Aldehyde hydrogenation catalyst as well as preparation method and application thereof
By preparing an aldehyde hydrogenation catalyst composed of alumina, nickel oxide, magnesium oxide, molybdenum trioxide, and yttrium trioxide, the problems of catalyst loss and by-product formation at high temperatures were solved, achieving a low-temperature and high-efficiency aldehyde hydrogenation reaction, improving the conversion rate and extending the catalyst life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-12
- Publication Date
- 2026-04-14
AI Technical Summary
Existing aldehyde hydrogenation catalysts are prone to loss at high temperatures, generating numerous byproducts, resulting in reduced catalyst activity, short service life, and sensitivity to water content, which affects the hydrogenation effect.
An aldehyde hydrogenation catalyst composed of alumina, nickel oxide, magnesium oxide, molybdenum trioxide, and yttrium trioxide was prepared by a one-pot method. The crystal size and dispersion of nickel were controlled, and the introduction of the auxiliary metal elements molybdenum and yttrium changed the electron density of the catalyst active sites, increased the adsorption of C=O, lowered the reaction temperature, and improved the conversion rate.
Improving the hydrogenation conversion rate of aldehydes under low-temperature conditions reduces the formation of by-products, extends the service life of catalysts, reduces energy consumption, lowers production costs, and prevents the loss of precious metals.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of aldehyde hydrogenation technology, specifically to an aldehyde hydrogenation catalyst, its preparation method, and its application. Background Technology
[0002] The hydrogenation reduction of aldehydes is an important type of reduction reaction in organic chemistry. Its core lies in the reaction of the aldehyde group (-CHO) with hydrogen in the presence of a catalyst, converting it into the corresponding primary alcohol (-CH2OH). This reaction is widely used in pharmaceutical synthesis, fragrance preparation, and fine chemicals, offering advantages such as high selectivity and mild reaction conditions. The reaction of aldehydes with hydrogen is usually carried out in the presence of certain metal catalysts. Commonly used catalysts include copper chromite, co-decoy compounds, nickel, copper, and mixtures of nickel and / or chromium; as well as some reducing copper oxide-zinc oxide mixtures. These catalysts exhibit lower-than-expected selectivity, resulting in excessive amounts of byproducts that affect the direct use of the alcohol, necessitating further purification before use.
[0003] Aldehyde hydrogenation processes are divided into gas-phase hydrogenation and liquid-phase hydrogenation. Gas-phase hydrogenation processes require excessively large reactors, and energy consumption increases accordingly when the boiling points of the reactants are high. Furthermore, the actual load often fails to meet design requirements. Liquid-phase hydrogenation, employing a low-temperature, high-pressure process, overcomes the shortcomings of gas-phase hydrogenation and is suitable for the production of higher alcohols. Summary of the Invention
[0004] The following technical problems exist in the existing technology:
[0005] (1) The reaction temperature is too high and the residence time of aldehyde in the catalyst is long during the hydrogenation of aldehyde, resulting in high energy consumption and easy loss of precious metals during high-temperature reaction, causing environmental pollution.
[0006] (2) High-temperature aldehydes are prone to generate aldehyde condensation polymers (including acetals, cyclic acetals, etc.) and long-chain esters, resulting in a large number of by-products and low yield; and tar adhering to the catalyst surface reduces the catalyst specific surface area, leading to reduced catalyst activity, shorter service life, and increased production costs.
[0007] (3) Existing catalysts have strict requirements on the water content in the feedstock. Excessive water content will reduce the activity of the catalyst and affect the hydrogenation effect.
[0008] The purpose of this invention is to overcome the problems existing in the prior art and provide an aldehyde hydrogenation catalyst, its preparation method, and its application. This aldehyde hydrogenation catalyst enables aldehydes to hydrogenate at low temperature (100-160℃) and high space velocity (1-6h). -1The hydrogenation process produces qualified alcohols, reducing production energy consumption and decreasing the formation of byproducts at low temperatures, thus increasing yield. It also reduces tar coverage on the catalyst surface, extending catalyst lifespan and preventing environmental pollution caused by precious metal loss. Furthermore, it increases electron transfer between the promoter yttrium and nickel, increasing the electron density of active sites and thereby increasing C=O adsorption and improving aldehyde hydrogenation conversion. Its mesoporous structure reduces hydrophilicity at high temperatures (100-150℃), facilitating reactant adsorption and enhancing catalytic activity.
[0009] To achieve the above objectives, a first aspect of the present invention provides an aldehyde hydrogenation catalyst comprising aluminum oxide, nickel oxide, magnesium oxide, molybdenum trioxide, yttrium trioxide, and optionally silicon dioxide, wherein, based on the total weight of the aldehyde hydrogenation catalyst, the content of aluminum oxide is 5-30 wt%, the content of nickel oxide is 50-75 wt%, the content of magnesium oxide is 0.1-15 wt%, the content of molybdenum trioxide is 0.1-5 wt%, the content of silicon dioxide is 0-12%, and the content of yttrium trioxide is 1-2 wt%.
[0010] Preferably, the alumina is γ-Al2O3.
