Preparation method of bimetallic molecular sieve catalyst and application thereof in olefin hydroformylation / hydrogenation

Abstract

The application provides a bimetallic molecular sieve catalyst Co-M@MFI, and a preparation method thereof, which comprises the following steps: (1) dissolving metal precursors in water to obtain a metal salt solution; (2) adding a complex amine into the metal salt solution to obtain a complex solution; (3) adding an organic template into water, and then adding the complex solution to obtain a mixed solution; (4) adding a silicon source and an aluminum source into the mixed solution to form a mixed gel by stirring; (5) crystallizing the mixed gel at high temperature to obtain a crude molecular sieve; and (6) washing, drying, calcining, shaping and re-calcining the crude molecular sieve to obtain the bimetallic molecular sieve catalyst Co-M@MFI. In the application of the bimetallic molecular sieve catalyst Co-M@MFI in catalyzing the hydroformylation / hydrogenation reaction of olefins to generate alcohol, the coupling of the hydroformylation and the hydrogenation reaction is realized, the loss of active metal can be obviously avoided, excellent alcohol selectivity is achieved, and separation from products after the reaction is easy.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of bimetallic molecular sieve catalyst and its application, especially a kind of bimetallic molecular sieve catalyst and application in olefin hydroformylation / hydrogenation. BACKGROUND

[0002] Linear alcohol is widely used in the chemical industry in the fields of solvent, additive, plasticizer, lubricating oil, detergent, etc. At present, linear alcohol in industry is obtained by two-step series reaction: terminal olefin hydroformylation to obtain aldehyde, aldehyde separation and purification to obtain normal aldehyde, and selective hydrogenation of normal aldehyde to obtain linear alcohol. The two-step series method has problems such as complex device process, high energy consumption, etc. One-pot method realizes hydroformylation / hydrogenation series reaction, and directly selectively converts terminal olefin to linear alcohol, which is an ideal process for generating linear alcohol.

[0003] The key to one-pot method for preparing linear alcohol by hydroformylation / hydrogenation series reaction lies in constructing an effective catalyst. For hydroformylation / hydrogenation series reaction, the catalysts used mainly include various coordination complexes of Co, Rh, Ru, Pd and other metals. However, there is still a lot of room for improvement in terms of regulating the selectivity of linear alcohol, alkane selectivity, and long-term stable use of the catalyst, etc. SUMMARY

[0004] The purpose of the present application is to provide a preparation method of a bimetallic molecular sieve catalyst, a bimetallic molecular sieve catalyst prepared by the method and its application in olefin hydroformylation / hydrogenation. The catalyst preparation method is simple, can effectively generate linear alcohol in catalytic reaction, and has excellent catalyst stability.

[0005] In order to achieve the above-mentioned purpose, the technical solutions of the present application are as follows:

[0006] Firstly, a preparation method of a bimetallic molecular sieve catalyst is provided, which comprises the following steps:

[0007] (1) Dissolving a cobalt-containing compound and a M-containing compound in water to obtain a metal salt solution containing cobalt and M metal components, M = Zn, Mg, Mo or Ce one or more;

[0008] (2) Weighing a certain amount of complex amine into the aqueous solution of (1), stirring and mixing at room temperature to obtain a bimetallic complex amine solution;

[0009] (3) Weighing a certain amount of organic template into water, stirring and mixing at room temperature, then adding the metal complex amine solution obtained in step (2), and stirring for 0.5-6.0 h to obtain a mixed solution;

[0010] (4) Adding appropriate amount of silicon source and aluminum source to the mixed solution of step (3), and stirring at room temperature for 2-10 h to form a mixed gel;

[0011] (5) transferring the mixed gel of step (4) to a hydrothermal synthesis reactor, and obtaining a crude molecular sieve after high-temperature crystallization and growth;

[0012] (6) washing, drying, calcining, molding, and re-calcining the crude molecular sieve obtained in step (5) to obtain a bimetallic molecular sieve catalyst Co-M@MFI.

