Aldehyde hydrogenation catalyst and preparation method thereof

Abstract

The invention provides an aldehyde hydrogenation catalyst and a preparation method thereof, and the preparation method comprises the following steps: step 1, preparing an aluminum precursor, a part of zinc precursor and a solvent into a zinc-aluminum mixed solution, and carrying out heating treatment; step 2, preparing a precipitant solution from a precipitant, a template agent and a solvent, and carrying out heating treatment; step 3, mixing the zinc-aluminum mixed solution with part of the precipitant solution, controlling the pH value to be less than 7, and heating and precipitating; 4, preparing the copper precursor, the remaining zinc precursor and a solvent into a zinc-copper mixed solution, and performing heating treatment; step 5, mixing the zinc-copper mixed solution, the residual precipitant solution and the mixture obtained in the step 3, and controlling the pH value to be greater than 7; and 6, adding an organosilane hydrophobic modifier, heating, stirring, separating to obtain a solid phase, drying, and roasting to obtain the catalyst. According to the invention, the anti-vacuole ability of the aldehyde hydrogenation catalyst is improved by introducing hydrophobic organosilane. By regulating and controlling pH values of different precipitation steps, stable generation of aluminum salt precipitates is facilitated, and free aluminum ions are reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical catalysts, and particularly relates to an aldehyde hydrogenation catalyst and a preparation method thereof. Background Art

[0002] Currently, the catalysts used in gas-phase aldehyde hydrogenation are mainly copper-zinc (Cu-Zn) catalysts. In the Cu-Zn catalyst, copper serves as the active component, and ZnO acts as a carrier and a promoter. The Cu-Zn catalyst is generally prepared by the co-precipitation method, and the obtained metal oxide powder is formed into a cylindrical catalyst after being pressed into tablets. The preparation by the precipitation method results in the presence of hydroxyl groups on its surface, including hydroxyl groups on the surface of copper (Cu-OH), hydroxyl groups on the surface of ZnO (Zn-OH), hydroxyl groups on the surface of Al 2 O 3 hydroxyl groups on the surface (Al-OH) and hydroxyl groups on the surface of doped graphite carbon (C-OH). The surface hydroxyl sites of the solid catalyst make the surface of the catalyst hydrophilic, capable of adsorbing and activating water molecules in the surrounding environment or generated during the reaction process; all of these promote the occurrence of side reactions and reduce the selectivity of the target product. In addition, the presence of water molecules in the catalyst will affect the side pressure strength of the catalyst and affect the long-term use of the catalyst. Currently, the most commonly used method is to perform silanization treatment on the surface of the catalyst, which increases the surface hydrophobicity while shielding the surface hydroxyl sites that can catalyze side reactions.

[0003] However, the existing process for silanizing the catalyst is relatively complex, and at the same time, organic solvents need to be introduced for washing during the treatment process, making it difficult for industrialization.

[0004] Chinese Patent CN 114797993 B proposes a multi-step combined silanization modification treatment. First, a silanization reagent molecule with a large size is used for silanization treatment to make the surface of the solid catalyst highly hydrophobic; then a silanization reagent molecule with a small size is used for silanization treatment to fully shield the surface hydroxyl groups of the solid catalyst. The solid catalyst needs to be dispersed in an organic solvent, and after solvent washing, filtration, drying, and calcination, a modified solid catalyst is obtained. This process is relatively complex.

[0005] Chinese Patent CN 116832712 A discloses a method for hydrophobic modification of the surface hydroxyl groups of molecular sieves by a silanization reagent using the post-grafting method. This process requires dispersion in an organic solvent and simultaneous high-temperature reflux, and the process is relatively complex.

[0006] In summary, how to simplify the production process and use low-cost raw materials to hydrophobize the catalyst is an important direction to promote the industrialization of this technology. Summary of the Invention

[0007] The main object of the present invention is to provide a hydrophobic aldehyde hydrogenation catalyst and a preparation method thereof, so as to further improve the anti-bubble ability of the aldehyde hydrogenation catalyst in the prior art, thereby prolonging the service life of the catalyst.

[0008] To achieve the above object, the present invention provides a preparation method of an aldehyde hydrogenation catalyst, comprising the following steps:

[0009] Step 1, preparing a zinc-aluminum mixed solution by mixing an aluminum precursor, a part of a zinc precursor and a solvent, and performing heat treatment;

[0010] Step 2, preparing a precipitant solution by mixing a precipitant, a template agent and a solvent, and performing heat treatment;

[0011] Step 3, mixing the zinc-aluminum mixed solution obtained in Step 1 with a part of the precipitant solution, controlling the pH to be less than 7, and heating to perform precipitation;

[0012] Step 4, preparing a zinc-copper mixed solution by mixing a copper precursor, the remaining zinc precursor and a solvent, and performing heat treatment;

[0013] Step 5, mixing the zinc-copper mixed solution obtained in Step 4, the remaining precipitant solution with the mixture obtained in Step 3, and controlling the pH to be greater than 7;

[0014] Step 6, mixing the mixed solution obtained in Step 5 with a hydrophobic modifier, stirring and reacting for a certain time, heating, and separating to obtain a solid phase; then drying and calcining the solid phase to obtain an aldehyde hydrogenation catalyst, wherein the hydrophobic modifier is an organosilane.

[0015] In the preparation method of the aldehyde hydrogenation catalyst of the present invention, the solvent in Step 1, the solvent in Step 2 and the solvent in Step 4 are the same, and are a mixture of ethanol and water; in Step 3, the pH is controlled to be 6.5-6.8, and in Step 5, the pH is controlled to be 7.5-7.8.

