Supported hydrogenation catalyst as well as preparation method and application thereof

Abstract

The invention relates to a supported hydrogenation catalyst as well as a preparation method and application thereof, the novel supported hydrogenation catalyst is prepared by using nano aluminum oxide activated by methanol as a carrier, the novel supported hydrogenation catalyst has relatively high activity on hydrogenation of bisphenol compounds, and the trans-isomer proportion of hydrogenated bisphenol A is relatively high; meanwhile, metal components are dispersed more uniformly by utilizing adsorption sites generated by methanol activation, generation of deep hydrogenation products of bisphenol compounds is reduced, the hydrogenation performance of the supported hydrogenation catalyst on bisphenol A is improved, the loading capacity of noble metal active components is effectively reduced, and thus the preparation cost of the catalyst is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of organic catalytic synthesis, and in particular to a supported hydrogenation catalyst and a preparation method and application thereof. Background Art

[0002] Hydrogenated bisphenol A (HBPA), also known as 4,4'-isopropylmethylenebiscyclohexanol, is an important raw material for the synthesis of unsaturated polyester resins and epoxy resins. These resins are widely used in medical device components, specialty resins, composite materials, etc. due to their water resistance, drug resistance, excellent thermal stability and light stability, and non-toxicity.

[0003] Hydrogenated bisphenol A is generally a product obtained by hydrogenating bisphenol A (BPA) in a solution state through the action of a catalyst. The specific process includes adding bisphenol A, solvent and catalyst into a high-pressure reactor, heating and introducing hydrogen, reacting for a period of time under certain temperature and pressure conditions, and finally cooling and separating to obtain the product. The key to its preparation lies in the selection of hydrogenation catalyst and process optimization.

[0004] US2118954A discloses a method for converting bisphenol A into hydrogenated bisphenol A by liquid phase hydrogenation reaction using a supported nickel-based catalyst. The reaction needs to be carried out in an intermittent reactor at 200°C and 10-20 MPa, the reaction time is relatively long, and the yield of the target product is relatively low.

[0005] CN1375484A discloses a method for preparing hydrogenated bisphenol A using a ruthenium catalyst supported on silicon dioxide. By using a fixed bed hydrogenation process at a temperature range of 50 to 250°C and a pressure of 0.5 to 15 MPa, by adjusting the molar ratio of hydrogen to bisphenol A to 6:1 to 30:1, a 100% conversion rate can be achieved within 40 hours while maintaining an average selectivity of 96%.

[0006] In the preparation process of hydrogenated bisphenol A, the trans isomer has attracted much attention because of its structural symmetry, which shows better mechanical properties in polymer applications. However, the selectivity of trans isomers in the prior art is generally low, about 30-45%, and domestic hydrogenated bisphenol A products mainly rely on imports. The domestic industry is still in its infancy and faces challenges of small scale, high price and unstable quality. CN109678661A discloses a device for continuous preparation of hydrogenated bisphenol A and a continuous preparation method of hydrogenated bisphenol A. By adopting a supported nickel-based hydrogenation catalyst and a continuous hydrogenation process, the product purity is increased to 98% at a lower reaction pressure and temperature, and the trans isomer content is also increased to about 60%. However, the production cycle is extended, energy consumption is increased, and production costs are further increased.

[0007] Among the three isomers of hydrogenated bisphenol A, the trans isomer is more valuable in applications. Therefore, developing efficient, low-cost, highly selective catalysts and optimizing production processes to produce hydrogenated bisphenol A with a high proportion of trans isomers has become a key issue that needs to be urgently addressed in the current industry. Summary of the invention

[0008] In view of the deficiencies in the prior art, the object of the present invention is to provide a supported hydrogenation catalyst and a preparation method and application thereof. The supported hydrogenation catalyst has the characteristics of high efficiency, low cost and high selectivity, and is suitable for industrial-scale production.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a method for preparing a supported hydrogenation catalyst, the preparation method comprising the following steps:

[0011] (1) mixing an aluminum salt solution with citric acid to obtain a sol-gel; subjecting the obtained sol-gel to a first heat treatment to obtain a nano-alumina carrier; and subjecting the obtained nano-alumina carrier to an activation treatment with methanol to obtain an activated alumina carrier;

[0012] (2) The ruthenium source, the solvent and the activated alumina carrier obtained in step (1) are mixed and impregnated, and the obtained catalyst precursor is subjected to a second heat treatment and a hydrogen reduction treatment in sequence to obtain the supported hydrogenation catalyst.