[0013] Preferably, the cobalt-containing compound in step (1) comprises one or more of cobalt nitrate, cobalt chloride, cobalt acetylacetonate, cobalt carbonyl, and hydrates thereof.

[0014] Preferably, the M-containing compound in step (1) comprises one or more of zinc nitrate hydrate, magnesium nitrate hydrate, ammonium molybdate, cerium nitrate hydrate.

[0015] Preferably, the mass ratio of M to Co is 0.5-15:1.

[0016] Preferably, in step (2), the complexing amine is one or more of ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, and ethylenediamine tetraacetate.

[0017] The molar ratio of the complexing amine to the sum of the cobalt-containing compound and the M-containing compound is 1-100:1, preferably 5-20:1, for example 5:1, 8:1, 10:1, etc.

[0018] Preferably, in step (3), the organic template agent is one or more of tetraethylammonium hydroxide and / or tetrapropylammonium hydroxide.

[0019] The molar ratio of the organic template agent to the sum of the cobalt-containing compound and the M-containing compound is 1-100:1, preferably 2-10:1, for example 2:1, 5:1, 10:1, etc.

[0020] Preferably, in step (4), the silicon source is at least one selected from silica gel, silica sol, and organosilicate, and the molar ratio of silicon in the silicon source to the sum of the cobalt-containing compound and the M-containing compound is 5-1000, preferably 5-10:1.

[0021] The aluminum source is at least one selected from sodium metaaluminate, sodium aluminate, variscite, gibbsite, aluminum isopropoxide, aluminum nitrate, and metallic aluminum solution.

[0022] The molar ratio between silicon in the silicon source and aluminum in the aluminum source is 20-100, preferably 40-60.

[0023] Preferably, in step (5), the conditions for high-temperature crystallization are a temperature of 80-200°C and a time of 1-8 days.

[0024] Preferably, the drying condition in step (6) is air atmosphere drying, temperature 50-150℃, time 6-48h; the calcination condition is air atmosphere calcination, temperature 300-800℃, time 4-24h; the calcination obtains the molecular sieve raw powder;

[0025] Preferably, the mass percentage of the Co element in the bimetallic molecular sieve raw powder Co-M@MFI is 0.02-10wt%, the mass percentage of the M element in the bimetallic molecular sieve catalyst Co-M@MFI is 0.05-20wt%, and the M is one or more of Zn, Mg, Mo or Ce;

[0026] Preferably, the forming treatment in step (6) is at least one of rolling forming, extrusion forming and tabletting forming, preferably rolling forming, and the rolling forming step includes:

[0027] (a) mixing a part of the molecular sieve raw powder with a binder according to the weight ratio of molecular sieve: binder = 1: (0.1-1.5), then adding an appropriate amount of auxiliary, and placing the mixture in a rotary drum forming machine for rolling forming to obtain first spherical particles with a diameter of 0.1-0.8mm;

[0028] (b) mixing a part of the molecular sieve raw powder with a binder according to the weight ratio of molecular sieve: binder = 1: (0.01-0.8) into the rotary drum forming machine of the first spherical particles in step (a), then adding an appropriate amount of auxiliary, and continuing to roll form the mixture on the basis of the first spherical particles to obtain second spherical particles with a diameter of 0.8-3.0mm;

[0029] (c) drying the second spherical particles obtained in step (b);

[0030] The weight ratio of the first part of the molecular sieve to the second part of the molecular sieve can be any ratio according to actual needs, and can also be adjusted at any time according to the situation of the molecular sieve ball forming, and the present application does not make special limitations.