[0016] In the preparation method of the aldehyde hydrogenation catalyst of the present invention, in the mixture of ethanol and water, the mass content of ethanol is 30-60%.

[0017] In the preparation method of the aldehyde hydrogenation catalyst of the present invention, the aluminum precursor is calculated as alumina, the zinc precursor is calculated as zinc oxide, the copper precursor is calculated as copper oxide, the organosilane is calculated as silicon, and the mass ratio of the aluminum precursor, the zinc precursor, the copper precursor and the organosilane is 0.5-5:25-80:15-52:1-20; the mass ratio of the part of the zinc precursor to the remaining zinc precursor is 0.05-0.12.

[0018] The preparation method of the aldehyde hydrogenation catalyst described in the present invention, wherein the aluminum precursor is a soluble salt of aluminum, the zinc precursor is a soluble salt of zinc, and the copper precursor is a soluble salt of copper; the method for separating the solid phase in step 6 is evaporation treatment until a gel is obtained.

[0019] The preparation method of the aldehyde hydrogenation catalyst described in the present invention, wherein after the calcination in step 5, there is further a step of mixing with graphite and tabletting to obtain the aldehyde hydrogenation catalyst.

[0020] The preparation method of the aldehyde hydrogenation catalyst described in the present invention, wherein the heating treatment temperature in step 1 is 80 - 90 °C, the heating treatment temperature in step 2 is 80 - 90 °C, the heating temperature in step 3 is 80 - 90 °C, the heating treatment temperature in step 4 is 80 - 90 °C, and the heating temperature in step 6 is 80 - 90 °C.

[0021] The preparation method of the aldehyde hydrogenation catalyst described in the present invention, wherein the precipitant is oxalic acid or oxalate, and the ratio of the amount of substance of the precipitant to the sum of the amounts of substance of the aluminum precursor, zinc precursor, and copper precursor is 1.1 - 1.5. The template agent is P123 or CTAB.

[0022] In order to achieve the above object, the present invention also provides an aldehyde hydrogenation catalyst obtained by the above preparation method.

[0023] The beneficial effects of the present invention:

[0024] By introducing hydrophobic group silicon in the catalyst preparation process, the present invention increases the hydrophobic property of the catalyst surface, and improves the anti-bubble ability and service life of the aldehyde hydrogenation catalyst.

[0025] By regulating the pH value of different precipitation steps, the present invention reduces the dissolution of aluminum salt precipitation, is conducive to the stable formation of aluminum salt precipitation, and reduces free aluminum ions. Specific embodiments

[0026] The technical solution of the present invention will be described in detail below. The following embodiments are implemented on the premise of the technical solution of the present invention, and the detailed implementation process is given. However, the protection scope of the present invention is not limited to the following embodiments. For the structures or experimental methods without specific conditions noted in the following embodiments, they are usually in accordance with conventional conditions.

[0027] The present invention provides a preparation method of an aldehyde hydrogenation catalyst, and this aldehyde hydrogenation catalyst can be used to catalyze the aldehyde hydrogenation reaction in the gas phase method.

[0028] The preparation method of the aldehyde hydrogenation catalyst of the present invention includes the following steps:

[0029] Step 1, prepare a zinc-aluminum mixed solution by mixing an aluminum precursor, a part of a zinc precursor, and a solvent, and perform a heating treatment;

[0030] Step 2: Prepare a precipitant solution by mixing a precipitant, a templating agent, and a solvent, and perform a heat treatment.

[0031] Step 3: Mix the zinc-aluminum mixed solution obtained in Step 1 with a part of the precipitant solution, control the pH to be less than 7, and heat for precipitation.

[0032] Step 4: Prepare a zinc-copper mixed solution by mixing a copper precursor, the remaining zinc precursor, and a solvent, and perform a heat treatment.

[0033] Step 5: Mix the zinc-copper mixed solution obtained in Step 4, the remaining precipitant solution, and the mixture obtained in Step 3, and control the pH to be greater than 7.

[0034] Step 6: Slowly add an organosilane hydrophobic modifier to the mixture in Step 5, stir and react for a certain time, heat, and separate to obtain a solid phase; then dry and calcine the solid phase to obtain an aldehyde hydrogenation catalyst.

[0035] In the present invention, by introducing a hydrophobic organosilane during the catalyst preparation process, the hydrophobic property of the catalyst surface is increased, and the anti-bubble ability and service life of the aldehyde hydrogenation catalyst are improved. Moreover, introducing an organosilane during the catalyst preparation process in the present invention can avoid the complex operation step of additional catalyst modification and avoid the operation of washing with an organic solvent during the modification process. At the same time, by regulating the pH value of different precipitation steps, the dissolution of the aluminum salt precipitate is reduced, which is beneficial to the stable formation of the aluminum salt precipitate and reduces free aluminum ions. When the catalyst of the present invention is used for aldehyde hydrogenation, it can inhibit the side reactions of aldol condensation and self-condensation of aldehydes, and exhibits good activity and selectivity in the high-temperature gas-phase hydrogenation of high-carbon aldehydes.

[0036] In the present invention, the aluminum precursor is, for example, a soluble salt of aluminum, the zinc precursor is, for example, a soluble salt of zinc, and the copper precursor is, for example, a soluble salt of copper. The present invention does not make a special limitation on "soluble", and it can be understood according to the general understanding of solubility in the art, that is, it can be basically completely dissolved in the solvent. In one embodiment, the aluminum precursor is aluminum nitrate, the zinc precursor is zinc nitrate, and the copper precursor is copper nitrate.

