Copper-silicon catalyst as well as preparation method and application thereof

Abstract

The invention discloses a copper-silicon catalyst as well as a preparation method and application thereof, and the copper-silicon catalyst comprises the following components in percentage by weight: 43-79wt% of silicon dioxide; the content of copper oxide is 15-35 wt%; the content of the auxiliary agent A is 3-10 wt%; the auxiliary agent B accounts for 3-12 wt%; the auxiliary agent A comprises one or more of alkali metal or alkaline earth metal oxides; and the auxiliary agent B comprises one or more of VB to VIIB group metal oxides. The raw materials of the catalyst are cheap and easy to obtain, the reaction condition is mild, the catalyst is environment-friendly, and the prepared catalyst is small in copper species particle size, high in dispersity, high in conversion rate and selectivity and good in stability.

Description

Technical Field

[0001] This invention belongs to the field of catalyst preparation technology, and in particular relates to a copper-silicon catalyst, its preparation method, and its application. Background Technology

[0002] 1-Phenylacetyl alcohol is an important organic intermediate with wide applications in fragrances, pharmaceuticals, and chemicals. For example, it is widely used in food flavorings, flue-cured tobacco leaves, mosquito coils, nonsteroidal anti-inflammatory drugs (NSAIDs), cosmetics, and perfumes.

[0003] In the production of 1-phenylethanol, microbial fermentation is the method currently under research both domestically and internationally. It primarily uses biomass containing specific amino acids as raw materials to produce 1-phenylethanol through microbial fermentation. However, due to the extremely high cost of raw materials, large-scale industrial production is difficult. Other methods use acetophenone as a raw material, employing inorganic hydrides (such as sodium borohydride, hydrazine, etc.) for reduction and catalytic hydrogenation. Traditionally, the former method is generally used to synthesize 1-phenylethanol. However, due to the use of stoichiometric reducing agents, this often causes significant environmental pollution, and product separation is difficult. Considering environmental friendliness, catalytic hydrogenation, especially heterogeneous catalysis, has gained greater acceptance, as it significantly reduces environmental pollution and is both economical and efficient.

[0004] Traditional acetophenone hydrogenation catalysts are mainly divided into noble metal catalysts and non-noble metal catalysts. Noble metal catalysts primarily use precious metals such as Pd, Pt, and Ru as active components. Although they exhibit high activity and selectivity, the high cost of these precious metals leads to high production costs. Furthermore, noble metal catalysts are susceptible to poisoning by sulfides, chlorides, and some oxides, severely affecting their activity and lifespan. Non-noble metal catalysts primarily use metals such as Ni, Co, Cr, and Zn as active components. While they are less expensive, they suffer from drawbacks such as susceptibility to coking, poor high-temperature resistance, easy loss of active components, poor selectivity, and greater environmental impact.

[0005] Copper-silicon catalysts are a novel type of acetophenone hydrogenation catalyst that has attracted considerable attention in recent years. Using SiO2 as a support, the high specific surface area of ​​SiO2 allows copper species to be dispersed in fine particles, resulting in high catalyst activity. Simultaneously, the addition of co-catalysts effectively ensures high selectivity for 1-phenylethanol, giving copper-silicon catalysts excellent performance in both conversion and selectivity. Compared to traditional hydrogenation catalysts, copper-silicon catalysts offer lower raw material costs, higher mechanical strength, longer catalyst lifetime, higher conversion and selectivity, and are environmentally friendly.

[0006] Invention patent CN117085684A discloses a method for preparing NiO-Al2O3-SiO2 catalyst using a co-precipitation method. The obtained catalyst contains 30 wt% NiO, 61 wt% Al2O3, and 9 wt% SiO2. After reduction with hydrogen in a fixed-bed reactor, the catalyst is introduced into an isopropanol solution of acetophenone for hydrogenation. The reaction temperature is 70°C, the reaction pressure is 5 MPa, and the acetophenone liquid hourly space velocity is 0.625 h⁻¹. -1 The conversion rate of acetophenone was 96.73%, and the selectivity of 1-phenylethanol was 97.62%. The process parameters required for the preparation of the catalyst in this invention are relatively stringent, the hydrogenation reaction operation pressure is high, and the yield of 1-phenylethanol is low.

[0007] Invention patent CN112221508A discloses a heterogeneously formed CuZn@C / SiO2 catalyst. This method uses trimellitic acid as the carbon source and obtains the target catalyst through heterogeneous mixing, solvothermal treatment, and tube furnace calcination. The catalyst does not require pre-reduction before use. The hydrogenation reaction uses an ethylbenzene solution of acetophenone as the raw material, with a reaction temperature of 80℃, a reaction pressure of 2.5 MPa, and an acetophenone space velocity of 0.4 h⁻¹. -1 After 300 hours of reaction, the conversion rate of acetophenone was 97.9%, and the selectivity for 1-phenylethanol was 98.1%. This invention involves multiple catalyst preparation steps, and the space velocity for acetophenone reaction is relatively low, resulting in high production costs.

[0008] Invention patent CN115445629A discloses a 50% CuO-42%Al2O3-3%CeO2-3%Sb2O3-2%BaO catalyst prepared by a co-precipitation method. The catalyst is mixed with guar gum powder and aluminum sol to form a clover-shaped catalyst, which is then dried and calcined to obtain the final catalyst. After reduction activation, the catalyst undergoes a fixed-bed hydrogenation reaction of acetophenone using a 25% acetophenone cumene solution as raw material. The reaction temperature is 72℃, the reaction pressure is 2MPa, and the acetophenone space velocity is 0.6h⁻¹. -1 After 240 hours of reaction, the conversion rate of acetophenone was 98.6%, and the selectivity for 1-phenylethanol was 99.1%. The catalyst composition in this invention is relatively complex and costly.