[0011] A second aspect of the present invention provides a method for preparing an aldehyde hydrogenation catalyst, the method comprising the following steps:
[0012] (1) A dispersion containing nickel source, magnesium source, molybdenum source, yttrium source and optional silicon source and a precipitant are first mixed until the pH value is adjusted to 7-8. The solid phase is then separated from the mixture and then calcined to obtain powder.
[0013] (2) The pseudoboehmite and acid are mixed for a second time to obtain a sol;
[0014] (3) The powder obtained in step (1), the sol obtained in step (2) and the extrusion aid are mixed for the third time, and then extruded into strips and subjected to a second calcination.
[0015] Preferably, the method further includes preparing a dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and optionally a silicon source by mixing the nickel source, magnesium source, molybdenum source, yttrium source, water, and optionally a silicon source agent.
[0016] Preferably, the nickel source is at least one of nickel nitrate, nickel chloride, and nickel sulfate.
[0017] Preferably, the magnesium source is magnesium nitrate and / or magnesium chloride.
[0018] Preferably, the molybdenum source is at least one of ammonium molybdate, sodium molybdate, and molybdic acid.
[0019] Preferably, the silicon source is silica sol and / or water glass.
[0020] Preferably, the yttrium source is yttrium nitrate and / or yttrium chloride.
[0021] Preferably, in the dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and optionally a silicon source, the concentration of the nickel source is 0.2-0.4 g / mL.
[0022] Preferably, the mass ratio of the nickel source, the magnesium source, the molybdenum source, the silicon source and the yttrium source is 1:(0.08-0.2):(0.008-0.04):(0-0.3):(0.01-0.03).
[0023] Preferably, in step (1), the precipitant is at least one of sodium carbonate, potassium carbonate, sodium hydroxide and ammonium carbonate.
[0024] Preferably, in step (1), the conditions for the first mixing include: a temperature of 40-60°C, a time of 1-3 hours, and a stirring rate of 100-200 rpm.
[0025] Preferably, in step (1), the conditions for the first calcination include: a temperature of 400-700℃ and a time of 2.5-5h.
[0026] Preferably, in step (2), the acid is at least one of nitric acid, hydrochloric acid, and phosphoric acid.
[0027] Preferably, the mass ratio of the pseudoboehmite to the acid is 1:(0.01-0.03).
[0028] Preferably, the conditions for the second mixing include: a temperature of 20-40°C, a time of 1-1.5 h, and a stirring rate of 150-300 rpm.
[0029] Preferably, in step (3), the extrusion aid is at least one of guar gum powder, hydroxypropyl methylcellulose and polyethylene glycol.
[0030] Preferably, the mass ratio of the nickel source, the sol, and the extrusion aid is 1:(0.2-0.4):(0.009-0.08).
[0031] Preferably, in step (3), the conditions for the second calcination include: a temperature of 400-700℃ and a time of 2.5-5h.
[0032] A third aspect of the present invention provides an aldehyde hydrogenation catalyst prepared by the method described above.
[0033] The fourth aspect of the present invention provides the application of the above-described aldehyde hydrogenation catalyst in the hydrogenation of C6-C12 aldehydes.
[0034] Compared with the prior art, the present invention has the following technical effects:
[0035] (1) The present invention uses a one-pot method to prepare catalyst powder. The preparation process is simple and highly operable. It can also adjust the grain size and dispersion of nickel in the aldehyde hydrogenation catalyst, thereby increasing the electron density of the active sites, thereby increasing the adsorption of C=O and improving the aldehyde hydrogenation conversion rate.
[0036] (2) The present invention can suppress the interaction between nickel and aluminum oxide by introducing the auxiliary metal element molybdenum. Molybdenum can also provide oxygen holes, change the catalytic mechanism of nickel catalyst, and significantly improve the activity and selectivity of aldehyde hydrogenation reaction. The introduction of auxiliary metal yttrium changes the electron density of the active site of the catalyst, thereby increasing the adsorption of C=O and improving the conversion rate of aldehyde hydrogenation.
[0037] (3) The aldehyde hydrogenation catalyst described in this invention is used in the process of aldehyde hydrogenation. The reaction temperature is low and the space velocity is high. On the one hand, it can reduce the production of high-boiling products (including acetals, cyclic acetals, etc.) and long-chain esters by aldehyde condensation, increase the yield, and reduce the overall energy consumption. On the other hand, it reduces the specific surface area of the catalyst and the possibility of the active sites being covered, extends the service life of the catalyst, and reduces the production cost. Detailed Implementation
[0038] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.
[0039] The endpoints and any values of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.
[0040] The aldehyde hydrogenation catalyst of the present invention contains aluminum oxide, nickel oxide, magnesium oxide, silicon dioxide, molybdenum trioxide and yttrium trioxide, wherein, based on the total weight of the aldehyde hydrogenation catalyst, the content of aluminum oxide is 5-30 wt%, the content of nickel oxide is 50-75 wt%, the content of magnesium oxide is 0.1-15 wt%, the content of molybdenum trioxide is 0.1-5 wt%, the content of silicon dioxide is 0-12%, and the content of yttrium trioxide is 1-2 wt%.