[0037] In the present invention, the solvents used in each step can be the same or different, and can be water, alcohols, or a mixture thereof, etc. In one embodiment, the solvents in Step 1, Step 2, and Step 4 are the same, and are a mixture of ethanol and water. In another embodiment, in the mixture of ethanol and water, the mass content of ethanol is 40-60%, and more preferably 50%.

[0038] In Step 1, an aluminum precursor, a part of a zinc precursor, and a solvent are formulated into a zinc-aluminum mixed solution. In one embodiment, the aluminum precursor is calculated as aluminum oxide, the zinc precursor is calculated as zinc oxide, and the mass ratio of the aluminum precursor to the zinc precursor is 0.5-5:30-80. In another embodiment, in the zinc-aluminum mixed solution, the molar concentration of the zinc precursor calculated as zinc is 0.33-3.3 mol / l, and the molar concentration of the aluminum precursor calculated as aluminum is 0.3-3 mol / l. In one embodiment, the temperature of the heat treatment in Step 1 is 80-90 °C.

[0039] Step 2 of the present invention is: formulating a precipitant solution by using a precipitant, a templating agent, and a solvent, and performing a heat treatment.

[0040] In one embodiment, the precipitant is oxalic acid or an oxalate, and the templating agent is a dispersant, such as P123 or CTAB. The complexing effect of oxalic acid or an oxalate facilitates the molecular-level mixing of copper oxalate, zinc oxalate, and aluminum oxalate, inhibits the aggregation of catalyst copper, thereby obtaining highly dispersed copper oxide crystals, forming a catalyst with a large specific surface area and a suitable pore distribution, and further enabling the prepared copper-zinc-aluminum catalyst to have high hydrogenation activity and high alkyl alcohol selectivity.

[0041] In one embodiment, in the precipitant solution of the present invention, the molar concentration of the precipitant is 0.77-1.02 mol / L, and the mass concentration of the templating agent is 11.1 g / L-29.1 g / L.

[0042] Step 3 of the present invention is: mixing the zinc-aluminum mixed solution obtained in Step 1 with a part of the precipitant solution, controlling the pH value to be less than 7, and heating to perform precipitation.

[0043] Step 3 of the present invention uses a part of the precipitant solution to precipitate zinc and aluminum. In one embodiment, the molar ratio of zinc and aluminum in the zinc-aluminum mixed solution to the precipitant in the part of the precipitant solution is 1.1-1.3. The zinc-aluminum mixed solution is mixed with the part of the precipitant solution, the pH is controlled to be less than 7, preferably 6.5-6.8, and heating precipitation is performed. Stirring can be carried out during the heating process. In one embodiment, the temperature of the heating precipitation is 80-90 °C.

[0044] Step 4 is: formulating a zinc-copper mixed solution by using a copper precursor, the remaining zinc precursor, and a solvent, and performing a heat treatment.

[0045] In one embodiment, the copper precursor is calculated as copper oxide, the zinc precursor is calculated as zinc oxide, and the mass ratio of the zinc precursor to the copper precursor is 30 - 80:20 - 50, and the mass ratio of a part of the zinc precursor to the remaining zinc precursor is 0.05 - 0.29. In another embodiment, for the zinc-copper mixed solution, the molar concentration of the zinc precursor calculated as zinc is 0.3 - 0.83 mol / L, and the molar concentration of the copper precursor calculated as copper is 0.22 - 0.65 mol / L. In one embodiment, the temperature of the heat treatment in step 4 is 80 - 90 °C.

[0046] Step 5 is: mixing the zinc-copper mixed solution obtained in step 4, the remaining precipitant solution, and the mixture obtained in step 3, and controlling the pH to be greater than 7.

[0047] In step 5 of the present invention, the precipitant solution is mainly used to precipitate the remaining zinc and copper. The zinc-copper mixed solution, the remaining precipitant solution, and the mixture obtained in step 3 are mixed, and the pH is controlled to be greater than 7, preferably 7.5 - 7.8.

[0048] In step 3 of the present invention, the dosage of the precipitant solution and the dosage of the precipitant solution in step 5 are adjusted according to the required pH value.

[0049] Step 6 is: slowly dripping an organosilane hydrophobic modifier into the mixture in step 5, stirring and reacting for a certain time, heating, and separating to obtain a solid phase; then drying and calcining the solid phase to obtain an aldehyde hydrogenation catalyst.

[0050] In one embodiment, the organosilane is methyl orthosilicate or ethyl orthosilicate.

[0051] In one embodiment, the temperature of the heat treatment in step 6 is 80 - 90 °C. After the heat treatment of the mixture, solid-liquid separation is carried out to obtain a solid phase, and then it is dried and calcined to obtain an aldehyde hydrogenation catalyst.

[0052] In another embodiment, the mixture after the heat treatment in step 6 is further subjected to an evaporation treatment to obtain a solid phase (i.e., a gel-like solid), and then it is dried and calcined to obtain an aldehyde hydrogenation catalyst. Among them, during the evaporation process, the condensate, that is, the mixed solution of ethanol and water, can be continuously collected and the condensate can be recycled. This method does not use separation steps such as filtration, can greatly improve the utilization rate of raw materials, effectively reduce the preparation cost of the catalyst, and reduce environmental pollution.

[0053] In one embodiment, in step 6, after calcination, there is further a step of mixing with graphite and tabletting to obtain an aldehyde hydrogenation catalyst. The present invention does not particularly limit the addition amount of graphite, which can be adjusted according to needs.