[0031] Preferably, the operating condition of the rotary drum forming machine in step (a) and / or step (b) is that the inclination angle of the rotary drum is 30-60°, and the rotary drum rotating speed is 5-100rpm;

[0032] Preferably, the binder is water and / or silica sol; the purpose of adding the binder is to make the powder particles adhere to each other when rotating to improve the strength of the formed product. If the amount of the binder is insufficient, it is difficult to form a ball, and if the amount of the binder is excessive, the spherical product becomes soft and sticky. The silica sol can be an acidic silica sol or an alkaline silica sol, and the pH value of the alkaline silica sol is preferably 8.5 to 13.5, more preferably 9 to 12, and the sodium ion content is preferably 1 to 100 ppm, and the SiO2 content is preferably 15 to 40% by weight. Preferably, the adjuvant in step (a) and / or step (b) is one or more selected from the group consisting of sesbania powder, graphite, activated carbon, paraffin, stearic acid, glycerol, oxalic acid, tartaric acid, and citric acid. The amount of the adjuvant can be 0.1 to 10% by weight, preferably 0.1 to 5% by weight, based on the weight of the molecular sieve raw powder.

[0033] Preferably, the conditions of the re-baking treatment in step (6) are a temperature of 300 to 800°C and a time of 4 to 24 h.

[0034] Secondly, the present application discloses a bimetallic molecular sieve catalyst Co-M@MFI, which is prepared by the above method.

[0035] Thirdly, the present application discloses a method for catalyzing the hydroformylation / hydrogenation reaction of linear olefins by using the above bimetallic molecular sieve catalyst Co-M@MFI, wherein the method comprises reacting linear olefins with synthesis gas (CO and H2) under the action of the catalyst to generate alcohol.

[0036] In some specific embodiments, the hydroformylation / hydrogenation reaction can be carried out in a high-pressure reaction kettle. For example, linear olefins, the bimetallic molecular sieve catalyst Co-M@MFI and a reaction solvent are simultaneously added into a high-pressure reaction kettle, and carbon monoxide and hydrogen are filled into the high-pressure reaction kettle. The reaction temperature of the high-pressure reaction kettle is 60 to 200°C, the reaction time is 1 to 24 h, and the stirring rate is 100 to 1000 rpm.

[0037] Preferably, the linear olefins can be selected from one or more of C2 to C20 terminal olefin and internal olefin compounds, preferably C2 to C10 terminal olefin and internal olefin;

[0038] The molar ratio of the linear olefins to cobalt in the bimetallic molecular sieve catalyst Co-M@MFI is preferably 10 1 to 10 6 , more preferably 10 2 to 10 4 .

[0039] The reaction solvent can be one or more of toluene, tetrahydrofuran, ethyl acetate, tetraethylene glycol dimethyl ether, dodecane, acetonitrile;

[0040] The total pressure of carbon monoxide and hydrogen is preferably 0.5-10 MPa, more preferably 2-6 MPa; the hydrogen-carbon ratio (the pressure ratio of hydrogen and carbon monoxide) is preferably 0.2-5, more preferably 0.5-2.

[0041] The present application has the following advantages:

[0042] The bimetallic molecular sieve catalyst Co-M@MFI provided by the present application not only effectively realizes the olefin hydroformylation and aldehyde hydrogenation cascade reaction, and generates alcohol with high selectivity, but also has excellent catalyst stability, and the catalyst and product are easy to separate after reaction, which realizes one-pot cascade of hydroformylation and hydrogenation reaction, avoids the long process and high energy consumption problem of two-step catalytic reaction, avoids the cobalt loss problem of traditional heterogeneous cobalt-based catalyst, and has good industrial application prospect. DETAILED DESCRIPTION

[0043] The present application will be further described below by specific examples, and the examples described in the present application are only used to illustrate the present application, and do not limit the scope of the present application.

[0044] Unless otherwise specified, the raw materials used in the following specific embodiments of the present application are obtained by commercial means.

[0045] Unless otherwise specified, in the present application, the term "room temperature" refers to 20-40℃.

[0046] Example 1

[0047] First, a premixed solution of Co(NO3)2·6H2O, Mg(NO3)2·6H2O and ethylenediamine is prepared:

[0048] 6Kg of Co(NO3)2·6H2O and 9Kg of Mg(NO3)2·6H2O are weighed and dissolved in 100Kg of water to obtain a metal salt solution containing cobalt and magnesium; then, 27Kg of ethylenediamine is added and stirred at room temperature to obtain a cobalt-magnesium bimetallic complex amine solution.