[0041] According to the aldehyde hydrogenation catalyst of the present invention, the introduction of the auxiliary metal element molybdenum can suppress the interaction between nickel and alumina. Molybdenum can also provide oxygen holes, thereby changing the catalytic mechanism of nickel catalyst and significantly improving the activity and selectivity of aldehyde hydrogenation reaction. Furthermore, the introduction of the auxiliary metal yttrium changes the electron density of the active sites of the catalyst, thereby increasing the adsorption of C=O and improving the conversion rate of aldehyde hydrogenation. At the same time, it increases the interaction between each metal element and alumina, prolongs the service life of the catalyst, and avoids the loss of precious metals and environmental pollution.
[0042] In the aldehyde hydrogenation catalyst of the present invention, based on the total weight of the aldehyde hydrogenation catalyst, the content of alumina can be 5-30 wt%, preferably 7-27 wt%, more preferably 15-25 wt%; the content of nickel oxide can be 50-75 wt%, preferably 52-72 wt%, more preferably 55-70 wt%; the content of magnesium oxide can be 0.1-15 wt%, preferably 3-13 wt%, more preferably 3-6 wt%; the content of molybdenum trioxide can be 0.1-5 wt%, preferably 2-5 wt%, more preferably 3-4.5 wt%; the content of silicon dioxide can be 0-12%, preferably 8.7-10.6 wt%; and the content of yttrium trioxide can be 1-2 wt%, preferably 1.56-1.9 wt%.
[0043] In the aldehyde hydrogenation catalyst of this invention, the alumina can be γ-Al₂O₃. The specific surface area of the aldehyde hydrogenation catalyst can be 110-140 m². 2 / g, preferably 120-135m 2 / g. The average pore size of the aldehyde hydrogenation catalyst can be 7-9 nm, preferably 7.8-8.5 nm.
[0044] This invention also provides a method for preparing an aldehyde hydrogenation catalyst, the method comprising the following steps:
[0045] (1) A dispersion containing nickel source, magnesium source, molybdenum source, yttrium source and optional silicon source and a precipitant are first mixed until the pH value is adjusted to 7-8. The solid phase is then separated from the mixture and then calcined to obtain powder.
[0046] (2) The pseudoboehmite and acid are mixed for a second time to obtain a sol;
[0047] (3) The powder obtained in step (1), the sol obtained in step (2) and the extrusion aid are mixed for the third time, and then extruded into strips and subjected to a second calcination.
[0048] According to the method described in this invention, a catalyst powder is obtained by uniformly mixing water-soluble metal compounds in an aqueous solution and co-precipitating. This not only lowers the reduction temperature by increasing the nickel loading but also improves the surface nickel dispersion, thereby enhancing the interaction between nickel and alumina, reducing nickel loss, and improving the catalyst's reduction performance. Simultaneously, the introduction of promoters molybdenum and silicon provides oxygen vacancies, altering the catalytic mechanism of the nickel catalyst and significantly improving the activity and selectivity of the aldehyde hydrogenation reaction. The introduction of promoter yttrium alters the electron density of the catalyst's active sites, increasing C=O adsorption and improving the aldehyde hydrogenation conversion rate. Furthermore, it enhances the interaction between the various metal elements and alumina, extending the catalyst's service life.
[0049] In the method described in this invention, the method may further include preparing a dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and optionally a silicon source according to the following process: mixing the nickel source, magnesium source, molybdenum source, yttrium source, water, and optionally a silicon source. The conditions for mixing the nickel source, magnesium source, molybdenum source, yttrium source, water, and optionally a silicon source include: a temperature of 40-60°C, preferably 45-55°C; a time of 1-3 hours, preferably 1-2 hours; and a stirring rate of 100-200 rpm, preferably 150-200 rpm.
[0050] In the method described in this invention, the nickel source can be at least one of nickel nitrate, nickel chloride, and nickel sulfate, preferably nickel nitrate. The magnesium source can be magnesium nitrate and / or magnesium chloride, preferably magnesium nitrate. The molybdenum source can be at least one of ammonium molybdate, sodium molybdate, and molybdic acid, preferably ammonium molybdate. The silicon source can be silica sol and / or water glass, preferably silica sol. The yttrium source can be yttrium nitrate and / or yttrium chloride, preferably yttrium nitrate.
[0051] In the method described in this invention, in the dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and optionally a silicon source, the concentration of the nickel source can be 0.2-0.4 g / mL, preferably 0.2-0.32 g / mL.
[0052] In the method described in this invention, the amounts of the nickel source, the magnesium source, the molybdenum source, the silicon source, and the yttrium source are such that, based on the total weight of the aldehyde hydrogenation catalyst, the content of alumina is 5-30 wt%, the content of nickel oxide is 50-75 wt%, the content of magnesium oxide is 0.1-15 wt%, the content of molybdenum trioxide is 0.1-5 wt%, the content of silicon dioxide is 0-12%, and the content of yttrium trioxide is 1-2 wt%.
[0053] In a specific embodiment, the mass ratio of the nickel source, the magnesium source, the molybdenum source, the silicon source, and the yttrium source can be 1:(0.08-0.2):(0.008-0.04):(0-0.3):(0.01-0.03), preferably 1:(0.1-0.18):(0.008-0.01):(0.18-0.21):(0.0125-0.03).