[0054] In one embodiment, in the aluminum precursor of the present invention, the amount is calculated as aluminum oxide, the zinc precursor is calculated as zinc oxide, the copper precursor is calculated as copper oxide, and the organosilane is calculated as silicon. In the preparation of the aldehyde hydrogenation catalyst of the present invention, the mass ratio of the aluminum precursor, zinc precursor, copper precursor and organosilane is 0.5-5:25-80:15-52:1-20, preferably 1.52-3.5:27.4-76.3:17.5-51.3:6.3-17.2.

[0055] In one embodiment, the drying temperature is, for example, 105-120 °C, the calcination is, for example, 360-400 °C, and the calcination time is, for example, 3-4 hours.

[0056] Thus, the present invention provides a method for preparing an aldehyde hydrogenation catalyst. First, a zinc-aluminum solution, a zinc-copper solution, and a precipitant solution are respectively prepared, and then zinc-aluminum and zinc-copper are precipitated step by step, and the pH value of different precipitation steps is strictly controlled to reduce the presence of free aluminum ions in the catalyst. The catalyst of the present invention is used in the gas-phase hydrogenation reaction of aldehydes, can inhibit the aldol condensation and self-condensation side reactions of aldehydes, and exhibits good activity and selectivity in the high-temperature gas-phase hydrogenation of high-carbon aldehydes. In the preparation process of the catalyst of the present invention, a hydrophobic group silicon is also introduced by grafting, which increases the hydrophobic property of the catalyst surface and improves the anti-bubble ability and service life of the aldehyde hydrogenation catalyst.

[0057] The aldehyde hydrogenation catalyst obtained by the above method of the present invention comprises the following substances in parts by weight: 17.5-51.3 parts by weight of copper oxide, preferably 20-50 parts by weight, zinc oxide - 80 parts by weight, preferably 30-76.3 parts by weight, 6-17.2 parts by weight of silicon oxide, preferably 6.3-15.5 parts by weight, 27.4 0.5-5 parts by weight of aluminum oxide, preferably 1.52-3.5 parts by weight. In one embodiment, it also includes 1-3 parts by weight of graphite.

[0058] The technical solution of the present invention will be further described in detail below through specific examples.

[0059] Evaluation and analysis method: Evaluate using a 200 ml fixed-bed hydrogenation evaluation device. The reduction conditions are: hydrogen reduction, reduction temperature 180-210 °C, reduction time 3 hours, and cool down with nitrogen after the reduction ends.

[0060] In the following examples and comparative examples, zinc nitrate, aluminum nitrate, and copper nitrate used are hydrates. Specifically, zinc nitrate is zinc nitrate hexahydrate, aluminum nitrate is aluminum nitrate nonahydrate, and copper nitrate is copper nitrate trihydrate.

[0061] Example 1

[0062] (1) Take ethanol (ethanol content ≥ 99%) and deionized water, and prepare a 2200 g ethanol-water mixed solution with an ethanol weight content of 50%.

[0063] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir.

[0064] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C.

[0065] (4) Add the zinc-aluminum mixed solution obtained in step (2) and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8.

[0066] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C.

[0067] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution into the reaction kettle in step (4) for co-precipitation in parallel, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8.

[0068] (7) Slowly add 30 g of methyl orthosilicate to the mixed solution in step (6), stir and react for 30 min, and control the temperature at 90 °C.

[0069] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, continue to evaporate to obtain a gel.

[0070] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 108 g of black powder, with a metal ion yield of 99.5%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CA-1.

[0071] Example 2

[0072] (1) Take 1000 g of the condensed and collected ethanol-water mixed solution (ethanol content 85%) and 250 g of ethanol solution (ethanol content ≥ 99%), add 950 g of deionized water to prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%.

[0073] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir.

[0074] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of the P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C.

[0075] (4) Add the zinc-aluminum mixed solution and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8.

[0076] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 237 g of zinc nitrate and 53 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C.

[0077] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution into the reaction kettle in step (4) for co-precipitation in parallel, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8.

[0078] (7) Slowly add 30 g of methyl orthosilicate to the mixed solution in step (6), stir and react for 30 min, and control the temperature at 90 °C.

[0079] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, continue to evaporate to obtain a gel.

[0080] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 88.2 g of black powder, with a metal ion yield of 99.6%, and then add a certain amount of graphite and press it into tablets to obtain the catalyst CA-2.

[0081] Example 3

[0082] (1) Take 777 g of the ethanol-water mixed solution collected by condensation (ethanol content 85%), add 1423 g of deionized water to prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 30%.

[0083] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 30% ethanol-water mixed solution in step (1) to prepare a 50 ml zinc-aluminum mixed solution, heat it to 80 °C, and stir.

[0084] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of the CTAB template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 80 °C.

[0085] (4) Add the zinc-aluminum mixed solution and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 80 °C, and control the pH at about 6.5 - 6.8.

[0086] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 247 g of zinc nitrate and 115 g of copper nitrate thereto to form a zinc-copper mixed solution, and preheat it to 80 °C;

[0087] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution in a co-current manner to the reaction kettle in step (4) for co-precipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0088] (7) Slowly add 32 g of methyl orthosilicate to the mixed solution in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0089] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into the collection tank, do not collect the remaining water, continue to evaporate to obtain a gel;

[0090] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 110.4 g of black powder, with a metal ion recovery rate of 99.5%, and then add a certain amount of graphite and press it into tablets to obtain catalyst CA-3.