[0049] Preparation of Co-Mg@MFI catalyst:

[0050] Weigh 130 Kg TPAOH (25% by weight) and 150 Kg water into the crystallization reactor for mixing, and stir the mixture at room temperature, with a stirring time of 0.5 h. Add the above complex amine solution 142 Kg, and continue stirring, with a stirring time of 0.5 h. Then, add 83.2 Kg tetraethyl orthosilicate (TEOS) and 0.5 Kg sodium metaaluminate to the solution, and stir at room temperature for another 6 h to form a mixed gel. Heat the gel to 170℃, and heat treat at 170℃ for 72 h. Finally, wash thoroughly with ethanol and water, dry in an oven at 100℃, and calcine in a muffle furnace at 550℃ for 6 h to remove the organic template, to obtain Co-Mg@MFI catalyst raw powder;

[0051] The BET specific surface area of the Co-Mg@MFI catalyst raw powder prepared in this example is 382 m 2 / gram.

[0052] Put 10 Kg of the prepared Co-Mg@MFI catalyst raw powder into a rotary table forming machine, with a rotary table diameter of 1.2 m, a rotary table depth of 450 mm, a rotary table inclination angle of 50°, and a rotary table speed of 20 rpm. Add 9 Kg of deionized water, and then add 0.5 Kg of Tianqin powder, and perform rolling forming to obtain first spherical particles with a diameter of 0.2-0.8 mm.

[0053] Mix 10 Kg of the Co-Mg@MFI catalyst raw powder with 5 Kg of basic silica sol with a SiO2 content of 40% by weight, and add to the rotary table forming machine of the first spherical particles, and then add 0.5 Kg of Tianqin powder. Continue rolling forming on the basis of the first spherical particles to obtain second spherical particles with a diameter of 0.8-3.0 mm.

[0054] Blow the obtained second spherical particles at 50℃, and supplement trace amounts of water multiple times, and tighten for 1 h, dry at 120℃ for 12 h, and then calcine at 550℃ for 6 h. Finally, obtain the spherical molecular sieve catalyst Co-Mg@MFI.

[0055] Example 2

[0056] This example is used to illustrate the preparation method of the bimetallic molecular sieve catalyst Co-Zn@MFI provided by the application.

[0057] First, prepare a premixed solution of Co(NO3)2·6H2O, Zn(NO3)2·6H2O and ethylenediamine:

[0058] Weigh 6Kg Co(NO3)2·6H2O, 8Kg Zn(NO3)2·6H2O, and dissolve them in 100Kg water to obtain a metal salt solution containing cobalt and zinc; then, add 27Kg ethylenediamine, and stir the mixture at room temperature to obtain a cobalt-zinc bimetallic complex amine solution.

[0059] Preparation of Co-Zn@MFI catalyst:

[0060] Weigh 130Kg TPAOH (25% by weight) and 150Kg water, and mix them in a crystallization reactor, and stir the mixture at room temperature for 0.5h, then add 141Kg of the complex amine solution, and continue to stir for 0.5h. Then, add 83.2Kg tetraethyl orthosilicate (TEOS) and 0.5Kg sodium metaaluminate to the solution, and stir the mixture at room temperature for another 6h to form a mixed gel. Heat the gel to 170℃, and heat treat it at 170℃ for 72h. Finally, wash it with ethanol and water, dry it in an oven at 100℃, and calcine it in a muffle furnace at 550℃ for 6h to remove the organic template to obtain Co-Zn@MFI catalyst powder;

[0061] The BET specific surface area of the Co-Zn@MFI catalyst powder prepared in this example is 378m 2 / gram.

[0062] Put 10Kg of the prepared Co-Zn@MFI catalyst powder into a rotary table forming machine, and use a rotary table with a diameter of 1.2m and a depth of 450mm, and set the inclination angle of the rotary table to 50°, and set the rotary speed of the rotary table to 20rpm. Add 9Kg of deionized water, and then add 0.5Kg of Tianjing powder, and perform rolling forming to obtain first spherical particles with a diameter of 0.2-0.8mm.