[0054] In some embodiments, the method further includes preparing a dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and optionally a silicon source according to the following process: mixing nickel nitrate, magnesium nitrate, ammonium molybdate, silica sol, yttrium nitrate, and water; wherein, in the dispersion containing the nickel source, magnesium source, molybdenum source, yttrium source, and optionally a silicon source, the concentration of nickel nitrate is 0.2-0.4 g / mL, and the mass ratio of the amounts of nickel nitrate, magnesium nitrate, ammonium molybdate, silica sol, and yttrium nitrate is 1:(0.08-0.2):(0.008-0.04):(0-0.3):(0.01-0.03).
[0055] In the method described in this invention, in step (1), the precipitant can be at least one of sodium carbonate, potassium carbonate, sodium hydroxide, and ammonium carbonate, preferably sodium carbonate and / or sodium hydroxide. An appropriate amount of Na... + As a Lewis acid site, it can promote the adsorption of C=O bonds, thereby helping to improve the hydrogenation conversion rate of aldehydes.
[0056] In the method described in this invention, in step (1), the conditions for the first mixing include: a temperature of 40-60℃, preferably 45-55℃; a time of 1-3 hours, preferably 1-2 hours; and a stirring rate of 100-200 rpm, preferably 150-200 rpm. Co-precipitation is achieved through the first mixing, thereby adding different auxiliary metals to improve catalyst activity. The catalyst activity is controllable, has a long service life, and the aldehyde conversion rate can reach 99.99%, with a selectivity greater than 98%.
[0057] In the method described in this invention, the solid phase can be separated from the obtained mixture by filtration to obtain a filter cake. In step (1), the method further includes drying the solid phase obtained in step (1) before the first calcination. The drying conditions include: a temperature of 80-120°C, preferably 100-120°C; and a time of 5-10 hours, preferably 8-10 hours.
[0058] In the method described in this invention, in step (1), the conditions for the first calcination include: the temperature can be 400-700℃, preferably 450-650℃; the time can be 2.5-5h, preferably 3-4h.
[0059] In the method described in this invention, in step (2), the acid can be at least one of nitric acid, hydrochloric acid, and phosphoric acid, preferably nitric acid. The mass ratio of the boehmite to the acid can be 1:(0.01-0.03), preferably 1:(0.015-0.02. The concentration of the acid can be 40-60 wt%, preferably 40-55 wt%.
[0060] In the method described in this invention, the conditions for the second mixing include: the temperature can be 20-40℃, preferably 30-40℃; the time can be 1-1.5h, preferably 1.2-1.5h; and the stirring rate can be 150-300rpm, preferably 200-300rpm.
[0061] In the method described in this invention, in step (3), the extrusion aid can be at least one of guar gum powder, hydroxypropyl methylcellulose, and polyethylene glycol, preferably guar gum powder. The mass ratio of the nickel source, the sol, and the extrusion aid can be 1:(0.2-0.4):(0.009-0.08), preferably 1:(0.25-0.38):(0.01-0.02). The weight-average molecular weight of the polyethylene glycol can be 2000-6000.
[0062] In the method described in this invention, in step (3), the third mixing is used to prepare a plastic wet agglomerate from the powder obtained in step (1), the sol obtained in step (2), and the extrusion aid. The extrusion molding can be carried out using an extruder.
[0063] In the method described in this invention, step (3) may further include: drying the product obtained by the extrusion molding before the second calcination. The drying conditions include: a temperature of 80-120°C, preferably 100-120°C; and a time of 5-10 hours, preferably 8-10 hours.
[0064] In the method described in this invention, in step (3), the conditions for the second calcination include: the temperature can be 400-700℃, preferably 450-650℃; the time can be 2.5-5h, preferably 3-4h.
[0065] In some embodiments, the preparation method of the aldehyde hydrogenation catalyst of the present invention includes the following steps:
[0066] (1) A nickel source, a magnesium source, a molybdenum source, a yttrium source, water, and an optional silicon source are mixed at 40-60°C with a stirring rate of 100-200 rpm for 1-3 hours to obtain a dispersion. The dispersion and the precipitant are mixed at 40-60°C with a stirring rate of 100-200 rpm for 1-3 hours until the pH value is adjusted to 7-8. The solid phase is then separated from the mixture by filtration. The solid phase is dried at 80-120°C for 5-10 hours and then calcined at 400-700°C for 2.5-5 hours to obtain a powder.
[0067] (2) Mix boehmite and acid at 20-40℃ with a stirring rate of 150-300 rpm for 1-1.5 h to obtain a sol;
[0068] (3) Mix the powder obtained in step (1), the sol obtained in step (2) and the extrusion aid, then extrude the mixture into strips and dry it at 80-120℃ for 5-10h, and then calcine it at 400-700℃ for 2.5-5h.
