reduction conditions and evaluation conditions were the same as in Example 1. The results are shown in Table 1.

[0089] Example 10

[0090] This embodiment provides a preparation method for synthesizing a 1,4-cyclohexanedimethanol catalyst, weighing 24.8 g of copper nitrate trihydrate and 4.9 g of cerium nitrate hexahydrate, dissolving them in 100 mL of deionized water, adding 100 mL of sodium bicarbonate solution, stirring and dissolving them, adding 100 mL of sodium silicate, heating to 120°C, stirring them for 5 hours, aging for more than 10 hours to obtain a first viscous material, the pH value of which is 11, and filtering by centrifugation to obtain a second viscous material, the pH value of which is 7.7, placing it in a 120°C oven to dry, and finally calcining it in a 400°C muffle furnace for 5 hours to obtain a catalyst. The catalyst reduction conditions and evaluation conditions are the same as those in Example 1, and the results are shown in Table 1.

[0091] Table 1 Catalyst evaluation results of various examples

[0092] catalyst Pressure / Mpa Temperature / ℃ Hydrogen ester molar ratio <![CDATA[Liquid hourly space velocity / h -1 > Conversion rate / % Selectivity / % Example 1 2.5 220 120 0.2 85.0 92.9 Example 2 2.0 200 150 0.3 93.6 89.9 Example 3 2.5 210 200 0.25 96.1 96.3 Example 4 2.5 220 100 0.25 98.7 92.5 Example 5 3.0 235 120 0.5 96.5 93.7 Example 6 3.0 200 100 1.6 96.8 91.2 Example 7 3.0 200 130 1.8 97.3 95.0 Example 8 3.0 220 80 0.6 97.9 95.3 Example 9 3.0 200 80 1.2 97.1 94.6 Example 10 5.0 180 150 0.7 98.9 95.2

[0093] As can be seen from Table 1, the catalyst has a very high conversion rate for dimethyl 1,4-cyclohexanedicarboxylate and an excellent selectivity for 1,4-cyclohexanedimethanol, showing good application prospects.

[0094] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0095] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for preparing a catalyst for synthesizing 1,4-cyclohexanedimethanol, characterized in that: It includes the following steps: Dissolving at least one of soluble zinc salt, calcium salt, copper salt, nickel salt, and magnesium salt and an auxiliary salt in deionized water to obtain a mixed solution; Adding a certain amount of alkaline precipitant to the mixed solution and reacting for a certain time; After adding a certain amount of silicide, heating in an oil bath at 80-140° C. for 1-8 hours obtains a first viscous material; The first viscous material is aged, centrifuged, washed, and then dried to obtain a second viscous material, and then calcined at 300-800° C. for 4-8 hours to obtain a catalyst, and the catalyst is successively tableted, crushed, and sieved.

2. The preparation method according to claim 1, characterized in that: The zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc nitrate and zinc chloride; And / or, the calcium salt is selected from at least one of calcium sulfate, calcium acetate, calcium nitrate and calcium chloride; And / or, the copper salt is selected from at least one of copper sulfate, copper acetate, copper nitrate and copper chloride; And / or, the nickel salt is selected from at least one of nickel sulfate, nickel acetate, nickel nitrate and nickel chloride; And / or, the magnesium salt is selected from at least one of magnesium sulfate, magnesium acetate, magnesium nitrate and magnesium chloride; And / or, the auxiliary salt is at least one of metal nitrate, metal sulfate, metal acetate and metal chloride; the metal element includes Au element, Pt element, Pd element, Ag element, Ru element, Mn element, Ti element, Re element or Ce element.

3. The preparation method according to claim 1 or 2, characterized in that: The molar ratio of the zinc salt to the total amount of the calcium salt, the copper salt, the nickel salt, the magnesium salt and the auxiliary salt is 0.1-10.

4. The preparation method according to claim 3, characterized in that: The alkaline precipitant is selected from ammonia water, sodium bicarbonate, sodium hydroxide and the like.

5. The preparation method according to claim 3, characterized in that: The pH value of the mixed solution is in the range of 8-12, and the pH value is adjusted by an alkaline precipitant.

6. The preparation method according to claim 3, characterized in that: The silicide comprises at least one of silicon tetrachloride, methyl orthosilicate, ethyl orthosilicate, silica sol or sodium silicate; And / or, based on the mass of the silicide and SiO2, the mass ratio of the silicide to the mixed solution is 1-50.

7. The preparation method according to claim 4, characterized in that: The pH range of the first adhesive is 8-12.

8. A catalyst for synthesizing 1,4-cyclohexanedimethanol, characterized in that: The catalyst is obtained by the preparation method described in any one of claims 1 to 6, wherein the catalyst uses SiO2 as a carrier, zinc, calcium, copper, nickel, and magnesium as active ingredients, and the metal M in the auxiliary salt is an auxiliary; wherein based on the catalyst, the mass fraction of the total amount of zinc, calcium, copper, nickel, and magnesium is 3-60%, the mass fraction of metal M is 0.1-20%, and the rest is SiO2.

9. The catalyst of claim 8 is used in the preparation of 1,4-cyclohexanedimethanol by hydrogenation of dimethyl 1,4-cyclohexanedicarboxylate, characterized in that: The catalyst is loaded into a fixed bed micro-reactor and reduced with reducing gas. The reduction parameters are: gas flow rate is 20-1800h -1 , pressure is 1-6MPa, temperature is 200-800℃, time is 0.5-24h, and heating rate is 1-15℃ / min.

10. The use according to claim 9, characterized in that: The reducing gas is hydrogen or an inert gas containing hydrogen; in the inert gas containing hydrogen, the volume fraction of hydrogen is 1-100%.

11. The catalyst of claim 8 is used in the preparation of 1,4-cyclohexanedimethanol from a methanol solution of dimethyl 1,4-cyclohexanedicarboxylate, characterized in that: The reaction parameters are as follows: the reaction pressure is 1-10 MPa, the reaction temperature is 180-400°C, the mass fraction of the methanol solution of dimethyl 1,4-cyclohexanedicarboxylate is 3-80%, and the raw material liquid hourly space velocity is 0.1-5 h -1 , the hydrogen ester molar ratio is 50-400.

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