[0063] Mix 10Kg of the Co-Zn@MFI catalyst powder with 5Kg of alkaline silica sol with a SiO2 content of 40% by weight, and add them to the rotary table forming machine of the first spherical particles, and then add 0.5Kg of Tianjing powder, and continue to perform rolling forming on the basis of the first spherical particles to obtain second spherical particles with a diameter of 0.8-3.0mm.

[0064] Blow the obtained second spherical particles at 50℃, and supplement trace amount of water multiple times, and tighten for 1h, and dry them at 120℃ for 12h, and then calcine them at 550℃ for 6h. Finally, obtain the spherical molecular sieve catalyst Co-Zn@MFI.

[0065] Example 3

[0066] This example is used to illustrate the preparation method of the bimetallic molecular sieve catalyst Co-Ce@MFI provided by the application.

[0067] First, a premixed solution of Co(NO3)2·6H2O, Ce(NO3)2·6H2O and ethylenediamine was prepared:

[0068] 6Kg of Co(NO3)2·6H2O and 11Kg of Ce(NO3)2·6H2O were weighed and dissolved in 100Kg of water to obtain a metal salt solution containing cobalt and cerium; then, 27Kg of ethylenediamine was added and mixed under stirring at room temperature to obtain a cobalt and cerium bimetallic complex amine solution.

[0069] Preparation of Co-Ce@MFI catalyst:

[0070] 130Kg of TPAOH (25% by weight) and 150Kg of water were weighed and mixed in a crystallization reactor, and the mixture was stirred at room temperature for 0.5h, then 144Kg of the complex amine solution was added and stirring was continued for 0.5h. Subsequently, 83.2Kg of tetraethyl orthosilicate (TEOS) and 0.5Kg of sodium metaaluminate were added to the solution, and stirring was continued at room temperature for another 6h to form a mixed gel. The gel was heated to 150℃ and heat-treated at 150℃ for 72h. Finally, the gel was washed thoroughly with ethanol and water, dried in an oven at 120℃, and calcined in a muffle furnace at 500℃ for 16h to remove the organic template, thereby obtaining Co-Ce@MFI catalyst powder;

[0071] The BET specific surface area of the Co-Ce@MFI catalyst powder prepared in this example was 377m 2 / gram.

[0072] 10Kg of the prepared Co-Ce@MFI catalyst powder was placed in a rotary table forming machine, the rotary table diameter used for rotary forming was 1.2m, the rotary table depth was 450mm, the rotary table inclination was determined to be 50°, and the rotary table speed was set to 20rpm. 8Kg of deionized water was added, followed by the addition of 0.5Kg of Tianjing powder, and the mixture was subjected to rolling forming to obtain first spherical particles with a diameter of 0.2-0.8mm.

[0073] 10Kg of the Co-Ce@MFI catalyst powder and 5Kg of alkaline silica sol with a SiO2 content of 40% by weight were mixed and added to the rotary table forming machine of the first spherical particles, followed by the addition of 0.5Kg of Tianjing powder, and the mixture was subjected to rolling forming on the basis of the first spherical particles to obtain second spherical particles with a diameter of 0.8-3.0mm.

[0074] The second spherical particles obtained above were blown at 50℃ and supplemented with a small amount of water several times, and then tightened for 1h, dried at 120℃ for 12h, and finally calcined at 600℃ for 10h. Finally, the spherical molecular sieve catalyst Co-Ce@MFI was obtained.

[0075] Example 4

[0076] This example is used to illustrate the preparation method of the bimetallic molecular sieve catalyst Co-Mo@MFI provided by the present application.

[0077] First, a premixed solution of Co(NO3)2·6H2O, (NH4)6Mo7O 24 ·4H2O and ethylenediamine is prepared:

[0078] 6Kg of Co(NO3)2·6H2O and 29Kg of (NH4)6Mo7O 24 ·4H2O are weighed and dissolved in 100Kg of water to obtain a metal salt solution containing cobalt and molybdenum; then, 27Kg of ethylenediamine is added and mixed under stirring at room temperature to obtain a cobalt and molybdenum bimetallic complex amine solution.