[0069] The nickel source is at least one of nickel nitrate, nickel chloride, and nickel sulfate; the magnesium source is magnesium nitrate and / or magnesium chloride; the molybdenum source is at least one of ammonium molybdate, sodium molybdate, and molybdic acid; the silicon source is silica sol and / or water glass; and the yttrium source can be yttrium nitrate and / or yttrium chloride. In the dispersion, the concentration of the nickel source is 0.2-0.4 g / mL; and the mass ratio of the nickel source, magnesium source, molybdenum source, silicon source, and yttrium source is 1:(0.08-0.2):(0.008-0.04):(0-0.3): (0.01-0.03); the precipitant is at least one of sodium carbonate, potassium carbonate, sodium hydroxide and ammonium carbonate; the acid is at least one of nitric acid, hydrochloric acid and phosphoric acid, the mass ratio of the pseudoboehmite and the acid is 1:(0.01-0.03), and the concentration of the acid can be 40-60wt%; the extrusion aid is at least one of guar gum powder, hydroxypropyl methylcellulose and polyethylene glycol, and the mass ratio of the nickel source, the sol and the extrusion aid is 1:(0.2-0.4):(0.009-0.08).
[0070] In other embodiments, the preparation method of the aldehyde hydrogenation catalyst of the present invention includes the following steps:
[0071] (1) Nickel source, magnesium source, molybdenum source, silicon source, yttrium source and water are mixed at 45-55℃ and stirred at 150-200 rpm for 1-2 hours to obtain a dispersion. The dispersion and precipitant are mixed at 45-55℃ and stirred at 150-200 rpm for 1-2 hours until the pH value is adjusted to 7-8. The solid phase is then separated from the mixture by filtration. The solid phase is dried at 100-120℃ for 8-10 hours and then calcined at 450-650℃ for 3-4 hours to obtain a powder.
[0072] (2) Mix boehmite and acid at 30-40℃ with a stirring speed of 200-300 rpm for 1-1.5 h to obtain a sol;
[0073] (3) Mix the powder obtained in step (1), the sol obtained in step (2) and the extrusion aid, then extrude the mixture into strips and dry it at 100-120℃ for 8-10 hours, and then calcine it at 400-700℃ for 3-4 hours.
[0074] Wherein, the nickel source is nickel nitrate, the magnesium source is magnesium nitrate, the molybdenum source is ammonium molybdate, the silicon source is silica sol, and the yttrium source is yttrium nitrate; the precipitant is sodium carbonate and / or sodium hydroxide; in the dispersion, the concentration of the nickel source is 0.2-0.32 g / mL; the mass ratio of the nickel source, the magnesium source, the molybdenum source, the silicon source, and the yttrium source is 1:(0.1-0.18):(0.008-0.18). 01): (0.15-0.25): (0.0125-0.03); the acid is nitric acid; the mass ratio of the amount of boehmite to the amount of acid is 1: (0.015-0.02), and the concentration of the acid can be 40-55 wt%; the extrusion aid is guar gum powder, and the mass ratio of the amount of nickel source, the sol, and the extrusion aid is 1: (0.25-0.38): (0.01-0.02).
[0075] This invention also provides an aldehyde hydrogenation catalyst prepared by the above-described method. The aldehyde hydrogenation catalyst according to this invention is prepared by a precipitation method, which is simple. The catalyst activity is modified by adding magnesium, silicon, molybdenum, and yttrium promoters, resulting in controllable catalyst activity, a long service life, and an aldehyde conversion rate exceeding 98.8% with a selectivity greater than 95%.
[0076] In the aldehyde hydrogenation catalyst of the present invention, the length of the aldehyde hydrogenation catalyst can be 0.1-0.4 cm, preferably 0.2-0.3 cm.
[0077] This invention also provides the application of the above-mentioned aldehyde hydrogenation catalyst in the hydrogenation of C6-C12 aldehydes. According to the application described in this invention, the aldehyde hydrogenation catalyst of this invention exhibits a low reaction temperature and high space velocity during the hydrogenation of C6-C12 aldehydes. On the one hand, this reduces the formation of high-boiling products (including acetals, cyclic acetals, etc.) and long-chain esters from aldehyde polycondensation, increasing yield and reducing overall energy consumption. On the other hand, it reduces the catalyst's specific surface area and the possibility of active sites being covered, extending the catalyst's service life and reducing production costs. Furthermore, the catalyst activity can be controlled by adding magnesium, molybdenum, silicon, and yttrium promoters according to the ease of hydrogenation of the raw materials, thereby improving the service life, aldehyde conversion rate, and selectivity.
[0078] In the application described in this invention, the specific process of hydrogenating C6-C12 aldehydes may include: loading the aldehyde hydrogenation catalyst into a fixed-bed reactor, then carrying out a reduction reaction under a hydrogen atmosphere, followed by a hydrogenation reaction. The conditions for the reduction reaction include: a temperature of 400-600℃, preferably 450-500℃; a pressure of 0.5-3 MPa, preferably 2-3 MPa; and a time of 10-15 h, preferably 12-14 h. The conditions for the hydrogenation reaction include: a temperature of 80-150℃, preferably 100-150℃; a pressure of 2-5 MPa, preferably 3-4 MPa; and a space velocity of 2-6 h⁻¹. -1 Preferably 2-4h -1 In this document, the pressure referred to is gauge pressure. During the hydrogenation reaction, the volume ratio of hydrogen to the feedstock can be (400-500):1.