[0009] Invention patent CN119838629A discloses a hydrogenation catalyst prepared by a physical mixing-hydrogen reduction method. The catalyst's mass composition is: 60% Cu-10% MoO3-2.5% F-27.5% SiO2. The acetophenone hydrogenation reaction feedstock is a 30wt% acetophenone ethanol solution, the hydrogenation temperature is 65℃, the pressure is 2MPa, and the weight hourly space velocity is 0.3h. -1After 500 hours of reaction, the conversion rate of acetophenone was 91.8%, and the selectivity for 1-phenylethanol was 99.9%. The acetophenone conversion rate in this invention is relatively low, and the space velocity for the reaction is also low, resulting in high production costs. Summary of the Invention

[0010] In view of this, the present invention aims to provide a copper-silicon catalyst, its preparation method and application, in order to solve the problems of harsh preparation process conditions and high cost of catalysts in the prior art.

[0011] The preparation method features mild process conditions, a wide range of parameter control thresholds, inexpensive and readily available catalyst support raw materials, small copper species particle size and high dispersion on the silica support surface, high catalyst conversion and selectivity, and good stability.

[0012] To achieve the above objectives, the technical solution of the present invention is implemented as follows: A copper-silicon catalyst, comprising, by weight percentage, 43-79 wt% silicon dioxide; Copper oxide 15-35 wt%; Additive A 3-10wt%; Additive B 3-12wt%; Additive A includes one or more oxides of alkali metals or alkaline earth metals; Additive B includes one or more of group VB to VIIB metal oxides.

[0013] Preferably, a copper-silicon catalyst, by weight percentage, comprises 53-72 wt% silicon dioxide; Copper oxide 20-30 wt%; Additive A 3-7wt%; Additive B 5-10wt%.

[0014] Furthermore, additive A is one or more of potassium oxide, sodium oxide, calcium oxide, and magnesium oxide; Preferably, additive A is calcium oxide or magnesium oxide; Additive B is one or more of vanadium pentoxide, niobium pentoxide, tantalum pentoxide, molybdenum trioxide, tungsten trioxide, and manganese dioxide; Preferably, additive B is niobium pentoxide or vanadium pentoxide.

[0015] The above-mentioned method for preparing a copper-silicon catalyst includes the following steps: S1: Silica is uniformly dispersed in deionized water to form a silica suspension, and then precipitant solution I is prepared; S2: Mix the metal salt solution of additive A and the metal salt solution of additive B to form a mixed salt solution. Add the mixed salt solution and the precipitant solution I prepared in step S1 to the silica suspension prepared in step S1. After post-treatment, separate to obtain the solid. S3: Disperse the solid obtained in step S2 in deionized water to form a solid suspension, and then prepare precipitant solution II; S4: Prepare a copper salt solution from copper oxide. Add the copper salt solution and the precipitant solution II prepared in step S3 to the separated solid suspension obtained in step S3. After post-treatment, obtain a copper-silicon catalyst.

[0016] Furthermore, the silica in step S1 is powdered silica with a particle size of 80-2000 mesh; And / or, the silica suspension in step S1 has a silica mass fraction of 10-20 wt%; Preferably, the powdered silica is one or more of opal powder, diatomaceous earth, precipitated silica, nano silica, powdered silica sol, and silica microspheres; Preferably, the particle size of silica is 100-800 mesh; And / or, the molar concentration of precipitant solution I in step S1 is 0.1-2.0 mol / L, preferably, the molar concentration of precipitant solution I is 0.5-1.0 mol / L.

[0017] And / or, the precipitant solution I in step S1 and the precipitant solution II in step S3 are one or more of the following: sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, and ammonium carbonate aqueous solution, and precipitant solution I and precipitant solution II may be the same or different.

[0018] Furthermore, in step S2, the metal salt in the metal salt solution of auxiliary agent A is a soluble metal salt; in step S2, the metal salt in the metal salt solution of auxiliary agent B is a soluble metal salt. Preferably, the metal salt of the metal salt solution of the auxiliary agent A in step S2 is one or two of chloride salt and nitrate salt; more preferably, the metal salt of the metal salt solution of the auxiliary agent A is one or two of calcium nitrate and magnesium nitrate. Preferably, the metal salt of the metal salt solution of the auxiliary agent B in step S2 is one or both of niobium ammonium oxalate and vanadium oxysulfate. And / or, the mass concentration of the mixed salt solution in step S2 is 5-15 wt%; And / or, the solid obtained after post-processing in step S2 includes co-precipitation, aging at a certain temperature for a certain period of time, washing away the remaining salts, and then separating the solid. And / or, the co-precipitation temperature is 30-60℃, preferably 40-50℃; And / or, the pH value of the coprecipitation is 8.0-10.0, preferably 8.0-9.0; And / or, the co-precipitation time is 0.5-3 hours, preferably 1-2 hours; And / or, the aging temperature is 50-90℃, preferably 60-80℃; And / or, the aging time is 1-4 hours, preferably 2-3 hours.