[0079] Preparation of Co-Mo@MFI catalyst:

[0080] 130Kg of TPAOH (25% by weight) and 150Kg of water are weighed and mixed in a crystallization reactor, and the mixture is stirred at room temperature for 0.5h, then the complex amine solution is added and stirring is continued for 0.5h. After that, 83.2Kg of tetraethyl orthosilicate (TEOS) and 0.5Kg of sodium metaaluminate are added to the solution, and stirring is continued at room temperature for another 5h to form a mixed gel, which is heated to 120℃ and heat-treated at 120℃ for 72h. Finally, the gel is washed thoroughly with ethanol and water, dried in an oven at 100℃, and calcined in a muffle furnace at 650℃ for 6h to remove the organic template to obtain Co-Mo@MFI catalyst powder;

[0081] The BET specific surface area of the Co-Mo@MFI catalyst powder prepared in this example is 369m 2 / gram;

[0082] 10Kg of the prepared Co-Mo@MFI catalyst powder is placed in a rotary table forming machine, the rotary table used for rotary forming has a diameter of 1.2m, a depth of 450mm, and an inclination angle of 50°, and the rotary table rotates at a speed of 20rpm. 9Kg of deionized water is added, followed by 0.5Kg of Tianjing powder, and then rolling forming is carried out to obtain first spherical particles with a diameter of 0.2-0.8mm;

[0083] 10Kg of Co-Mo@MFI catalyst raw powder and 5Kg of basic silica sol with a SiO2 content of 40wt% were mixed and added to a first spherical particle rotary molding machine, then 0.5Kg of Tianqin powder was added, and the mixture was continuously rolled and molded on the basis of the first spherical particles to obtain second spherical particles with a diameter of 0.8-3.0mm.

[0084] The second spherical particles obtained above were blown at 50°C and supplemented with a small amount of water several times, and then tightened for 1 hour, dried at 120°C for 12 hours, and then calcined at 450°C for 16 hours. Finally, the spherical molecular sieve catalyst Co-Mo@MFI was obtained.

[0085] Test Examples

[0086] Application Example 1

[0087] This test example is used to illustrate the catalytic reaction results of the Co-Mg@MFI molecular sieve catalyst prepared in Example 1 in the propylene hydroformylation / hydrogenation reaction.

[0088] The following steps are included:

[0089] The linear olefin hydroformylation / hydrogenation reaction was carried out in a stainless steel high-pressure reaction kettle with a volume of 1L (mechanical stirring). The specific operation procedure was as follows: 5g of molded catalyst and 150mL of tetrahydrofuran were weighed and added to the reaction kettle, and the reactor was sealed. A mixture of hydrogen and carbon monoxide gas H2 / CO (v:v=1:1) at 0.5MPa was introduced into the reaction kettle and the reactor was fully replaced. 20g of the reactant propylene was weighed and added, and then a mixture of hydrogen and carbon monoxide gas H2 / CO (v:v=1:1) at 4.0MPa was charged. The stirring speed was set to 500rpm, the reaction temperature was set to 100°C, and the reaction time was set to 4h. After the reaction, the reaction products were analyzed and quantified by GC-MS.

[0090] Application Example 2

[0091] This application example provides an application of the Co-Zn@MFI molecular sieve catalyst prepared in Example 2 in the olefin hydroformylation / hydrogenation reaction, which is different from Application Example 1 in that the olefin compound used in Application Example 2 is 1-pentene, and the final product is a hexanal compound. The other steps and methods are the same as in Application Example 1 and will not be repeated here.

[0092] Application Example 3

[0093] The application example provides application of the Co-Ce@MFI molecular sieve catalyst prepared in Embodiment 3 in olefin hydroformylation / hydrogenation reaction, which is different from the application example 1 in that the olefin compound used in the application example 3 is 1-octene, and a nonyl aldehyde compound is finally obtained, and other steps and methods are the same as those in the application example 1, and details are not described herein.