[0079] In the application described in this invention, the raw materials used may contain at least one of the C6-C12 aldehyde components, preferably decanal. The C6-C12 aldehyde component may also be a C6-C12 enal, preferably at least one of C6 enal, C8 enal, and C10 enal. The content of oxygen-containing compounds other than the C6-C12 aldehyde component in the raw materials used may be less than 0.5 wt%, preferably 0.2-0.4 wt%.
[0080] The following examples further illustrate the aldehyde hydrogenation catalyst, its preparation method, and its application according to the present invention. These examples are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following examples.
[0081] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available.
[0082] Example 1
[0083] (1) 140g nickel nitrate (hexahydrate), 14g magnesium nitrate, 5g ammonium molybdate, 3g silica sol, 3g yttrium nitrate and 500mL water were mixed at 50°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium carbonate at 50°C for 1h until the pH value was adjusted to 7.5. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0084] (2) Mix 30g of boehmite and 31g of 2wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0085] (3) The powder obtained in step (1), 35g of the sol obtained in step (2) and 4g of guar gum powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.2cm.
[0086] Example 2
[0087] (1) 100g nickel nitrate (hexahydrate), 18g magnesium nitrate, 0.8g ammonium molybdate, 2g silica sol, 3g yttrium nitrate and 500mL water were mixed at 40°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium hydroxide at 45°C for 1h until the pH value was adjusted to 7.5. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0088] (2) 40g of pseudoboehmite and 51g of 5wt% nitric acid were mixed at 30°C and stirred at 200rpm for 1.5h to obtain a sol;
[0089] (3) The powder obtained in step (1), 38g of the sol obtained in step (2) and 8g of guar powder are mixed, then extruded into strips and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.22cm.
[0090] Example 3
[0091] (1) 160g nickel nitrate (hexahydrate), 18g magnesium nitrate, 1.3g ammonium molybdate, 3g silica sol, 2g yttrium nitrate and 500mL water were mixed at 60°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium hydroxide at 60°C for 1h until the pH value was adjusted to 7.5. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0092] (2) Mix 55g of boehmite and 73g of 2wt% hydrochloric acid at 30°C with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0093] (3) The powder obtained in step (1), 35g of the sol obtained in step (2) and 2g of guar powder are mixed, then extruded and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.15cm.
[0094] Example 4
[0095] (1) 160g nickel nitrate (hexahydrate), 13g magnesium nitrate, 1.5g ammonium molybdate, 3g silica sol, 2g yttrium nitrate and 500mL water were mixed at 60°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium hydroxide at 60°C for 1h until the pH value was adjusted to 7.5. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0096] (2) Mix 50g of boehmite and 20g of 5wt% phosphoric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0097] (3) The powder obtained in step (1), 37g of the sol obtained in step (2) and 3g of guar powder are mixed, then extruded into strips and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.26cm.
[0098] Example 5
[0099] (1) 100g nickel nitrate (hexahydrate), 18g magnesium nitrate, 0.8g ammonium molybdate, 2g silica sol, 3g yttrium nitrate and 500mL water were mixed at 40°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with potassium carbonate at 40°C for 3h until the pH value was adjusted to 7. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 400°C for 5h to obtain a powder.
[0100] (2) Mix 40g of pseudoboehmite and 10g of 10wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0101] (3) The powder obtained in step (1), 40g of the sol obtained in step (2) and 8g of guar powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 400°C for 5h to obtain an aldehyde hydrogenation catalyst with a length of 0.3cm.
[0102] Example 6
[0103] (1) 200g nickel nitrate (hexahydrate), 40g magnesium nitrate, 8g ammonium molybdate, 6g yttrium nitrate and 500mL water were mixed at 60°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion and potassium carbonate were mixed at 60°C for 1h until the pH value was adjusted to 8. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 700°C for 2.5h to obtain a powder.
[0104] (2) Mix 40g of boehmite and 30g of 2wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0105] (3) The powder obtained in step (1), 40g of the sol obtained in step (2) and 1.8g of guar gum powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 700°C for 2.5h to obtain an aldehyde hydrogenation catalyst with a length of 0.23cm.
[0106] Comparative Example 1
[0107] (1) 140g nickel nitrate (hexahydrate), 14g copper nitrate, 5g ammonium molybdate, 3g silica sol, 3g yttrium nitrate and 500mL water were mixed at 50°C and stirred at 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium carbonate at 50°C for 1h until the pH value was adjusted to 7.5. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0108] (2) Mix 30g of boehmite and 31g of 2wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0109] (3) The powder obtained in step (1), 35g of the sol obtained in step (2) and 4g of guar gum powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.2cm.
[0110] Comparative Example 2
[0111] (1) 140g nickel nitrate (hexahydrate), 14g zinc nitrate, 5g ammonium molybdate, 3g silica sol, 3g yttrium nitrate and 500mL water were mixed at 50°C and stirred at 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium carbonate at 50°C for 1h until the pH value was adjusted to 7.5. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0112] (2) Mix 30g of boehmite and 31g of 2wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0113] (3) The powder obtained in step (1), 35g of the sol obtained in step (2) and 4g of guar gum powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.2cm.