[0013] The preparation method of the supported hydrogenation catalyst provided by the present invention comprises the following steps: firstly, a nano-alumina carrier is prepared by a sol-gel method, and the nano-alumina carrier is further activated by methanol, so that the acidity and alkalinity of the catalyst are enhanced, the hydrogenation of C=O in the raw material is inhibited, the generation of deep hydrogenation products of bisphenol compounds is reduced, and the generation of polymers is reduced; and the methanol activation also increases the adsorption sites of the carrier for the ruthenium component, so that the active component is more evenly dispersed on the surface of the carrier, and the synergistic effect of the two improves the activity of the product, and the ratio of the trans isomer of the hydrogenated bisphenol product is further increased by the heat treatment step, because the cis isomer has a higher internal energy and can often be converted into the trans isomer by heating, that is, isomerization can be achieved by supplementing sufficient energy at high temperature. Then, the excellent dissociation ability of the noble metal ruthenium to hydrogen can be used to achieve the catalytic hydrogenation of bisphenol A. In addition, the nano-alumina carrier can also produce a hydrogen overflow effect, which effectively reduces the loading amount of the noble metal active component ruthenium, while still maintaining a high activity, thereby reducing the production cost of the catalyst.

[0014] Preferably, the aluminum salt in the aluminum salt solution of step (1) comprises any one of aluminum nitrate, aluminum chloride, aluminum sulfate or aluminum isopropoxide, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of aluminum nitrate and aluminum chloride, a combination of aluminum chloride, aluminum sulfate and aluminum isopropoxide, or a combination of aluminum nitrate, aluminum chloride, aluminum sulfate and aluminum isopropoxide.

[0015] Preferably, the molar ratio of aluminum ions to citric acid in the aluminum salt solution of step (1) is (0.2-1.5):1, for example, it can be 0.2:1, 0.8:1, 1:1, 1.2:1 or 1.5:1, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable, preferably (0.8-1.2):1.

[0016] Preferably, the mixing temperature in step (1) is 50-80°C, for example, 50°C, 60°C, 65°C, 70°C or 80°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0017] Preferably, the first heat treatment in step (1) comprises evaporation, drying and calcination performed sequentially.

[0018] Preferably, the evaporation temperature is 80-100° C. and the evaporation time is 3-5 h.

[0019] The evaporation temperature is 80-100° C., for example, 80° C., 85° C., 90° C., 95° C. or 100° C., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0020] The evaporation time is 3-5 hours, for example, 3 hours, 3.5 hours, 4 hours, 4.5 hours or 5 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0021] Preferably, the drying temperature is 108-112° C. and the drying time is 3.5-4.5 h.

[0022] The drying temperature is 108-112° C., for example, 108° C., 109° C., 110° C., 111° C. or 112° C., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] The drying time is 3.5-4.5 hours, for example, 3.5 hours, 3.8 hours, 4 hours, 4.2 hours or 4.5 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0024] Preferably, the calcination temperature is 400-600° C. and the calcination time is 2-6 hours.

[0025] The calcination temperature is 400-600°C, for example, 400°C, 450°C, 500°C, 550°C or 600°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] The calcination time is 2-6 hours, for example, 2 hours, 3 hours, 4 hours, 5 hours or 6 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0027] Preferably, the specific steps of the activation treatment in step (1) include: mixing the nano-alumina carrier with methanol and heating the mixture under reflux to the boiling point of methanol for 5-10 hours; after solid-liquid separation of the mixture, washing the obtained solid phase with methanol and drying it.

[0028] The heating reflux duration is 5-10 hours, for example, 5 hours, 6 hours, 8 hours, 9 hours or 10 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0029] Preferably, the temperature of the methanol washing is 20-30°C, for example, 20°C, 22°C, 25°C, 28°C or 30°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0030] Preferably, the methanol washing is performed twice, each washing time is 23-25 ​​hours, for example, it can be 23 hours, 23.5 hours, 24 hours, 24.5 hours or 25 hours, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0031] Preferably, the drying temperature is 78-82° C. and the drying time is 11-13 hours.