[0094] Application Example 4

[0095] The application example provides application of the Co-Mo@MFI molecular sieve catalyst prepared in Embodiment 4 in olefin hydroformylation / hydrogenation reaction, which is different from the application example 1 in that the olefin compound used in the application example 4 is 1-decene, and a undecanal compound is finally obtained, and other steps and methods are the same as those in the application example 1, and details are not described herein.

[0096] The reaction product is quantitatively analyzed by using an Agilent 6890 gas chromatograph (hydrogen flame ionization detector, PEG20M capillary column, column length 50 m).

[0097] The content of the compounds such as alkanes, alkenes, aldehydes, alcohols and the like after the reaction is calculated by using area normalization method, and the solvent does not participate in integration.

[0098] Comparative Example 1

[0099] The comparative example is used to provide a preparation method of a cobalt-based catalyst Co / MFI for comparison.

[0100] TPAOH (25% by weight) and 150 g of water are weighed and mixed, and the mixture is stirred at room temperature, and the stirring time is set to 0.5 h. Then, 83.2 g of tetraethyl orthosilicate (TEOS) and 2.8 g of sodium metaaluminate are added to the solution, and the solution is stirred at room temperature for another 6 h to form a mixed gel. The gel is transferred to a 1000 mL stainless steel reaction kettle lined with polytetrafluoroethylene, and is heat-treated at 170 ℃ for 72 h. Finally, it is washed with ethanol and water, dried in an oven at 100 ℃, and calcined in a muffle furnace at 550 ℃ for 6 h to remove the organic template to obtain the MFI molecular sieve.

[0101] 2.3 g of Co(NO3)2·6H2O is weighed and dissolved in 50 g of deionized water to obtain a Co(NO3)2 solution. 23.0 g of the MFI molecular sieve carrier is immersed in the above solution, and stirred and mixed uniformly, and then dried in a 60 ℃ oven for 12 h to remove the solvent to obtain a powdery solid mixture. Then, the mixture is calcined in a muffle furnace at 500 ℃ for 7 h, and then reduced in a tube furnace in a pure H2 atmosphere (99%) at 400 ℃ for 6 h, and the hydrogen flow rate is 100 mL / min to obtain the catalyst Co / MFI. The reduced catalyst is used as a comparative cobalt-based catalyst.

[0102] Weigh 5 g of catalyst Co / MFI and 150 mL of tetrahydrofuran into a reaction kettle, and seal the reactor. Introduce 0.5 MPa of hydrogen and carbon monoxide mixed gas H2 / CO (v:v = 1:1) into the reaction kettle, and fully displace the reactor. Weigh 20 g of reactant propylene, and then charge 4.0 MPa of hydrogen and carbon monoxide mixed gas H2 / CO (v:v = 1:1). Set the stirring rate to 500 rpm, the reaction temperature to 100°C, and the reaction time to 4 h. After the reaction, analyze and quantify the reaction products by GC-MS. The analysis results are shown in Table 1.

[0103] The loss rate of cobalt, the reaction selectivity, the conversion rate, and the n / i ratio of the products in the above application examples and the comparative examples were tested, and the test results are shown in Table 1.

[0104] Table 1, performance test results

[0105]

[0106] In Table 1, l / b refers to the ratio of normal alcohol and isomeric alcohol in the products.

[0107] From the above results in Table 1, it can be seen that, compared with the cobalt-based catalysts of the comparative examples, the bimetallic molecular sieve catalyst Co-M@MFI prepared by the method of the present application has higher catalytic activity and alcohol selectivity in the olefin hydroformylation / hydrogenation reaction, and significantly avoids the loss of active cobalt during the reaction.

[0108] The above detailed description does not constitute a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can occur depending on design requirements and other factors.