[0091] Example 4

[0092] (1) Take 1000 g of the condensed and collected ethanol-water mixed solution (ethanol content 85%) and 250 g of ethanol solution (ethanol content ≥ 99%), add 950 g of deionized water, and prepare 2200 g of ethanol-water mixed solution with an ethanol weight content of 50%;

[0093] (2) Take 5 g of zinc nitrate and 56 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 150 ml of zinc-aluminum mixed solution, heat it to 90 °C, and stir;

[0094] (3) Take 900 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0095] (4) Add the zinc-aluminum mixed solution and the precipitation solution in a co-current manner to a reaction kettle with heat preservation and stirring, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8;

[0096] (5) Take 900 g of the ethanol-water mixed solution prepared in step (1), add 87 g of zinc nitrate and 156 g of copper nitrate thereto to form a zinc-copper mixed solution, and preheat it to 90 °C;

[0097] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution in a co-current manner to the reaction kettle in step (4) for co-precipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0098] (7) Slowly add 40 g of methyl orthosilicate to the mixture in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0099] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into the collection tank, do not collect the remaining water, and continue evaporation to obtain a gel;

[0100] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 89.9 g of black powder with a metal ion yield of 99.5%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CA-4.

[0101] Example 5

[0102] (1) Take 1000 g of the condensed and collected ethanol-water mixed solution (ethanol content 85%) and 250 g of ethanol solution (ethanol content ≥99%), add 950 g of deionized water, and prepare 2200 g of ethanol-water mixed solution with an ethanol weight content of 50%;

[0103] (2) Take 50 g of zinc nitrate and 5.6 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 105 ml of zinc-aluminum mixed solution, heat it to 90 °C, and stir;

[0104] (3) Take 950 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0105] (4) Add the zinc-aluminum mixed solution and the precipitation solution into the reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8;

[0106] (5) Take 950 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 76.6 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C;

[0107] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution into the reaction kettle in step (4) for coprecipitation in parallel, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0108] (7) Slowly add 40 g of methyl orthosilicate to the mixture in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0109] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into the collection tank, do not collect the remaining water, and continue evaporation to obtain a gel;

[0110] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 86.5 g of black powder with a metal ion yield of 99.5%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CA-5.

[0111] Example 6

[0112] (1) Take 1000 g of the ethanol-water mixed solution collected by condensation (ethanol content 85%) and 250 g of the ethanol solution (ethanol content ≥99%), add 950 g of deionized water, and prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%.

[0113] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir.

[0114] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of the P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C.

[0115] (4) Add the zinc-aluminum mixed solution and the precipitation solution to a reaction kettle with heat preservation and stirring in a co-current manner, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8.

[0116] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C.

[0117] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution to the reaction kettle in step (4) for co-precipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8.

[0118] (7) Slowly add 25 g of methyl orthosilicate to the mixture in step (6), stir and react for 30 min, and control the temperature at 90 °C.

[0119] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, continue to evaporate to obtain a gel.

[0120] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 95.2 g of black powder with a metal ion yield of 99.5%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CA-6.

[0121] Example 7

[0122] (1) Take 1000 g of the ethanol-water mixed solution collected by condensation (ethanol content 85%), 250 g of the ethanol solution (ethanol content ≥ 99%), and add 950 g of deionized water to prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%;

[0123] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir;

[0124] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of the P123 template agent and 196.4 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0125] (4) Add the zinc-aluminum mixed solution and the precipitation solution to the reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8;

[0126] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C;

[0127] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution to the reaction kettle in step (4) for coprecipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0128] (7) Slowly add 20 g of methyl orthosilicate to the mixture in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0129] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into the collection tank, do not collect the remaining water, continue to evaporate to obtain a gel;

[0130] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 83.7 g of black powder, with a metal ion yield of 99.3%, and then add a certain amount of graphite and press it into tablets to obtain the catalyst CA-7.

[0131] Example 8

[0132] (1) Take 1000 g of the ethanol-water mixed solution collected by condensation (ethanol content 85%), 250 g of the ethanol solution (ethanol content ≥ 99%), and add 950 g of deionized water to prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%;

[0133] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir.

[0134] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C.

[0135] (4) Add the zinc-aluminum mixed solution and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8.

[0136] (5) Take 1000 g of a certain amount of the ethanol-water mixed solution prepared in step (1), add 237 g of zinc nitrate and 43 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C.

[0137] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution into the reaction kettle in step (4) for coprecipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8.

[0138] (7) Slowly add 15 g of methyl orthosilicate to the mixture in step (6), stir and react for 30 min, and control the temperature at 90 °C.

[0139] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, continue to evaporate to obtain a gel.

[0140] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 93.5 g of black powder, with a metal ion yield of 99.1%, and then add a certain amount of graphite and press it into tablets to obtain catalyst CA-8.

[0141] Example 9

[0142] (1) Take 1000 g of the condensed and collected ethanol-water mixed solution (ethanol content 85%) and 250 g of ethanol solution (ethanol content ≥ 99%), add 950 g of deionized water to prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%.

[0143] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 95 °C, and stir.

[0144] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 95 °C;

[0145] (4) Add the zinc-aluminum mixed solution and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 95 °C, and control the pH at about 6.5 - 6.8;

[0146] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 100 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 95 °C;

[0147] (6) Add the zinc-copper mixed solution obtained in step (5) and the precipitation solution into the reaction kettle in step (4) for coprecipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0148] (7) Slowly add 30 g of methyl orthosilicate to the mixed solution in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0149] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, continue to evaporate to obtain a gel;

[0150] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 95.3 g of black powder, with a metal ion yield of 99.4%, and then add a certain amount of graphite and press it into tablets to obtain catalyst CA-9.