[0019] Further, in step S3, the mass concentration of the separated solid in the solid suspension is 10-20 wt%; the molar concentration of the precipitant solution II is 0.1-2.0 mol / L, preferably, the molar concentration of the precipitant solution II is 0.5-1.0 mol / L; And / or, the post-processing in step S4 to obtain the copper-silicon catalyst includes co-precipitation, aging at a certain temperature for a certain time to obtain a catalyst slurry, separating the solids in the slurry, washing, drying and calcining to obtain the copper-silicon catalyst. And / or, the co-precipitation temperature is 30-60℃, preferably 40-50℃; And / or, the pH of the coprecipitation is 8.0-9.0; And / or, the co-precipitation time is 0.5-3 hours, preferably 1-2 hours; And / or, the aging temperature is 50-100℃, preferably 80-100℃; And / or, the aging time is 1-4 hours, preferably 2-3 hours; And / or, washing is done by water washing and centrifugation; And / or, the drying temperature is 80-120℃, preferably 100-110℃; And / or, the drying time is 12-24 hours, preferably 16-20 hours; And / or, the calcination temperature is 400-800℃, preferably 450-750℃; And / or, the roasting time is 2-8 hours, preferably 4-6 hours.

[0020] The application of the copper-silicon catalyst prepared by the above-mentioned method or the copper-silicon catalyst preparation method described above, wherein the reactors to which the catalyst is applicable include slurry bed reactors, fluidized bed reactors, and fixed bed reactors; And / or, the copper-silicon catalyst is suitable for a reaction temperature of 80-200°C, preferably 100-180°C; And / or, the copper-silicon catalyst is suitable for a reaction pressure of 0.1-10 MPa, preferably 1-5 MPa; Preferably, the copper-silicon catalyst is used in a fixed-bed reactor, and is used after adding a molding aid to the copper-silicon catalyst and molding it into tablets; The molding aid includes graphite, with an addition amount of 1-3 wt%. The molded catalyst is a cylindrical tablet with a diameter of 3-6 mm and a height of 2-5 mm.

[0021] The application of the copper-silicon catalyst prepared by the above-mentioned method in the hydrogenation of acetophenone to 1-phenylethanol: the copper-silicon catalyst is reduced before catalyzing the hydrogenation of acetophenone to 1-phenylethanol. The reduction method of the copper-silicon catalyst includes: pre-reducing the copper-silicon catalyst by introducing a mixture of hydrogen and nitrogen gas; then gradually increasing the proportion of hydrogen in the hydrogen and nitrogen mixture; controlling the hot spot temperature of the catalyst bed to not exceed 220°C during the process; and finally reducing it in a pure hydrogen atmosphere at 220°C for 3-6 hours to obtain an activated catalyst. The obtained activated catalyst is used in the hydrogenation of acetophenone to 1-phenylethanol.

[0022] Furthermore, the hydrogenation reaction is carried out at a pressure of 1-3 MPa and a temperature of 120-180 °C. The feedstock includes 45 wt% acetophenone, 30 wt% 1-phenylethanol, 21.5 wt% ethylbenzene, and 3.5 wt% styrene, with an acetophenone volume hourly space velocity of 0.4-1.0 h⁻¹. -1 ; And / or, the volume hourly space velocity (VHSV) of the hydrogen and nitrogen mixture is 300-900 h⁻¹. -1 ; And / or, the volume fraction of H2 in the mixture of hydrogen and nitrogen does not exceed 10%; And / or, pre-restore for at least 1 hour.

[0023] This invention relates to a copper-silicon catalyst for the hydrogenation of acetophenone to 1-phenylethanol and its application. The catalyst comprises an active component of copper oxide, a support of silica, and auxiliary agents A and B. A is one or more oxides of alkali metals or alkaline earth metals, and B is one or more oxides of metals from groups VB to VIIB. The catalyst is prepared using a stepwise co-precipitation method, with the following specific steps: First, powdered silica is uniformly dispersed in water to form a suspension, and precipitant solution I is prepared simultaneously. Second, a mixed salt solution of metals contained in additives A and B is added to the silica suspension in parallel with precipitant solution I for the first step of co-precipitation. After the reaction, the remaining salts are washed away, and the solid is separated. The separated solid is then dispersed in water again to form a suspension, and precipitant solution II is prepared simultaneously. A copper salt solution is added to the suspension in parallel with precipitant solution II for the second step of co-precipitation. After aging, a catalyst slurry is obtained. The solid in the slurry is separated, washed, dried, and calcined to obtain the original catalyst powder. This catalyst is suitable for any type of reactor, including slurry bed reactors, fluidized bed reactors, and fixed bed reactors.

[0024] Compared with existing technologies, the copper-silicon catalyst, its preparation method, and its application described in this invention have the following advantages: This invention presents a copper-silicon catalyst prepared by a stepwise precipitation method. This method features mild process conditions, a wide range of parameter control thresholds, and readily available and inexpensive catalyst support raw materials. Adding only a small amount of metal promoters effectively improves the catalyst's conversion rate, selectivity, and lifetime. Alkali metal and alkaline earth metal promoters effectively suppress the dehydration side reaction of the target product, improving product selectivity. The introduction of group VB to VIIB metal promoters reduces the size of copper particles and increases their dispersion on the silica support surface, effectively improving catalyst activity and the copper particles' resistance to sintering and agglomeration, thus extending catalyst lifetime. Even with a raw material containing a large amount of the target product, the catalyst maintains a selectivity of over 99% and a conversion rate of ≥98% after 1000 hours of operation, with a very high yield of 1-phenylethanol. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0026] The present invention will now be described in detail with reference to the embodiments.

[0027] A copper-silicon catalyst for the hydrogenation of acetophenone to 1-phenylethanol comprises the following components, based on the weight of the catalyst: The silica content is 43-79 wt%, the copper oxide content is 15-35 wt%, the additive A content is 3-10 wt%, and the additive B content is 3-12 wt%. Preferably, the silica content is 53-72 wt%, the copper oxide content is 20-30 wt%, the additive A content is 3-7 wt%, and the additive B content is 5-10 wt%.