[0032] The drying temperature is 78-82°C, for example, 78°C, 79°C, 80°C, 81°C or 82°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0033] The drying time is 11-13 hours, for example, 11 hours, 11.5 hours, 12 hours, 12.5 hours or 13 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0034] Preferably, the ruthenium source in step (2) comprises any one of ruthenium chloride, ruthenium acetylacetonate or ruthenium acetate, or a combination of at least two of them. Typical but non-limiting combinations include a combination of ruthenium chloride and ruthenium acetylacetonate, a combination of ruthenium acetylacetonate and ruthenium acetate, or a combination of ruthenium chloride, ruthenium acetylacetonate and ruthenium acetate.

[0035] Preferably, the solvent in step (2) comprises deionized water.

[0036] Preferably, the solid content of the catalyst precursor in step (2) is 5-12%, for example, 5%, 6%, 8%, 10% or 12%, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0037] Preferably, the temperature of the mixed impregnation in step (2) is 20-30° C. and the time is 1.8-2.2 h.

[0038] The temperature of the mixed impregnation is 20-30°C, for example, 20°C, 22°C, 25°C, 28°C or 30°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0039] The mixed impregnation time is 1.8-2.2 hours, for example, 1.8 hours, 1.9 hours, 2 hours, 2.1 hours or 2.2 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0040] Preferably, the mixed impregnation in step (2) is allowed to stand for 0.4-0.6 h, for example, 0.4 h, 0.45 h, 0.5 h, 0.55 h or 0.6 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0041] Preferably, the second heat treatment in step (2) comprises drying and calcining performed sequentially.

[0042] Preferably, the drying temperature is 88-92° C. and the drying time is 23-25 ​​h.

[0043] The drying temperature is 88-92° C., for example, 88° C., 89° C., 90° C., 91° C. or 92° C., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0044] The drying time is 23-25 ​​hours, for example, 23 hours, 23.5 hours, 24 hours, 24.5 hours or 25 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0045] Preferably, the calcination is: heating to 200-500° C. at a heating rate of 1.8-2.2° C. / min, and calcining for 2.8-3.2 h.

[0046] The heating rate of the calcination is 1.8-2.2°C / min, for example, 1.8°C / min, 1.9°C / min, 2°C / min, 2.1°C / min or 2.2°C / min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0047] The temperature end point of the calcination is 200-500°C, for example, 200°C, 250°C, 300°C, 400°C or 500°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0048] The calcination time is 2.8-3.2 h, for example, 2.8 h, 2.9 h, 3 h, 3.1 h or 3.2 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0049] Preferably, the temperature of the hydrogen reduction treatment in step (2) is 200-400° C. and the time is 1-3 h.

[0050] The temperature of the hydrogen reduction treatment is 200-400°C, for example, 200°C, 250°C, 300°C, 350°C or 400°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0051] The time of the hydrogen reduction treatment is 1-3 hours, for example, 1 hour, 1.5 hours, 2 hours, 2.5 hours or 3 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0052] Preferably, hydrogen is continuously introduced during the hydrogen reduction treatment in step (2).

[0053] In a second aspect, the present invention provides a supported hydrogenation catalyst, wherein the supported hydrogenation catalyst is prepared by the method for preparing the supported hydrogenation catalyst according to the first aspect;

[0054] The ruthenium loading in the supported hydrogenation catalyst is 0.5-1.5wt%, for example, 0.5wt%, 0.8wt%, 1wt%, 1.2wt% or 1.5wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable, preferably 0.8wt%.

[0055] The supported hydrogenation catalyst provided by the present invention can achieve a conversion rate of 99.9% at a low noble metal loading, and the selectivity of hydrogenated bisphenol A can reach 98.3%, wherein the proportion of trans isomers in hydrogenated bisphenol A can reach 75%.

[0056] In a third aspect, the present invention provides an application of the supported hydrogenation catalyst as described in the second aspect, wherein the supported hydrogenation catalyst is used in catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, and the preparation method comprises the following steps:

[0057] Bisphenol A, an organic solvent and a supported hydrogenation catalyst are mixed and subjected to a catalytic hydrogenation reaction. The obtained reaction liquid is centrifuged to recover the supported hydrogenation catalyst, and the remaining liquid phase is evaporated and recrystallized in sequence to obtain the hydrogenated bisphenol A.

[0058] The invention uses a supported hydrogenation catalyst in the catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, which can effectively improve the raw material conversion rate and the selectivity of the trans isomer of the hydrogenated bisphenol product and meet the requirements of industrial production.