[0151] Example 10

[0152] (1) Take ethanol (ethanol content ≥ 99%) and deionized water, and prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%;

[0153] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare a 50 ml zinc-aluminum mixed solution, heat it to 90 °C, and stir;

[0154] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0155] (4) Add the zinc-aluminum mixed solution and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8;

[0156] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate thereto to form a zinc-copper mixed solution, and preheat it to 90 °C;

[0157] (6) Add the zinc-copper mixed solution and the precipitation solution in a concurrent flow to the reaction kettle in step (4) for coprecipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0158] (7) Slowly add 30 g of methyl orthosilicate to the mixed solution in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0159] (8) Filter and wash the solution obtained in step (7), dry it at 120 °C, and calcine it at 360 - 400 °C for 3 - 4 hours to obtain 94.8 g of black powder, with a metal ion yield of 94.9%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CA-10.

[0160] Example 11

[0161] (1) Take ethanol (ethanol content ≥ 99%) and deionized water, and prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%;

[0162] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir;

[0163] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0164] (4) Add the zinc-aluminum mixed solution and the precipitation solution in a concurrent flow to a reaction kettle with heat preservation and stirring, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8;

[0165] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate thereto to form a zinc-copper mixed solution, and preheat it to 90 °C;

[0166] (6) Add the zinc-copper mixed solution and the precipitation solution in a concurrent flow to the reaction kettle in step (4) for coprecipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0167] (7) Slowly add 41 g of tetraethyl orthosilicate to the mixed solution in step (6), stir and react for 30 min, and control the temperature at 90 °C;

[0168] (8) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into the collection tank, do not collect the remaining water, continue evaporation to obtain a gel;

[0169] (9) Dry the gel obtained in step (8), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 108 g of black powder with a metal ion yield of 99.4%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CA-11.

[0170] Comparative Example 1

[0171] This comparative example catalyst was prepared by the method of Chinese Patent CN 102350360B

[0172] Take 1000 ml of 1 mol / L copper nitrate solution, 1773 ml of 1 mol / L zinc nitrate solution and 23.6 ml of 1 mol / L aluminum nitrate solution and mix them. Co-precipitate the mixed solution and sodium carbonate solution in a precipitation tank with stirring, control the precipitation temperature at about 50 °C, the pH value is 6.8 during the process, the neutralization time is 30 minutes, the end-point pH value is 7.2, then stir and age at 50 °C - 60 °C for 30 min, and then wash, filter, dry and granulate. The dried particles are calcined at 360 °C for 2 h to obtain 271 g of black powder with a metal ion yield of 95%. Then press it into tablets to obtain catalyst sample CB-1.

[0173] Comparative Example 2

[0174] (1) Take 1000 g of the condensed and collected ethanol-water mixed solution (ethanol content 85%) and 250 g of ethanol solution (ethanol content ≥ 99%), add 950 g of deionized water to prepare 2200 g of ethanol-water mixed solution with an ethanol weight content of 50%;

[0175] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of zinc-aluminum mixed solution, heat it to 90 °C and stir;

[0176] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0177] (4) Add the zinc-aluminum mixed solution and the precipitation solution into a reaction kettle with heat preservation and stirring in parallel, control the neutralization temperature at 90 °C, and control the pH at about 6.5 - 6.8;

[0178] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate to it to prepare a zinc-copper mixed solution, and preheat it to 90 °C;

[0179] (6) The zinc-copper mixed solution and the precipitation solution are added to the reactor in step (4) for coprecipitation. The neutralization temperature is controlled at 90 °C, and the pH is controlled at about 6.5 - 6.8. The ethanol-water mixed solution evaporated is condensed and collected to 1100 g. The collected ethanol-water mixed solution is put into a collection tank, and the remaining water is not collected. Continue evaporation to obtain a gel.

[0180] (7) The gel obtained in step (6) is dried and calcined at 360 - 400 °C for 3 - 4 hours to obtain 79 g of black powder with a metal ion yield of 99.4%. Then, a certain amount of graphite is added and pressed into tablets to obtain the catalyst CB-2.

[0181] Comparative Example 3

[0182] The catalyst of this comparative example is prepared by the method of Chinese Patent CN1087971C

[0183] 95.6 g of copper nitrate and 235 g of zinc nitrate are formulated into a 2000 ml salt solution, and 170 g of oxalic acid is formulated into a 3000 ml precipitant solution. Its pH value is adjusted to 3.0, and then they are respectively added to two parallel elevated tanks and heated to 20 °C. When the low-position precipitation tank is heated to 20 °C in a water bath, start the stirrer. Under strong stirring, the two solutions are added to the precipitation tank in parallel within 30 minutes, and then aged for 0.5 hour under weak stirring. Then, the precipitate is discharged, filtered, and air-dried overnight to obtain a coprecipitate. It is dried at 110 °C for 8 hours, then heated from room temperature to 360 °C in 6 hours, and calcined at 360 °C for 4 hours to obtain the catalyst matrix, obtaining 69 g of black powder with a metal ion yield of 85%. Then, an appropriate amount of graphite is added, and after mixing evenly, it is pressed into tablets to obtain the catalyst CB-3.

[0184] Comparative Example 4

[0185] (1) Take ethanol (ethanol content ≥ 99%) and deionized water, and prepare a 2200 g ethanol-water mixed solution with an ethanol weight content of 50%.

[0186] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate and add them to the 50% ethanol-water mixed solution in step (1) to prepare a 50 ml zinc-aluminum mixed solution, and heat it to 90 °C and stir.