[0028] Wherein, additive A is one or more of alkali metal or alkaline earth metal oxides, preferably potassium oxide, sodium oxide, calcium oxide or magnesium oxide, more preferably calcium oxide or magnesium oxide; additive B is one or more of group VB to VIIB metal oxides, preferably vanadium pentoxide, niobium pentoxide, tantalum pentoxide, molybdenum trioxide, tungsten trioxide and manganese dioxide, more preferably niobium pentoxide and tantalum pentoxide.

[0029] A method for preparing a copper-silicon catalyst for the hydrogenation of acetophenone to 1-phenylethanol includes the following steps: (1) First, powdered silica is uniformly dispersed in deionized water to form a suspension, and precipitant solution I is prepared at the same time.

[0030] (2) Next, the mixed salt solution of metals contained in additive A and additive B is added to the silica suspension in parallel with the precipitant solution I for the first step of co-precipitation. After aging at a certain temperature for a certain period of time, the remaining salts are washed away and the solid is separated.

[0031] (3) Disperse the separated solids again in water to form a suspension, and at the same time prepare precipitant solution II.

[0032] (4) The copper salt solution and precipitant solution II are added to the above suspension in parallel to carry out the second step of co-precipitation. After aging at a certain temperature, the catalyst slurry is obtained.

[0033] (5) Separate the solids from the slurry, wash, dry and calcine to obtain the original catalyst powder.

[0034] In this invention, the powdered silica used in step (1) can be one or more of the following: opal powder, diatomaceous earth, precipitated silica, nano silica, powdered silica sol, and silica microspheres, with a particle size of 80-2000 mesh, preferably 100-800 mesh. As raw materials for silica carriers, the above-mentioned substances are widely available and inexpensive, and are more economical than commonly used raw materials such as fumed silica and silica sol.

[0035] In this invention, the precipitant solution I and precipitant solution II can be one or more of the aqueous solutions of sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, and ammonium carbonate. The precipitant solution I and precipitant solution II can be the same or different.

[0036] In this invention, the silica mass fraction in the suspension of step (1) is 10-20 wt%. At this point, the slurry can be fully agitated by the stirring equipment, which is beneficial for the uniform dispersion of silica in the precipitant solution. When the silica concentration increases, the viscosity of the slurry increases significantly, which is not conducive to the uniform dispersion of silica. The concentration of precipitant solution I is 0.1-2.0 mol / L, preferably 0.5-1.0 mol / L.

[0037] In this invention, the metal salts corresponding to A and B in step (2) should be soluble metal salts, wherein the metal salt of A is preferably a chloride salt and a nitrate salt, and most preferably calcium nitrate and magnesium nitrate; the metal salt of B is preferably niobium ammonium oxalate and vanadium oxysulfate. The concentration of the mixed salt solution is 5-15 wt%.

[0038] Alkali metal or alkaline earth metal oxides can neutralize the acidic sites on the surface of the silica support, effectively inhibiting the further dehydration of the target product 1-phenylethanol to styrene, thereby reducing the formation of the final byproduct ethylbenzene and greatly improving the selectivity of 1-phenylethanol. The introduction of group VB to VIIB metal oxides can effectively reduce the particle size of the generated copper particles and improve their dispersion on the silica surface, which is beneficial to improving the catalyst's conversion rate and selectivity.

[0039] In this invention, in step (2), the co-precipitation temperature is controlled at 30-60℃, preferably 40-50℃, the pH value is controlled at 8.0-10.0, preferably 8.0-9.0, and the co-precipitation time is 0.5-3h, preferably 1-2h; the aging temperature is 50-90℃, preferably 60-80℃, and the aging time is 1-4h, preferably 2-3h.

[0040] In this invention, the concentration of the suspension prepared from the coprecipitate in step (3) is 10-20 wt% to ensure thorough agitation by the stirring device. The concentration of the precipitant solution II is 0.1-2.0 mol / L, preferably 0.5-1.0 mol / L.

[0041] In this invention, the copper salt in step (4) can be one or more of copper sulfate, copper chloride, copper nitrate, and copper acetate, preferably copper nitrate and copper chloride, and the concentration of the copper salt solution is 10-15 wt%.

[0042] In this invention, in step (4), the co-precipitation temperature is controlled at 30-60℃, preferably 40-50℃, the pH value is controlled at 8.0-9.0, the co-precipitation time is 0.5-3h, preferably 1-2h; the aging temperature is 50-100℃, preferably 80-100℃, the aging time is 1-4h, preferably 2-3h.

[0043] In this invention, the washing method in step (5) adopts conventional operation methods and has no specific requirements. In some instances, it can be carried out by washing with water and centrifuging. The drying temperature in step (5) is 80-120℃, preferably 100-110℃, the drying time is 12-24h, preferably 16-20h, the calcination temperature is 400-800℃, preferably 450-750℃, and the calcination time is 2-8h, preferably 4-6h.

[0044] The catalyst obtained by the above preparation method is suitable for any type of reactor, such as a slurry bed reactor, a fluidized bed reactor, or a fixed bed reactor. The reaction temperature is typically 80-200℃, preferably 100-180℃, and the reaction pressure is typically 0.1-10MPa, preferably 1-5MPa. Too low a temperature and pressure will result in a lower reaction conversion rate, while too high a temperature and pressure will lead to a decrease in the selectivity of the target product.