[0059] Preferably, the organic solvent comprises any one of cyclohexane, isopropanol or ethyl acetate, preferably isopropanol.

[0060] Preferably, the mass ratio of the organic solvent to bisphenol A is (2-5):1, for example, 2:1, 3:1, 4:1 or 5:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0061] Preferably, the mass ratio of bisphenol A to supported hydrogenation catalyst is (10-30):1, for example, 10:1, 15:1, 20:1, 25:1 or 30:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0062] Preferably, nitrogen replacement is performed three times before the catalytic hydrogenation reaction.

[0063] Preferably, the temperature of the catalytic hydrogenation reaction is 100-150°C, for example, 100°C, 110°C, 120°C, 130°C or 150°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable, preferably 110-130°C.

[0064] Preferably, the hydrogen pressure of the catalytic hydrogenation reaction is 2-5 MPa, for example, 2 MPa, 3 MPa, 3.5 MPa, 4 MPa or 5 MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable, preferably 3-4 MPa.

[0065] Preferably, the stirring speed of the catalytic hydrogenation reaction is 780-820 rpm, for example, 780 rpm, 790 rpm, 800 rpm, 810 rpm or 820 rpm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0066] Preferably, the reaction time of the catalytic hydrogenation reaction is 1-6 h, for example, 1 h, 3 h, 4 h, 5 h or 6 h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable, preferably 3-5 h.

[0067] Preferably, ethyl acetate is added in the recrystallization in an amount of 20-50 g, for example, 20 g, 25 g, 30 g, 40 g or 50 g, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] (1) The preparation method of the supported hydrogenation catalyst provided by the present invention comprises the following steps: firstly, a nano-alumina carrier is prepared by a sol-gel method, and the nano-alumina carrier is further activated by methanol, thereby reducing the generation of deep hydrogenation products of bisphenol compounds and the generation of polymers; the adsorption sites of the carrier for the ruthenium component are increased, so that the active component is more evenly dispersed on the surface of the carrier, and the synergistic effect of the two improves the activity of the product, and the ratio of the trans isomer of the hydrogenated bisphenol product is further increased by the heat treatment step, and then the catalytic hydrogenation of bisphenol A can be achieved by utilizing the excellent dissociation ability of the noble metal ruthenium to hydrogen. In addition, the nano-alumina carrier can also produce a hydrogen overflow effect, effectively reducing the loading amount of the noble metal active component ruthenium, while still maintaining a high activity, thereby reducing the production cost of the catalyst.

[0070] (2) The supported hydrogenation catalyst provided by the present invention can achieve a conversion rate of 99.9% at a low noble metal loading, and the selectivity of hydrogenated bisphenol A can reach 98.3%, wherein the proportion of the trans isomer in hydrogenated bisphenol A can reach 75%. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 is the XRD diagram of the supported hydrogenation catalyst provided in Example 1 of the present invention;

[0072] Figure 2 is a SEM image of the supported hydrogenation catalyst provided in Example 1 of the present invention;

[0073] Figure 3 is the N of the supported hydrogenation catalyst provided in Example 1 of the present invention and Comparative Example 1 2 Adsorption-desorption isotherm plot. DETAILED DESCRIPTION

[0074] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only used to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0075] Example 1

[0076] This embodiment provides a supported hydrogenation catalyst, in which the ruthenium loading amount in the supported hydrogenation catalyst is 0.8 wt %.

[0077] The preparation method of the supported hydrogenation catalyst comprises the following steps:

[0078] (1) A sol-gel is obtained by mixing an aluminum nitrate solution with citric acid at 60° C., wherein the molar ratio of aluminum ions in the aluminum nitrate solution to citric acid is 1:1; the obtained sol-gel is sequentially evaporated at 90° C. for 4 hours, dried at 110° C. for 4 hours, and calcined at 500° C. for 4 hours to obtain a nano-alumina carrier; the nano-alumina carrier is mixed with methanol and heated to reflux to the boiling point of methanol for 8 hours; after the mixture is separated from the solid, the obtained solid phase is washed twice with methanol at 25° C., each washing for 24 hours, and then dried at 80° C. for 12 hours to obtain an activated alumina carrier;