[0187] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C.

[0188] (4) The zinc-aluminum mixed solution and the precipitation solution are added to the reactor with heat preservation and stirring in parallel, controlling the neutralization temperature at 90 °C and the pH at about 6.5 - 6.8.

[0189] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate thereto to form a zinc-copper mixed solution, and preheat it to 90 °C;

[0190] (6) Add the zinc-copper mixed solution and the precipitation solution in a concurrent flow to the reaction kettle in step (4) for coprecipitation, control the temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0191] (7) Condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, and continue evaporation to obtain a gel;

[0192] (8) Dry the gel obtained in step (7), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 96 g of black powder with a metal ion yield of 99.4%, and then add a certain amount of graphite to press into tablets to obtain the catalyst CB-4.

[0193] Comparative Example 5

[0194] (1) Take 1000 g of the condensed and collected ethanol-water mixed solution (ethanol content 85%) and 250 g of ethanol solution (ethanol content ≥ 99%), add 950 g of deionized water, and prepare 2200 g of an ethanol-water mixed solution with an ethanol weight content of 50%;

[0195] (2) Take 10 g of zinc nitrate and 10 g of aluminum nitrate, add them to the 50% ethanol-water mixed solution in step (1) to prepare 50 ml of a zinc-aluminum mixed solution, heat it to 90 °C, and stir;

[0196] (3) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 15 g of P123 template agent and 216 g of ammonium oxalate to prepare an ammonium oxalate precipitation solution, and heat it to 90 °C;

[0197] (4) Add the zinc-aluminum mixed solution and the precipitation solution in a concurrent flow to a reaction kettle with heat preservation and stirring, control the neutralization temperature at 90 °C, and control the pH at about 7.5 - 7.8;

[0198] (5) Take 1000 g of the ethanol-water mixed solution prepared in step (1), add 210 g of zinc nitrate and 65 g of copper nitrate thereto to form a zinc-copper mixed solution, and preheat it to 90 °C;

[0199] (6) Add the zinc-copper mixed solution and the precipitation solution in a concurrent flow to the reaction kettle in step (4) for coprecipitation, control the neutralization temperature at 90 °C, control the pH at about 7.5 - 7.8, condense and collect the evaporated ethanol-water mixed solution to 1100 g, put the collected ethanol-water mixed solution into a collection tank, do not collect the remaining water, and continue evaporation to obtain a gel;

[0200] (7) Dry the gel obtained in step (6), calcine it at 360 - 400 °C for 3 - 4 hours to obtain 84.1 g of black powder with a metal ion yield of 99.2%. Then add a certain amount of graphite and press it into tablets to obtain catalyst CB-5.

[0201] The physical property indexes of the prepared catalysts are listed in Table 1.

[0202] Table 1 Physical property indexes of the catalysts

[0203] Catalyst <![CDATA[Specific surface area, m 2 / g]]> Pore volume, ml / g Average pore diameter, nm CA-1 56.6 0.35 16.7 CA-2 59.7 0.36 17.3 CA-3 60.6 0.39 17.6 CA-4 58.4 0.37 16.4 CA-5 55.3 0.36 16.9 CA-6 57.2 0.36 16.8 CA-7 56.5 0.38 16.9 CA-8 57.3 0.34 16.8 CA-9 56.2 0.35 16.6 CA-10 56.8 0.35 16.4 CA-11 56.7 0.36 16.7 CB-1 35.4 0.21 12.5 CB-2 39.8 0.29 13.6 CB-3 35.7 0.28 12.8 CB-4 52.6 0.31 14.6 CB-5 43.2 0.36 14.7

[0204] As shown in Table 1, the catalyst obtained by evaporation hydrolysis of copper-zinc-aluminum salt solution in the present invention has a large specific surface area, pore volume and pore diameter. The large specific surface area improves the dispersion of the active metal phase copper, and the large pore diameter is conducive to the diffusion of reactants inside the catalyst, realizing effective hydrogenation.

[0205] The results of the aldehyde hydrogenation catalysts in each example and comparative example used for catalyzing the hydrogenation of octenal are shown in Table 2.

[0206] Evaluate on a 200 ml fixed-bed hydrogenation evaluation device. The reduction conditions are: hydrogen reduction, reduction temperature 205 °C, reduction time 3 hours, and cool down with nitrogen after the reduction ends. The evaluation conditions are: the raw material is industrial octenal (purity > 95.5%), the feed temperature is 150 °C, the volume ratio of hydrogen to octenal is 8000:1, and the reaction space velocity is 0.35 h -1 , and the reaction pressure is 0.45 MPa.

[0207] Table 2 Results of the aldehyde hydrogenation catalysts in each example and comparative example used for catalyzing the hydrogenation of octenal

[0208] Catalyst Conversion rate of octenal, wt% Selectivity of octanol, % CA-1 99.99 99.74 CA-2 99.99 99.62 CA-3 99.99 99.78 CA-4 99.92 99.59 CA-5 99.99 99.49 CA-6 99.99 99.73 CA-7 99.99 99.64 CA-8 99.99 99.73 CA-9 99.99 99.56 CA-10 99.99 99.62 CA-11 99.99 99.73 CB-1 99.58 99.45 CB-2 99.74 99.43 CB-3 99.55 99.41 CB-4 99.98 99.68 CB-5 99.49 99.42

[0209] As shown in Table 2, the catalysts in the examples and comparative examples of the present invention are evaluated for their hydrogenation performance under the same raw material octenal and the same process conditions. The catalysts prepared by evaporation hydrolysis of copper-zinc-aluminum salts, oxalic acid or oxalates in the present invention have relatively high hydrogenation activity and selectivity. Comparing each example with Comparative Example 2 and Comparative Example 5, it can be seen that by adjusting the pH value of different precipitation steps, the hydrogenation selectivity of the catalyst can be improved.