[0045] Specifically, when using this catalyst in a fixed-bed reactor, a forming aid needs to be added to the catalyst powder to form tablets before use. The forming aid is graphite, added at a rate of 1-3 wt%. The formed catalyst is in the form of cylindrical tablets, 3-6 mm in diameter and 2-5 mm in height. Compared with catalysts of other shapes, cylindrical catalysts have good chemical and structural stability, high mechanical strength, high mass and heat transfer efficiency, and are convenient for loading and unloading.

[0046] The present invention also provides an application of the catalyst prepared by the above method in the fixed-bed hydrogenation of acetophenone to 1-phenylethanol: The catalyst prepared in this invention needs to be reduced before use.

[0047] In one embodiment, the reduction method of the catalyst includes: maintaining the volume hourly space velocity (VHSV) of the mixed gas of hydrogen and nitrogen at 300-900 h⁻¹. -1 The catalyst is pre-reduced for at least 1 hour by introducing a mixture of hydrogen and nitrogen containing no more than 10% H2 by volume. Then, the proportion of hydrogen in the hydrogen and nitrogen mixture is gradually increased, and the hot spot temperature of the catalyst bed is controlled to not exceed 220°C. Finally, the catalyst is reduced in a pure hydrogen atmosphere at 220°C for 3-6 hours to obtain an activated catalyst.

[0048] In a preferred embodiment, the obtained activated catalyst is used for the hydrogenation of acetophenone to 1-phenylethanol. Preferably, the hydrogenation reaction is carried out at a pressure of 1-3 MPa and a temperature of 120-180°C. The feedstock is the actual feedstock from the hydrogenation section of a commercial plant, with a composition of 45 wt% acetophenone, 30 wt% 1-phenylethanol, 21.5 wt% ethylbenzene, and 3.5 wt% styrene, and the acetophenone volume hourly space velocity is 0.4-1.0 h⁻¹. -1 .

[0049] The products were qualitatively analyzed using gas chromatography-mass spectrometry (GC-MS). The content of each component in the reaction products was analyzed using gas chromatography. The conversion rate and selectivity of the catalyst were calculated using the following formulas: Conversion rate = (moles of acetophenone consumed in the reaction / moles of acetophenone in the raw material) * 100% Selectivity = (moles of 1-phenylethanol produced / moles of acetophenone consumed) * 100%.

[0050] Example 1 The raw materials were prepared according to the catalyst mass percentage of 63% SiO2-25% CuO-5% CaO-7% Nb2O5, and the catalyst was then prepared. (1) Disperse 63 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0051] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0052] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0053] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0054] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0055] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0056] Catalyst activation: 10 grams of catalyst were loaded into a fixed-bed reactor. After leak testing with N2, the system was thoroughly purged with N2. After the system was heated, the cut-in volume hourly space velocity was set to 600 h⁻¹. -1 The catalyst was pre-reduced for 1 hour with a nitrogen-hydrogen mixture containing 5% hydrogen gas. Then, the proportion of hydrogen in the hydrogen-nitrogen mixture was gradually increased to 20%, 50%, and 100%, while controlling the hot spot temperature of the catalyst bed to not exceed 220°C. Finally, the catalyst was reduced for 4 hours in a pure hydrogen atmosphere at 220°C to obtain an activated catalyst.

[0057] Hydrogenation reaction of acetophenone: After the catalyst is activated, the acetophenone hydrogenation reaction can be initiated. The reaction pressure is 2 MPa, the reaction temperature is 150 °C, and the feedstock is the actual feedstock from the acetophenone hydrogenation section of a commercial plant. Its composition is 45 wt% acetophenone, 30 wt% 1-phenylethanol, 21.5 wt% ethylbenzene, and 3.5 wt% styrene. The liquid hourly space velocity (LHSV) of acetophenone is 0.7 h⁻¹. -1 After reacting for 240 hours, the liquid product was collected for chromatographic analysis, and the conversion rate and selectivity were calculated.

[0058] Calculations show that the catalyst achieves a 98.7% conversion rate of acetophenone and a 99.2% selectivity for 1-phenylethanol. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0059] Example 2 The raw materials were prepared according to the catalyst mass percentage of 65% SiO2-25% CuO-3% CaO-7% Nb2O5, and the catalyst was then prepared. (1) Disperse 65 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0060] (2) Dissolve 12.64 g of Ca(NO3)2·4H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0061] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0062] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0063] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0064] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0065] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0066] Calculations show that the catalyst achieves a 98.7% conversion rate of acetophenone and a 95.6% selectivity for 1-phenylethanol. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0067] Example 3 The raw materials were prepared according to the catalyst mass percentages of 61% SiO2-25% CuO-7% CaO-7% Nb2O5, and the catalyst was then prepared. (1) Disperse 61 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0068] (2) Dissolve 29.50 g of Ca(NO3)2·4H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0069] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0070] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0071] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0072] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0073] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0074] Calculations show that the catalyst achieves a 98.6% conversion rate of acetophenone and a 99.1% selectivity for 1-phenylethanol. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0075] Example 4 The raw materials were prepared according to the catalyst mass percentages of 65% SiO2-25% CuO-5% CaO-5% Nb2O5, and the catalyst was then prepared. (1) Disperse 65 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0076] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 12.74 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0077] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0078] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0079] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0080] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0081] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0082] Calculations show that the catalyst achieves a 92.8% conversion rate of acetophenone and a 97.5% selectivity for 1-phenylethanol. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0083] Example 5 The raw materials were prepared according to the catalyst mass percentage of 60% SiO2-25% CuO-5% CaO-10% Nb2O5, and the catalyst was then prepared. (1) Disperse 60 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0084] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 25.49 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0085] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0086] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0087] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0088] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0089] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0090] Calculations show that the catalyst achieves a 98.6% conversion rate of acetophenone, a 99.2% selectivity for 1-phenylethanol, and ethylbenzene as the main byproduct. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0091] Example 6 The raw materials were prepared according to the catalyst mass percentages of 73% SiO2-15% CuO-5% CaO-7% Nb2O5, and the catalyst was then prepared. 73 g of 150 mesh silica microspheres were uniformly dispersed in 500 g of water to obtain a silica suspension. Simultaneously, a 1 mol / L (NH4)2CO3 precipitant solution was prepared.