[0109] Any modifications, equivalent replacements, and improvements within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing a bimetallic molecular sieve catalyst, the method comprising: (1) dissolving a cobalt-containing compound and an M-containing compound in water to obtain a metal salt solution containing cobalt and M metal components, M = one or more of Zn, Mg, Mo or Ce; (2) weighing a certain amount of complex amine and adding it to the aqueous solution of step (1), stirring the mixture at room temperature to obtain a bimetallic complex amine solution; (3) weighing a certain amount of organic template agent into water, stirring the mixture at room temperature, then adding the metal complex amine solution obtained in step (2), and stirring to obtain a mixed solution; (4) adding a suitable amount of silicon source and aluminum source to the mixed solution of step (3) and stirring at room temperature to form a mixed gel; (5) after high-temperature crystallization and growth of the mixed gel of step (4), a crude molecular sieve is obtained; (6) the crude molecular sieve obtained in step (5) is washed, dried, calcined, shaped, and then calcined to obtain a bimetallic molecular sieve catalyst Co-M@MFI.

2. The production method according to claim 1, wherein, The cobalt-containing compound in step (1) includes one or more of cobalt nitrate, cobalt chloride, cobalt acetylacetonate, cobalt carbonyl and their hydrates; The M-containing compound includes one or more of hydrated zinc nitrate, hydrated magnesium nitrate, ammonium molybdate, and hydrated cerium nitrate; The mass ratio of M to Co is 0.5-15:

1.

3. The production method according to claim 1, wherein In step (2), the complex amine is one or more combinations of ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, and ethylenediaminetetraacetate; The molar ratio of complex amine to the sum of cobalt-containing compound and M-containing compound is 1-100:

1.

4. The production method according to claim 3, wherein In step (2), the molar ratio of complex amine to the sum of cobalt-containing compound and M-containing compound is 5-20:

1.

5. The production method according to claim 1, wherein In step (3), the organic template agent is one or more of tetraethylammonium hydroxide and / or tetrapropylammonium hydroxide; The molar ratio of organic template agent to the sum of cobalt-containing compound and M-containing compound is 1-100:

1.

6. The production method according to claim 5, wherein In step (3), the molar ratio of organic template agent to the sum of cobalt-containing compound and M-containing compound is 2-10:

1.

7. The production method according to claim 1, wherein The silicon source in step (4) is at least one selected from silica gel, silica sol and organosilicate, and the molar ratio of silicon in the silicon source to the sum of cobalt-containing compound and M-containing compound is 5-1000; The aluminum source is at least one selected from sodium metaaluminate, sodium aluminate, variscite, gibbsite, aluminum isopropoxide, aluminum nitrate, and metallic aluminum solution; The molar ratio between silicon in the silicon source and aluminum in the aluminum source is 20-100.

8. The production method according to claim 1, wherein The molar ratio of silicon in the silicon source to the sum of cobalt-containing compound and M-containing compound in step (4) is 5-10:1; The molar ratio between silicon in the silicon source and aluminum in the aluminum source is 40-60.

9. The production method according to claim 1, wherein, The high-temperature crystallization conditions in step (5) are: temperature 80-200℃, time 1-8 days.

10. The production method according to claim 1, wherein, The calcination conditions in step (6) are: air atmosphere calcination, temperature 300-800℃, time 4-24h; The shaping treatment in step (6) is at least one of rolling shaping, extrusion shaping and tabletting shaping; The re-baking treatment in step (6) is carried out at a temperature of 300-800 DEG C for 4-24 hours.

11. A process for the hydroformylation / hydrogenation of straight-chain olefins, wherein, The method comprises reacting linear olefins with synthesis gas to produce alcohol under the action of the catalyst prepared according to the preparation method of any one of claims 1-10.

12. The method of claim 11, wherein, The linear olefins include one or more of C2-C20 terminal olefins and internal olefin compounds.

13. The method of claim 12, wherein, The linear olefins are selected from C2-C10 terminal olefins and internal olefins.

14. The method of any one of claims 11-13, wherein, The reaction temperature is 60-200 DEG C; The total pressure of carbon monoxide and hydrogen is 0.5-10 MPa, and the hydrogen-carbon ratio is 0.2-5.

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