[0079] (2) Ruthenium chloride, deionized water and the activated alumina carrier obtained in step (1) were mixed and impregnated at 25° C. for 2 h. After standing for 0.5 h, the catalyst precursor having a solid content of 10% was dried at 90° C. for 24 h, then heated to 300° C. at a heating rate of 2° C. / min and calcined for 3 h. Then, hydrogen reduction treatment was performed at 300° C. for 2 h, during which hydrogen was continuously introduced to obtain the supported hydrogenation catalyst. The XRD pattern is shown in FIG. Figure 1 As shown, it is consistent with the diffraction peaks in existing literature; SEM images are shown Figure 2 As shown, ruthenium nanoparticles are loaded on the surface of alumina; N 2 Adsorption-desorption isotherm diagram Figure 3 As shown, it is a type IV isotherm with a specific surface area of ​​242 m 2 / g.

[0080] The supported hydrogenation catalyst is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, and the preparation method comprises the following steps:

[0081] Bisphenol A, isopropanol and a supported hydrogenation catalyst are mixed and replaced with nitrogen three times, wherein the mass ratio of isopropanol to bisphenol A is 4:1, and the mass ratio of bisphenol A to the supported hydrogenation catalyst is 20:1; then a catalytic hydrogenation reaction is carried out at 110° C. and a hydrogen pressure of 3.5 MPa, with a stirring speed of 800 rpm and a reaction time of 4 hours. The supported hydrogenation catalyst is recovered by centrifugation of the obtained reaction solution, and the remaining liquid phase is evaporated, and then 30 g of ethyl acetate is added for recrystallization to obtain the hydrogenated bisphenol A.

[0082] Example 2

[0083] This embodiment provides a supported hydrogenation catalyst, in which the ruthenium loading amount in the supported hydrogenation catalyst is 0.8 wt %.

[0084] The preparation method of the supported hydrogenation catalyst comprises the following steps:

[0085] (1) Aluminum chloride solution and citric acid are mixed at 50° C. to obtain a sol-gel, wherein the molar ratio of aluminum ions to citric acid in the aluminum chloride solution is 0.8:1; the obtained sol-gel is sequentially evaporated at 80° C. for 5 h, dried at 108° C. for 4.5 h, and calcined at 400° C. for 6 h to obtain a nano-alumina carrier; the nano-alumina carrier is mixed with methanol and heated to reflux to the boiling point of methanol for 5 h; after the mixture is separated from the solid, the obtained solid phase is washed twice with methanol at 20° C., each washing for 25 h, and then dried at 78° C. for 13 h to obtain an activated alumina carrier;

[0086] (2) Ruthenium acetylacetonate, deionized water and the activated alumina carrier obtained in step (1) are mixed and impregnated at 20°C for 2.2 hours. After standing for 0.4 hours, the catalyst precursor with a solid content of 5% is dried at 88°C for 25 hours, then heated to 200°C at a heating rate of 1.8°C / min, and calcined for 3.2 hours; then, hydrogen reduction treatment is carried out at 200°C for 3 hours, during which hydrogen is continuously introduced to obtain the supported hydrogenation catalyst.

[0087] The supported hydrogenation catalyst is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, and the preparation method comprises the following steps:

[0088] Bisphenol A, isopropanol and a supported hydrogenation catalyst are mixed and replaced with nitrogen three times, wherein the mass ratio of isopropanol to bisphenol A is 2:1, and the mass ratio of bisphenol A to the supported hydrogenation catalyst is 10:1; then a catalytic hydrogenation reaction is carried out at 110° C. and a hydrogen pressure of 4 MPa, with a stirring speed of 780 rpm and a reaction time of 5 h. The supported hydrogenation catalyst is recovered by centrifugation of the obtained reaction solution, and the remaining liquid phase is evaporated, and then 20 g of ethyl acetate is added for recrystallization to obtain the hydrogenated bisphenol A.

[0089] Example 3

[0090] This embodiment provides a supported hydrogenation catalyst, in which the ruthenium loading amount in the supported hydrogenation catalyst is 0.8 wt %.