[0092] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0093] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0094] (4) Prepare a 10wt% copper nitrate solution by dissolving 45.38 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) under parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0095] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0096] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0097] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0098] Calculations show that the catalyst achieves a acetophenone conversion of 87.5% and a 1-phenylethanol selectivity of 99.0%. For ease of comparison, the conversion and selectivity are listed in Table 1.

[0099] Example 7 The raw materials were prepared according to the catalyst mass percentage of 68% SiO2-20% CuO-5% CaO-7% Nb2O5, and the catalyst was then prepared. (1) Disperse 68 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0100] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0101] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0102] (4) Prepare a 10wt% copper nitrate solution by dissolving 60.50 g of Cu(NO3)2·3H2O. Add the solution to the suspension in (3) along with the prepared (NH4)2CO3 precipitant solution. During the addition, control the temperature at 40-50℃ and the pH value at 8.0-9.0. The addition is completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0103] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0104] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0105] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0106] Calculations show that the catalyst achieves a 93.7% conversion rate of acetophenone, a 89.9% selectivity for 1-phenylethanol, and ethylbenzene as the main byproduct. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0107] Example 8 The raw materials were prepared according to the catalyst mass percentages of 58% SiO2-30% CuO-5% CaO-7% Nb2O5, and the catalyst was then prepared. (1) Disperse 58 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0108] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0109] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0110] (4) Prepare a 10wt% copper nitrate solution by dissolving 90.74 g of Cu(NO3)2·3H2O. Add the solution to the suspension in (3) dropwise along with the prepared (NH4)2CO3 precipitant solution. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0111] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0112] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0113] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0114] Calculations show that the catalyst achieves a 98.4% conversion rate of acetophenone and a 99.2% selectivity for 1-phenylethanol. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0115] Example 9 The raw materials were prepared according to the following catalyst mass percentages: 63% SiO2, 25% CuO, 5% MgO, and 7% Nb2O5, and the catalyst was then prepared: (1) Disperse 63 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0116] (2) Dissolve 32.05 g of Mg(NO3)2·6H2O and 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the above precipitant dropwise to the suspension in (1) in parallel stream. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0117] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0118] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0119] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0120] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0121] Example 10 The raw materials were prepared according to the catalyst mass percentages of 63% SiO2-25% CuO-5% CaO-7% V2O5, and the catalyst was then prepared. (1) Disperse 63 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0122] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O and 19.47 g of VOSO4·5H2O in a certain amount of deionized water to prepare a 10 wt% mixed salt solution. Then, add the solution of the precipitant above to the suspension in (1) dropwise in parallel. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. After that, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0123] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0124] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0125] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0126] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0127] Comparative Example 1 The raw materials were prepared according to the catalyst mass percentage of 70% SiO2-25% CuO-5% CaO, and the catalyst was then prepared. (1) Disperse 70 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0128] (2) Dissolve 21.07 g of Ca(NO3)2·4H2O in a certain amount of deionized water to prepare a 10 wt% solution. Then, add the solution to the suspension in (1) dropwise along with the above precipitant solution. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The addition is completed in 2 hours. Afterward, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0129] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0130] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0131] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0132] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0133] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0134] Calculations show that the catalyst achieves an acetophenone conversion of 87.7% and a 1-phenylethanol selectivity of 95.2%. For ease of comparison, the conversion and selectivity are listed in Table 1.

[0135] Comparative Example 2 The raw materials were prepared according to the catalyst mass percentage of 68% SiO2-25% CuO-7% Nb2O5, and the catalyst was then prepared. (1) Disperse 68 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0136] (2) Dissolve 17.84 g of (NH4)3·[NbO(C2O4)2] in a certain amount of deionized water to prepare a 10 wt% solution. Then, add the solution to the suspension in (1) dropwise along with the above precipitant solution. During the dropwise addition, the temperature is controlled at 40-50℃ and the pH value is controlled between 8.0 and 9.0. The dropwise addition is completed in 2 hours. Afterward, the temperature is raised to 70℃ and stirred continuously for 2 hours. The obtained solid is washed 3-4 times to remove excess salts.

[0137] (3) The solid obtained in the previous step is redispersed in 500g of deionized water to form a suspension, and at the same time a 1mol / L (NH4)2CO3 precipitant solution is prepared.

[0138] (4) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add this solution, along with the prepared (NH4)2CO3 precipitant solution, dropwise to the suspension in (3) in parallel flow. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition should be completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0139] (5) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0140] (6) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0141] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0142] Calculations show that the catalyst achieves a 98.2% conversion rate of acetophenone, a 89.7% selectivity for 1-phenylethanol, and ethylbenzene as the main byproduct. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0143] Comparative Example 3 The raw materials were prepared according to a catalyst mass percentage of 75% SiO2 and 25% CuO, and the catalyst was then prepared. (1) Disperse 75 g of 150 mesh silica microspheres evenly in 500 g of water to obtain a silica suspension. At the same time, prepare a 1 mol / L (NH4)2CO3 precipitant solution.