[0114] Comparative Example 3
[0115] The aldehyde hydrogenation catalyst was prepared according to the method in Example 1, except that the pH value was adjusted to 2 in step (1). The specific steps are as follows:
[0116] (1) 140g nickel nitrate (hexahydrate), 14g magnesium nitrate, 5g ammonium molybdate, 3g silica sol, 3g yttrium nitrate and 500mL water were mixed at 50°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium carbonate at 50°C for 1h until the pH value was adjusted to 2. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0117] (2) Mix 30g of boehmite and 31g of 2wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0118] (3) The powder obtained in step (1), 35g of the sol obtained in step (2) and 4g of guar gum powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.24cm.
[0119] Comparative Example 4
[0120] The aldehyde hydrogenation catalyst was prepared according to the method of Example 1, except that the pH value was adjusted to 12 in step (1). The specific steps are as follows:
[0121] (1) 140g nickel nitrate (hexahydrate), 14g magnesium nitrate, 5g ammonium molybdate, 3g silica sol, 3g yttrium nitrate and 500mL water were mixed at 50°C with a stirring speed of 150rpm for 2h to obtain a dispersion. The dispersion was mixed with sodium carbonate at 50°C for 1h until the pH value was adjusted to 12. The solid phase was then separated from the mixture by filtration. The solid phase was dried at 100°C for 8h and then calcined at 450°C for 3h to obtain a powder.
[0122] (2) Mix 30g of boehmite and 31g of 2wt% nitric acid at 30℃ with a stirring speed of 200rpm for 1.5h to obtain a sol;
[0123] (3) The powder obtained in step (1), 35g of the sol obtained in step (2) and 4g of guar powder are mixed, and then extruded and dried at 100°C for 8h, and calcined at 450°C for 3h to obtain an aldehyde hydrogenation catalyst with a length of 0.25cm.
[0124] Test case
[0125] (1) The aldehyde hydrogenation catalysts obtained in Examples 1-6 were subjected to compositional analysis by X-ray fluorescence spectrometry (XRF). The test method was based on standard HG / T 6150-2023, and the results are recorded in Table 1.
[0126] (2) The aldehyde hydrogenation catalysts obtained in Examples 1-6 and Comparative Examples 1-4 were tested for specific surface area and average pore size by nitrogen adsorption method (BET). The test method refers to the national standard GB / T 38691-2020 and the results are recorded in Table 2.
[0127] (3) The aldehyde hydrogenation performance of the aldehyde hydrogenation catalysts obtained in Examples 1-6 and Comparative Examples 1-4 was tested. The specific steps are as follows: The aldehyde hydrogenation catalysts were respectively loaded into a fixed-bed reactor, and then a reduction reaction was carried out for 12 h at a temperature of 500 °C and a pressure of 2 MPa under a hydrogen atmosphere. Then, the reaction was carried out at a temperature of 100 °C and a pressure of 4 MPa with a space velocity of 3 h⁻¹. -1 (The volume ratio of hydrogen to decanal is 400:1) A hydrogenation reaction was carried out, and the product after the reaction was detected by chromatography. The conversion rate of decanal and the selectivity of decanol are recorded in Table 3.
[0128] (4) The aldehyde hydrogenation performance of the aldehyde hydrogenation catalysts obtained in Examples 1-6 and Comparative Examples 1-4 was tested. The specific steps are as follows: The aldehyde hydrogenation catalysts were loaded into fixed-bed reactors, and a reduction reaction was carried out for 12 hours at 500°C and 2 MPa under a hydrogen atmosphere. Then, the reaction was carried out at 120°C and 5 MPa with a space velocity of 3 h⁻¹. -1 (The volume ratio of hydrogen to decanal is 500:1) A hydrogenation reaction was carried out, and the product after the reaction was detected by chromatography. The conversion rate of decanal and the selectivity of decanol are recorded in Table 4.
[0129] (5) Stability test: The aldehyde hydrogenation catalyst obtained in Example 1 was loaded into a fixed-bed reactor, and a reduction reaction was carried out for 12 h at 500 °C and 2 MPa under a hydrogen atmosphere. Then, the reaction was carried out at 100 °C and 4 MPa with a space velocity of 3 h⁻¹. -1 The hydrogenation reaction was carried out (the volume ratio of hydrogen to decanal was 400:1) and repeated 6 times. After each hydrogenation reaction, the product was analyzed by chromatography, and the conversion rate of decanal and the selectivity of decanol were recorded in Table 5. The aldehyde hydrogenation catalyst obtained in Example 1 before and after the stability test was tested by nitrogen adsorption (BET). The specific surface area of the aldehyde hydrogenation catalyst obtained in Example 1 before the stability test was 133.34 m². 2 / g, the aldehyde hydrogenation catalyst obtained in Example 1 after stability testing has a strength of 133.33m. 2 / g.