[0091] The preparation method of the supported hydrogenation catalyst comprises the following steps:

[0092] (1) A sol-gel is obtained by mixing an aluminum sulfate solution with citric acid at 80° C., wherein the molar ratio of aluminum ions to citric acid in the aluminum sulfate solution is 1.2:1; the obtained sol-gel is sequentially evaporated at 100° C. for 3 h, dried at 112° C. for 3.5 h, and calcined at 600° C. for 2 h to obtain a nano-alumina carrier; the nano-alumina carrier is mixed with methanol and heated to reflux to the boiling point of methanol for 10 h; after the mixture is solid-liquid separated, the obtained solid phase is washed twice with methanol at 30° C., each washing for 23 h, and then dried at 82° C. for 11 h to obtain an activated alumina carrier;

[0093] (2) Ruthenium acetate, deionized water and the activated alumina carrier obtained in step (1) are mixed and impregnated at 30°C for 1.8 hours. After standing for 0.6 hours, the catalyst precursor with a solid content of 12% is dried at 92°C for 23 hours, then heated to 500°C at a heating rate of 2.2°C / min, and calcined for 2.8 hours; then, hydrogen reduction treatment is carried out at 400°C for 1 hour, during which hydrogen is continuously introduced to obtain the supported hydrogenation catalyst.

[0094] The supported hydrogenation catalyst is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, and the preparation method comprises the following steps:

[0095] Bisphenol A, isopropanol and a supported hydrogenation catalyst are mixed and replaced with nitrogen three times, wherein the mass ratio of isopropanol to bisphenol A is 5:1, and the mass ratio of bisphenol A to the supported hydrogenation catalyst is 30:1; then a catalytic hydrogenation reaction is carried out at 130° C. and a hydrogen pressure of 3 MPa, with a stirring speed of 820 rpm and a reaction time of 3 h. The supported hydrogenation catalyst is recovered by centrifugation of the obtained reaction solution, and the remaining liquid phase is evaporated, and then 50 g of ethyl acetate is added for recrystallization to obtain the hydrogenated bisphenol A.

[0096] Example 4

[0097] This embodiment provides a supported hydrogenation catalyst. The difference between the preparation method of the supported hydrogenation catalyst and that of Example 1 is that, except that the molar ratio of aluminum ions to citric acid in the aluminum nitrate solution in step (1) is adjusted to 0.2:1, the rest is the same as that of Example 1.

[0098] Example 5

[0099] This embodiment provides a supported hydrogenation catalyst. The difference between the preparation method of the supported hydrogenation catalyst and that of Example 1 is that, except that the molar ratio of aluminum ions to citric acid in the aluminum nitrate solution in step (1) is adjusted to 1.5:1, the rest is the same as that of Example 1.

[0100] Example 6

[0101] This embodiment provides a supported hydrogenation catalyst, which is different from Embodiment 1 in that, except that the ruthenium loading in the supported hydrogenation catalyst is adjusted to 0.5 wt %, the rest is the same as Embodiment 1.

[0102] Example 7

[0103] This embodiment provides a supported hydrogenation catalyst, which is different from Embodiment 1 in that, except that the ruthenium loading in the supported hydrogenation catalyst is adjusted to 1.5 wt %, the rest is the same as Embodiment 1.

[0104] Example 8

[0105] This embodiment provides a supported hydrogenation catalyst, which is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The preparation method is different from that of Example 1 in that, except for adjusting the temperature of the catalytic hydrogenation reaction to 100° C., the rest is the same as that of Example 1.

[0106] Example 9

[0107] This embodiment provides a supported hydrogenation catalyst, which is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The preparation method is different from that of Example 1 in that, except for adjusting the temperature of the catalytic hydrogenation reaction to 150°C, the rest is the same as that of Example 1.

[0108] Example 10

[0109] This embodiment provides a supported hydrogenation catalyst, which is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The preparation method is different from that of Example 1 in that, except for adjusting the hydrogen pressure of the catalytic hydrogenation reaction to 2 MPa, the rest is the same as that of Example 1.

[0110] Embodiment 11

[0111] This embodiment provides a supported hydrogenation catalyst, which is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The preparation method is different from that of Example 1 in that, except for adjusting the hydrogen pressure of the catalytic hydrogenation reaction to 5 MPa, the rest is the same as that of Example 1.

[0112] Comparative Example 1

[0113] This comparative example provides a supported hydrogenation catalyst. The difference between the preparation method of the supported hydrogenation catalyst and that of Example 1 is that the nano-alumina carrier in step (1) is not activated, and the rest is the same as that of Example 1.

[0114] The N of the supported hydrogenation catalyst in this comparative example 2Adsorption-desorption isotherm diagram Figure 3 As shown, it presents a type IV isotherm with a specific surface area of ​​220 m 2 / g.