[0144] (2) Prepare a 10wt% copper nitrate solution by dissolving 75.62 g of Cu(NO3)2·3H2O. Add the solution to the suspension in (1) dropwise along with the prepared (NH4)2CO3 precipitant solution. During the dropwise addition, maintain the temperature at 40-50℃ and the pH value between 8.0 and 9.0. The addition is completed in 2 hours. Afterward, raise the temperature to 90℃ and continue stirring for aging for 2 hours.

[0145] (3) The solid obtained after the above reaction was washed four times with deionized water, dried at 100°C for 16 hours, and then calcined at 600°C for 4 hours to obtain the original catalyst powder.

[0146] (4) Add 3wt% graphite to the original catalyst powder, mix thoroughly, and granulate to obtain cylindrical catalyst particles with a diameter of φ4mm*4mm, which is the final shaped catalyst.

[0147] The catalyst activation conditions and hydrogenation reaction conditions were the same as in Example 1.

[0148] Calculations show that the catalyst achieves an acetophenone conversion rate of 85.2%, a 1-phenylethanol selectivity of 87.4%, and ethylbenzene as the main byproduct. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0149] Calculations show that the catalyst achieves a 91.4% conversion rate of acetophenone, a 83.8% selectivity for 1-phenylethanol, and ethylbenzene as the main byproduct. For ease of comparison, the conversion rates and selectivity are listed in Table 1.

[0150] Table 1 Catalyst composition, conversion and selectivity data Catalyst components (mass percentage) Conversion rate Selective Example 1 <![CDATA[63%SiO2-25%CuO-5%CaO-7%Nb2O5]]> 98.7% 99.2% Example 2 <![CDATA[65%SiO2-25%CuO-3%CaO-7%Nb2O5]]> 98.7% 95.6% Example 3 <![CDATA[61%SiO2-25%CuO-7%CaO-7%Nb2O5]]> 98.6% 99.1% Example 4 <![CDATA[65%SiO2-25%CuO-5%CaO-5%Nb2O5]]> 92.8% 97.5% Example 5 <![CDATA[60%SiO2-25%CuO-5%CaO-10%Nb2O5]]> 98.6% 99.2% Example 6 <![CDATA[73%SiO2-15%CuO-5%CaO-7%Nb2O5]]> 87.5% 99.0% Example 7 <![CDATA[68%SiO2-20%CuO-5%CaO-7%Nb2O5]]> 93.7% 89.9% Example 8 <![CDATA[58%SiO2-30%CuO-5%CaO-7%Nb2O5]]> 98.4% 99.2% Example 9 <![CDATA[63%SiO2-25%CuO-5%MgO-7%Nb2O5]]> 98.2% 99.0% Example 10 <![CDATA[63%SiO2-25%CuO-5%CaO-7%V2O5]]> 98.4% 98.8% Comparative Example 1 <![CDATA[70%SiO2-25%CuO-5%CaO]]> 87.7% 95.2% Comparative Example 2 <![CDATA[68%SiO2-25%CuO-7%Nb2O5]]> 98.2% 89.7% Comparative Example 3 <![CDATA[75%SiO2-25%CuO]]> 85.2% 87.4% The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A copper-silicon catalyst characterized by: comprises, by weight percentage, silica 43-79 wt%; copper oxide 15-35 wt%; adjuvant A 3-10 wt%; adjuvant B 3-12 wt%; adjuvant A comprises one or more of alkali metal or alkaline earth metal oxides; adjuvant B comprises one or more of group VB to VIIB metal oxides.

2. The copper-silicon catalyst of claim 1, wherein: comprises, by weight percentage, silica 53-72 wt%; copper oxide 20-30 wt%; adjuvant A 3-7 wt%; adjuvant B 5-10 wt%.

3. The copper-silicon catalyst of claim 1, wherein: adjuvant A is one or more of potassium oxide, sodium oxide, calcium oxide and magnesium oxide; preferably, adjuvant A is calcium oxide or magnesium oxide; adjuvant B is one or more of vanadium pentoxide, niobium pentoxide, tantalum pentoxide, molybdenum trioxide, tungsten trioxide and manganese dioxide; preferably, adjuvant B is niobium pentoxide or vanadium pentoxide.

4. A process for the preparation of a copper-silicon catalyst as claimed in any one of claims 1 to 3, characterized in that: comprises the following steps: S1: uniformly dispersing silica in deionized water to form a silica suspension, and preparing a precipitant solution I again; S2: mixing a metal salt solution of adjuvant A and a metal salt solution of adjuvant B to form a mixed salt solution, adding the mixed salt solution and the precipitant solution I prepared in step S1 to the silica suspension prepared in step S1, and separating a solid after post-treatment; S3: dispersing the solid separated in step S2 in deionized water to form a separated solid suspension, and preparing a precipitant solution II again; S4: preparing a copper salt solution from copper oxide, adding the copper salt solution and the precipitant solution II prepared in step S3 to the separated solid suspension obtained in step S3, and obtaining a copper-silicon catalyst after post-treatment.

5. A process for the preparation of a copper-silicon catalyst according to claim 4, characterized in that: The silica in step S1 is powder silica, and the particle size of the silica is 80-2000 mesh; and / or, the mass fraction of silica in the silica suspension in step S1 is 10-20 wt%; preferably, the powder silica is one or more of opal powder, diatomite, precipitated white carbon black, nano white carbon black, powder silica sol, and silica gel microspheres; preferably, the particle size of the silica is 100-800 mesh; and / or, the molar concentration of the precipitant solution I in step S1 is 0.1-2.0 mol / L, preferably, the molar concentration of the precipitant solution I is 0.5-1.0 mol / L; and / or, the precipitant solution I in step S1 and the precipitant solution II in step S3 are one or more of aqueous sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, and ammonium carbonate, and the precipitant solution I and the precipitant solution II are the same or different.