[0130] Table 1
[0131]
[0132]
[0133] Table 2
[0134] serial number Specific surface area (m 2 / g) Average pore size (nm) Example 1 133.34 8.02 Example 2 128.67 8.34 Example 3 118.43 8.19 Example 4 120.62 7.84 Example 5 134.89 8.52 Example 6 130.27 8.50 Comparative Example 1 130.68 7.89 Comparative Example 2 129.64 8.14 Comparative Example 3 133.94 7.48 Comparative Example 4 129.56 7.52
[0135] Table 3
[0136]
[0137]
[0138] Table 4
[0139] serial number Decanal conversion rate (%) Decanol selectivity (%) Example 1 99.56 99.90 Example 2 99.34 99.00 Example 3 98.80 99.21 Example 4 98.89 98.91 Example 5 99.57 98.94 Example 6 99.85 98.87 Comparative Example 1 98.23 97.40 Comparative Example 2 97.45 97.33 Comparative Example 3 89.49 92.75 Comparative Example 4 92.66 91.53
[0140] Table 5
[0141]
[0142]
[0143] As can be seen from the results in Table 2, Examples 1-6 using the aldehyde hydrogenation catalyst described in this invention have high specific surface area and mesoporous structure.
[0144] As can be seen from the results in Tables 3 and 4, Examples 1-6 using the aldehyde hydrogenation catalyst described in this invention exhibit high decanal conversion and decanol selectivity.
[0145] As can be seen from the results in Table 5, Example 1 using the aldehyde hydrogenation catalyst described in this invention has a long service life, and the specific surface area does not decrease significantly after the aldehyde hydrogenation reaction.
[0146] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.
Claims
1. An aldehyde hydrogenation catalyst, characterized in that, The aldehyde hydrogenation catalyst contains aluminum oxide, nickel oxide, magnesium oxide, molybdenum trioxide, yttrium trioxide, and optionally silicon dioxide. Based on the total weight of the aldehyde hydrogenation catalyst, the aluminum oxide content is 5-30 wt%, the nickel oxide content is 50-75 wt%, the magnesium oxide content is 0.1-15 wt%, the molybdenum trioxide content is 0.1-5 wt%, the silicon dioxide content is 0-12 wt%, and the yttrium trioxide content is 1-2 wt%.
2. The aldehyde hydrogenation catalyst according to claim 1, characterized in that, The alumina is γ-Al2O3.
3. A method for preparing an aldehyde hydrogenation catalyst, characterized in that, The method includes the following steps: (1) A dispersion containing nickel source, magnesium source, molybdenum source, yttrium source and optional silicon source and a precipitant are first mixed until the pH value is adjusted to 7-8. The solid phase is then separated from the mixture and then calcined to obtain powder. (2) The pseudoboehmite and acid are mixed for a second time to obtain a sol; (3) The powder obtained in step (1), the sol obtained in step (2) and the extrusion aid are mixed for the third time, and then extruded into strips and subjected to a second calcination.
4. The method according to claim 3, characterized in that, The method further includes preparing a dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and an optional silicon source according to the following process: mixing the nickel source, magnesium source, molybdenum source, yttrium source, water, and an optional silicon source; Preferably, the nickel source is at least one selected from nickel nitrate, nickel chloride, and nickel sulfate; Preferably, the magnesium source is magnesium nitrate and / or magnesium chloride; Preferably, the molybdenum source is at least one selected from ammonium molybdate, sodium molybdate, and molybdic acid; Preferably, the silicon source is silica sol and / or water glass; Preferably, the yttrium source is yttrium nitrate and / or yttrium chloride; Preferably, in the dispersion containing a nickel source, a magnesium source, a molybdenum source, a yttrium source, and optionally a silicon source, the concentration of the nickel source is 0.2-0.4 g / mL; Preferably, the mass ratio of the nickel source, the magnesium source, the molybdenum source, the silicon source and the yttrium source is 1:(0.08-0.2):(0.008-0.04):(0-0.3):(0.01-0.03).
5. The method according to claim 3 or 4, characterized in that, In step (1), the precipitant is at least one of sodium carbonate, potassium carbonate, sodium hydroxide and ammonium carbonate.
6. The method according to any one of claims 3-5, characterized in that, In step (1), the conditions for the first mixing include: a temperature of 40-60℃, a time of 1-3h, and a stirring rate of 100-200rpm.
7. The method according to any one of claims 3-6, characterized in that, In step (1), the conditions for the first calcination include: a temperature of 400-700℃ and a time of 2.5-5h.
8. The method according to any one of claims 3-7, characterized in that, In step (2), the acid is at least one of nitric acid, hydrochloric acid, and phosphoric acid; Preferably, the mass ratio of the pseudoboehmite to the acid is 1:(0.01-0.03); Preferably, the conditions for the second mixing include: a temperature of 20-40°C, a time of 1-1.5 h, and a stirring rate of 150-300 rpm.
9. The method according to any one of claims 3-8, characterized in that, In step (3), the extrusion aid is at least one of guar gum powder, hydroxypropyl methylcellulose, and polyethylene glycol; Preferably, the mass ratio of the nickel source, the sol, and the extrusion aid is 1:(0.2-0.4):(0.009-0.08).
10. The method according to any one of claims 3-9, characterized in that, In step (3), the conditions for the second calcination include: a temperature of 400-700℃ and a time of 2.5-5h.
11. An aldehyde hydrogenation catalyst prepared by the method according to any one of claims 3-10.
12. The use of the aldehyde hydrogenation catalyst according to any one of claims 1, 2 and 11 in the hydrogenation of C6-C12 aldehydes.