[0210] The results of the catalysts in the examples and comparative examples used for catalyzing the hydrogenation of n-butanal are shown in Table 3.

[0211] Experimental process conditions: The raw material is industrial n-butanal (purity > 96%), the feed temperature is 130 °C, the volume ratio of hydrogen to butanal is 4000:1, and the reaction space velocity is 0.35 h -l , and the reaction pressure is 0.45 MPa.

[0212] Table 3 Results of the Catalysts in Examples and Comparative Examples for Catalyzing the Hydrogenation of n-Butyraldehyde

[0213] Catalyst Conversion rate of butyraldehyde, wt% Selectivity of butanol, % CA-1 99.99 99.94 CA-2 99.99 99.82 CA-3 99.99 99.98 CA-4 99.92 99.79 CA-5 99.99 99.29 CA-6 99.99 99.93 CA-7 99.99 99.84 CA-8 99.99 99.93 CA-9 99.99 99.76 CA-10 99.99 99.62 CA-11 99.99 99.93 CB-1 99.57 99.35 CB-2 99.51 99.33 CB-3 99.42 99.41 CB-4 99.96 99.77 CB-5 99.38 99.38

[0214] As shown in Table 3, the hydrogenation performance of the catalysts in the examples and comparative examples of the present invention was evaluated under the same raw material n-butyraldehyde and the same process conditions. The catalysts prepared by evaporation hydrolysis of copper-zinc-aluminum salts, oxalic acid or oxalates in the present invention have relatively high hydrogenation activity and selectivity.

[0215] The anti-bubble ability of the catalyst was tested by the following process: An octenal and water solution was prepared according to a mass ratio of 10:1. Each catalyst was added to the prepared solution and left at room temperature for 10 days. The soaked catalyst was taken out, dried at 150 °C, and the side pressure strength of the catalyst before and after soaking was measured. The results are shown in Table 4.

[0216] Table 4 Test Results of the Anti-bubble Ability of the Catalyst

[0217]

[0218]

[0219] As shown in Table 4, the catalysts in Comparative Examples 1-5 were not grafted with organosilane, and their anti-bubble ability was significantly weaker than that of the catalysts in the examples.

[0220] Certainly, the present invention may also have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes and deformations should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing an aldehyde hydrogenation catalyst, characterized in that: The steps include: Step 1, preparing a zinc-aluminum mixed solution with an aluminum precursor, a portion of a zinc precursor and a solvent, and performing a heating treatment; Step 2, preparing a precipitant solution with a precipitant, a template and a solvent, and heating the solution; Step 3, mixing the zinc-aluminum mixed solution obtained in step 1 with a portion of the precipitant solution, controlling the pH to be less than 7, and heating to perform precipitation; Step 4, preparing a zinc-copper mixed solution by mixing the copper precursor, the remaining zinc precursor and the solvent, and heating the solution; Step 5, mixing the zinc-copper mixed solution obtained in step 4, the remaining precipitant solution and the mixture obtained in step 3, and controlling the pH value to be greater than 7; Step 6, mixing the mixture of step 5 with a hydrophobic modifier, heating and stirring, separating to obtain a solid phase, drying and calcining to obtain an aldehyde hydrogenation catalyst, wherein the hydrophobic modifier is an organosilane.

2. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: The solvent in step 1, the solvent in step 2 and the solvent in step 4 are the same, which is a mixture of ethanol and water; the pH in step 3 is controlled to be 6.5-6.8, and the pH in step 5 is controlled to be 7.5-7.

8.

3. The method for preparing an aldehyde hydrogenation catalyst according to claim 2, characterized in that: In the mixture of ethanol and water, the mass content of ethanol is 30-60%.

4. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: The aluminum precursor is calculated as aluminum oxide, the zinc precursor is calculated as zinc oxide, the copper precursor is calculated as copper oxide, and the organosilane is calculated as silicon. The mass ratio of the aluminum precursor, the zinc precursor, the copper precursor and the organosilane is 0.5-5:25-80:15-52:1-20; the mass ratio of part of the zinc precursor to the remaining zinc precursor is 0.05-0.

12.

5. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: The aluminum precursor is a soluble salt of aluminum, the zinc precursor is a soluble salt of zinc, and the copper precursor is a soluble salt of copper.

6. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: The method of separating the solid phase in step 5 is to evaporate the solid phase until a gel is obtained.

7. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: Step 6: After calcination, the step further includes mixing with graphite and tableting to obtain an aldehyde hydrogenation catalyst.

8. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: The temperature of the heating treatment in step 1 is 80-90°C, the temperature of the heating treatment in step 2 is 80-90°C, the temperature of the heating in step 3 is 80-90°C, the temperature of the heating treatment in step 4 is 80-90°C, and the temperature of the heating in step 6 is 80-90°C.

9. The method for preparing an aldehyde hydrogenation catalyst according to claim 1, characterized in that: The precipitant is oxalic acid or oxalate, and the ratio of the amount of the precipitant to the sum of the amounts of the aluminum precursor, the zinc precursor and the copper precursor is 1.1 to 1.5; The template is P123 or CTAB.

10. The aldehyde hydrogenation catalyst obtained by the preparation method according to any one of claims 1 to 9.

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