6. The method for preparing a copper-silicon catalyst according to claim 4, characterized in that: The metal salt of the metal salt solution of adjuvant A in step S2 is a soluble metal salt; the metal salt of the metal salt solution of adjuvant B in step S2 is a soluble metal salt; preferably, the metal salt of the metal salt solution of adjuvant A in step S2 is one or both of chloride salt and nitrate salt, more preferably, the metal salt of the metal salt solution of adjuvant A is one or both of calcium nitrate and magnesium nitrate; preferably, the metal salt of the metal salt solution of adjuvant B in step S2 is one or both of ammonium niobium oxalate and vanadyl sulfate; And / or, the mass concentration of the mixed salt solution in step S2 is 5-15wt%; And / or, the solid obtained after the separation in step S2 is obtained by co-precipitation, washing and centrifugation, and drying; And / or, the temperature of the co-precipitation is 30-60℃, preferably, the temperature is 40-50℃; And / or, the pH value of the co-precipitation is 8.0-10.0, preferably, the pH value is 8.0-9.0; And / or, the time of the co-precipitation is 0.5-3h, preferably, the time is 1-2h; And / or, the aging temperature is 50-90℃, preferably, the aging temperature is 60-80℃; And / or, the aging time is 1-4h, preferably, the aging time is 2-3h.

7. The method for preparing a copper-silicon catalyst according to claim 4, characterized in that: The mass concentration of the separated solid in the separated solid suspension in step S3 is 10-20wt%; the molar concentration of the precipitant solution II is 0.1-2.0 mol / L, preferably, the molar concentration of the precipitant solution II is 0.5-1.0 mol / L; And / or, the copper-silicon catalyst obtained after the post-treatment in step S4 is obtained by co-precipitation, aging for a certain time, obtaining a catalyst slurry, separating the solid in the slurry, washing, drying, and calcining to obtain the copper-silicon catalyst; And / or, the temperature of the co-precipitation is 30-60℃, preferably, the temperature of the co-precipitation is 40-50℃; And / or, the pH value of the co-precipitation is 8.0-9.0; And / or, the time of the co-precipitation is 0.5-3h, preferably, the time is 1-2h; And / or, the aging temperature is 50-100℃, preferably, the aging temperature is 80-100℃; And / or, the aging time is 1-4h, preferably, the aging time is 2-3h; And / or, the washing is water washing and centrifugation; And / or, the drying temperature is 80-120℃, preferably, the drying temperature is 100-110℃; And / or, the drying time is 12-24h, preferably, the drying time is 16-20h; And / or, the calcining temperature is 400-800℃, preferably, the calcining temperature is 450-750℃; And / or, the calcining time is 2-8h, preferably, the calcining time is 4-6h.

8. Use of a copper-silicon catalyst according to any one of claims 1 to 3 or of a copper-silicon catalyst prepared according to the process of any one of claims 4 to 7, characterized in that: The reactor suitable for the catalyst includes a slurry bed reactor, a fluidized bed reactor, and a fixed bed reactor; And / or, the reaction temperature suitable for the copper-silicon catalyst is 80-200℃, preferably, the reaction temperature is 100-180℃; And / or, the reaction pressure suitable for the copper-silicon catalyst is 0.1-10MPa, preferably, the reaction pressure is 1-5MPa; Preferably, the copper-silicon catalyst is used in a fixed bed reactor, and a forming aid is added to the copper-silicon catalyst to form tablets; The forming aid includes graphite, and the amount of graphite added is 1-3wt%, and the formed catalyst is a cylindrical tablet with a diameter of 3-6mm and a height of 2-5mm.

9. Use of a copper-silicon catalyst according to any one of claims 1 to 3 or of a copper-silicon catalyst prepared according to the process of any one of claims 4 to 7 in the reaction of acetophenone hydrogenation to 1-phenylethanol, characterized in that: The copper-silicon catalyst is reduced before being used in the reaction of preparing 1-phenylethanol by hydrogenation of acetophenone, and the reduction method of the copper-silicon catalyst comprises the following steps: pre-reducing the copper-silicon catalyst by passing a mixed gas of hydrogen and nitrogen, then gradually increasing the proportion of hydrogen in the mixed gas of hydrogen and nitrogen, controlling the hotspot temperature of the catalyst bed in the process to be not more than 220 DEG C, and finally reducing in a pure hydrogen atmosphere at 220 DEG C for 3-6 h to obtain an activated catalyst, and the obtained activated catalyst is used in the reaction of preparing 1-phenylethanol by hydrogenation of acetophenone.

10. Use according to claim 9, characterized in that: The reaction pressure of the hydrogenation reaction is 1-3 MPa, the reaction temperature is 120-180°C, the raw material includes 45 wt% acetophenone, 30 wt% 1-phenylethanol, 21.5 wt% ethylbenzene, 3.5 wt% styrene, the volume space velocity of acetophenone is 0.4-1.0 h -1 ; And / or, the mixed gas volume space velocity of hydrogen and nitrogen is 300-900h -1 ; And / or, the volume fraction of H2 in the mixed gas of hydrogen and nitrogen is not more than 10%. And / or, the pre-reduction lasts for at least 1 h.