[0115] Comparative Example 2

[0116] This comparative example provides a supported hydrogenation catalyst, which is different from Example 1 in that, except that the ruthenium loading in the supported hydrogenation catalyst is adjusted to 0.1 wt %, the rest is the same as Example 1.

[0117] Comparative Example 3

[0118] This comparative example provides a supported hydrogenation catalyst, which is different from Example 1 in that, except that the ruthenium loading in the supported hydrogenation catalyst is adjusted to 2 wt %, the rest is the same as Example 1.

[0119] The supported hydrogenation catalysts provided in Examples 1-11 and Comparative Examples 1-3 were used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The conversion rate, selectivity of hydrogenated bisphenol A and selectivity of the trans isomer of hydrogenated bisphenol A were determined by gas chromatography-mass spectrometry using resorcinol as an internal standard. The results are shown in Table 1.

[0120] Table 1

[0121]

[0122] It can be seen from Table 1 that the present invention uses methanol-activated nano-alumina as a carrier for the first time to prepare a new type of supported hydrogenation catalyst, which has high activity for hydrogenation of bisphenol compounds, and the ratio of the trans isomer of hydrogenated bisphenol A can reach up to 75%.

[0123] By comparing Example 1 with Examples 4 and 5, it can be seen that when the molar ratio of aluminum ions to citric acid is low, the alumina yield is not high, and when the molar ratio is high, the alumina nucleation is larger and the agglomeration tendency is greater; by comparing Example 1 with Examples 6 and 7 and Comparative Examples 2 and 3, it can be seen that the ruthenium loading amount needs to be limited within a reasonable range. If the ruthenium loading amount is too low, the activity of the supported hydrogenation catalyst will be significantly reduced, thereby reducing the raw material conversion rate and the trans isomer selectivity of hydrogenated bisphenol A; if the ruthenium loading amount is too high, the raw material conversion rate and the trans isomer selectivity of hydrogenated bisphenol A will be reduced. The isomer selectivity will no longer continue to increase, and the catalyst preparation cost will also increase; by comparing Example 1 with Examples 8-11, it can be seen that the temperature and hydrogen pressure of the catalytic hydrogenation reaction have a certain influence on hydrogenated bisphenol A and the trans isomer selectivity therein. By limiting the two within the preferred range, a higher raw material conversion rate and the trans isomer selectivity of hydrogenated bisphenol A can be obtained; by comparing Example 1 with Comparative Example 1, it can be seen that the nano alumina carrier is not activated, and the raw material conversion rate and the trans isomer selectivity of hydrogenated bisphenol A are significantly reduced.

[0124] In summary, the preparation method of the supported hydrogenation catalyst provided by the present invention first prepares a nano-alumina carrier by a sol-gel method, and the nano-alumina carrier is further activated by methanol, which reduces the generation of deep hydrogenation products of bisphenol compounds and reduces the generation of polymers; the adsorption sites of the carrier for the ruthenium component are increased, so that the active component is more evenly dispersed on the surface of the carrier, and the synergistic effect of the two improves the activity of the product, and the ratio of the trans isomer of the hydrogenated bisphenol product is further increased by the heat treatment step, and then the excellent dissociation ability of the noble metal ruthenium to hydrogen can be used to achieve catalytic hydrogenation of bisphenol A. In addition, the nano-alumina carrier can also produce a hydrogen overflow effect, effectively reducing the loading amount of the noble metal active component ruthenium, while still maintaining a high activity, reducing the catalyst production cost.

[0125] The supported hydrogenation catalyst provided by the present invention can achieve a conversion rate of 99.9% at a low noble metal loading, and the selectivity of hydrogenated bisphenol A can reach 98.3%, wherein the proportion of trans isomers in hydrogenated bisphenol A can reach 75%.

[0126] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a supported hydrogenation catalyst, characterized in that: The preparation method comprises the following steps: (1) mixing an aluminum salt solution with citric acid to obtain a sol-gel; subjecting the obtained sol-gel to a first heat treatment to obtain a nano-alumina carrier; and subjecting the obtained nano-alumina carrier to an activation treatment with methanol to obtain an activated alumina carrier; (2) The ruthenium source, the solvent and the activated alumina carrier obtained in step (1) are mixed and impregnated, and the obtained catalyst precursor is subjected to a second heat treatment and a hydrogen reduction treatment in sequence to obtain the supported hydrogenation catalyst.

2. The preparation method according to claim 1, characterized in that: The aluminum salt in the aluminum salt solution of step (1) includes any one of aluminum nitrate, aluminum chloride, aluminum sulfate or aluminum isopropoxide, or a combination of at least two thereof; Preferably, the molar ratio of aluminum ions to citric acid in the aluminum salt solution of step (1) is (0.2-1.5):1, preferably (0.8-1.2):1; Preferably, the mixing temperature in step (1) is 50-80°C.

3. The preparation method according to claim 1 or 2, characterized in that: Step (1) The first heat treatment includes evaporation, drying and calcination performed in sequence; Preferably, the evaporation temperature is 80-100°C and the time is 3-5h; Preferably, the drying temperature is 108-112°C and the drying time is 3.5-4.5h; Preferably, the calcination temperature is 400-600° C. and the calcination time is 2-6 hours.

4. The preparation method according to any one of claims 1 to 3, characterized in that The specific steps of the activation treatment in step (1) include: mixing the nano-alumina carrier with methanol and heating it under reflux to the boiling point of methanol for 5-10 hours; after the mixture is separated into solid and liquid, washing the obtained solid phase with methanol and drying it; Preferably, the temperature of the methanol washing is 20-30°C; Preferably, the methanol washing is performed twice, each washing for 23-25 ​​hours; Preferably, the drying temperature is 78-82° C. and the drying time is 11-13 hours.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The ruthenium source in step (2) includes any one of ruthenium chloride, ruthenium acetylacetonate or ruthenium acetate, or a combination of at least two thereof; Preferably, the solvent in step (2) comprises deionized water; Preferably, the solid content of the catalyst precursor in step (2) is 5-12%; Preferably, the temperature of the mixed impregnation in step (2) is 20-30° C. and the time is 1.8-2.2 h; Preferably, the mixed impregnation in step (2) is followed by standing for 0.4-0.6 h.

6. The preparation method according to any one of claims 1 to 5, characterized in that: Step (2) the second heat treatment comprises drying and calcining performed sequentially; Preferably, the drying temperature is 88-92°C and the drying time is 23-25h; Preferably, the calcination is: heating to 200-500°C at a heating rate of 1.8-2.2°C / min, and calcining for 2.8-3.2h; Preferably, the temperature of the hydrogen reduction treatment in step (2) is 200-400° C. and the time is 1-3 h; Preferably, hydrogen is continuously introduced during the hydrogen reduction treatment in step (2).

7. A supported hydrogenation catalyst, characterized in that The supported hydrogenation catalyst is prepared by the method for preparing the supported hydrogenation catalyst according to any one of claims 1 to 6; The ruthenium loading in the supported hydrogenation catalyst is 0.5-1.5 wt %.

8. Use of the supported hydrogenation catalyst as claimed in claim 7, characterized in that: The supported hydrogenation catalyst is used for catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The preparation method comprises the following steps: Bisphenol A, an organic solvent and a supported hydrogenation catalyst are mixed and subjected to a catalytic hydrogenation reaction. The obtained reaction liquid is centrifuged to recover the supported hydrogenation catalyst, and the remaining liquid phase is evaporated and recrystallized in sequence to obtain the hydrogenated bisphenol A.

9. The use according to claim 8, characterized in that: The organic solvent includes any one of cyclohexane, isopropanol or ethyl acetate, preferably isopropanol; Preferably, the mass ratio of the organic solvent to bisphenol A is (2-5):1; Preferably, the mass ratio of bisphenol A to supported hydrogenation catalyst is (10-30):1; Preferably, nitrogen substitution is performed before the catalytic hydrogenation reaction.

10. The use according to claim 8 or 9, characterized in that: The temperature of the catalytic hydrogenation reaction is 100-150°C, preferably 110-130°C; Preferably, the hydrogen pressure of the catalytic hydrogenation reaction is 2-5 MPa, preferably 3-4 MPa; Preferably, the stirring speed of the catalytic hydrogenation reaction is 780-820 rpm; Preferably, the reaction time of the catalytic hydrogenation reaction is 1-6h, preferably 3-5h; Preferably, ethyl acetate is added during the recrystallization in an amount of 20-50 g.

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