Catalyst system and application, preparation method of pentenoate compounds

Abstract

The present application relates to alkoxy carbonylation reaction catalyst technical field, disclose a kind of catalyst system and application, the preparation method of pentenoate compound, the catalyst system includes group VIII metal compound, phosphine ligand and ZSM-5 molecular sieve;Wherein, the ZSM-5 molecular sieve 051 crystal face and 101 crystal face diffraction peak relative intensity ratio is 50-90%.The catalyst system of the present application adopts low ZSM-5 type molecular sieve, it is helpful to the performance of butadiene alkoxy carbonylation reaction, while improving the selectivity of straight chain 1,4-addition product, and simple with product separation, after the reaction is ended, the molecular sieve can be recycled, reduce cost;And will not introduce acidic organic matter, the corrosion of device is small, equipment investment cost is low, while the catalyst system of the present application in long period operation, ZSM-5 type molecular sieve will not react with raw material alcohol, avoid the problem that organic acid needs to be added due to esterification consumption, strong implementability.

Description

Technical Field

[0001] This invention relates to the field of alkoxycarbonylation reaction catalyst technology, specifically to a catalyst system and its application, and a method for preparing pentenoate compounds. Background Technology

[0002] Alkoxycarbonylation refers to the reaction of alkenes with CO and alcohols under transition metal catalysis to yield ester compounds, achieving 100% atom utilization. Butadiene undergoes alkoxycarbonylation to generate pentenoate platform carbonyl compounds, which can be further converted into adipate esters, caprolactam, adipic acid, hexanediol, or hexanediamine in an environmentally friendly and atom-economical manner. This novel nylon 66 intermediate route is of great significance to the chemical industry.

[0003] Chinese invention patents CN1141286A, CN1040102C, and CN1221516C disclose methods for preparing pentenoate esters by carbonylation reaction of butadiene or butadiene derivatives with CO and alcohols in a catalyst system composed of group VIII metals / phosphine ligands / organic acids. All of these patents require the addition of acidic organic compounds as auxiliaries. The introduction of these acidic organic compounds leads to difficulties in product separation, high energy consumption, severe equipment corrosion, and high investment costs. CN112939776A discloses a method for preparing pentenoate esters from butadiene using a functionalized ionic liquid as a solvent in a palladium / phosphine complex catalytic system. Although no additional acidic auxiliaries are added, the ionic liquid preparation method is complex and costly, making it economically unfavorable. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems in existing technologies for alkoxycarbonylation reactions, such as the introduction of acidic organic compounds as promoters into the catalyst system, leading to difficulties in product separation and equipment corrosion; furthermore, during long-term operation of the equipment, organic acids may undergo esterification reactions with the raw material alcohol, requiring periodic replenishment of organic acids and removal of esterification byproducts. This invention provides a catalyst system and its application, as well as a method for preparing pentenoate compounds. This catalyst system does not require the use of acidic organic compounds; instead, it utilizes inexpensive ZSM-5 molecular sieves, effectively solving the problems of difficult product separation, high cost, and equipment corrosion.

[0005] To achieve the above objectives, the first aspect of the present invention provides a catalyst system comprising a group VIII metal compound, a phosphine ligand, and a ZSM-5 molecular sieve.

[0006] The relative intensity ratio of the diffraction peaks of the 051 crystal plane and the 101 crystal plane of the ZSM-5 molecular sieve is 50-90%.

[0007] A second aspect of the present invention provides the use of the catalyst system described in the first aspect in the preparation of pentenoate compounds.

[0008] A third aspect of the present invention provides a method for preparing pentenoate compounds, the method comprising: reacting butadiene, alcohol and carbon monoxide in the presence of the catalyst system described in the first aspect.

[0009] Through the above technical solution, the present invention can achieve at least the following beneficial effects:

[0010] (1) The catalyst system of the present invention uses inexpensive ZSM-5 molecular sieve, which helps the butadiene alkoxycarbonylation reaction to proceed, while improving the selectivity of the straight-chain 1,4-addition product. It is also easy to separate from the product. After the reaction, the molecular sieve can be recycled, reducing costs.

[0011] (2) The catalyst system used in the preparation of pentenoate compounds in this invention does not introduce acidic organic matter, has low corrosiveness to the equipment, and has low equipment investment cost.

[0012] (3) During long-term operation, the ZSM-5 molecular sieve of the catalyst system of the present invention will not react with the raw material alcohol, thus avoiding the problem of organic acid needing to be replenished due to esterification consumption, and is highly feasible. Detailed Implementation

[0013] 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.

[0014] The first aspect of this invention provides a catalyst system comprising a group VIII metal compound, a phosphine ligand, and a ZSM-5 molecular sieve;

[0015] The relative intensity ratio of the diffraction peaks of the 051 crystal plane and the 101 crystal plane of the ZSM-5 molecular sieve is 50-90%.

[0016] During their research, the inventors of this invention discovered that by introducing inexpensive solid ZSM-5 molecular sieve as an acidic additive and controlling the relative intensity ratio of the diffraction peaks of each crystal plane of the ZSM-5 molecular sieve, the catalytic performance of the catalyst system can be effectively improved, which is conducive to realizing continuous industrial production and solving problems such as high energy consumption, resource waste and environmental pollution.

[0017] In this invention, preferably, the relative intensity ratio of the diffraction peaks of the 051 crystal plane and the 101 crystal plane of the ZSM-5 molecular sieve is 68-82% (for example, it can be any two values ​​formed by 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, or any value within that range).

[0018] In this invention, by controlling the relative intensity ratio of the diffraction peaks of the 051 and 101 crystal planes of ZSM-5 molecular sieve, the catalytic performance of the catalyst system is improved. Under this catalytic system, the preparation of pentenoate compounds has higher yield and selectivity for linear 1,4-addition products.

[0019] In this invention, preferably, the group VIII metal compound can be a group VIII metal compound commonly used in the art. For example, the group VIII metal compound can be selected from at least one of palladium compounds, cobalt compounds, and rhodium compounds, and more preferably from at least one of palladium chloride (PdCl2), palladium bromide, palladium iodide, palladium acetate (Pd(OAc)2), palladium trifluoroacetate (Pd(TFA)2), palladium acetylacetone, tetra(triphenylphosphine)palladium, (1,5-cyclooctadiene)palladium dichloride, tris(dibenzylideneacetone)palladium, octacarbonyldicobalt, and rhodium trichloride.

[0020] In this invention, preferably, the phosphine ligand can be selected from monodentate phosphine ligands and / or bidentate phosphine ligands, more preferably triphenylphosphine, tri-n-butylphosphine, diphenyl-2-pyridinium phosphine, tris(4-methoxyphenyl)phosphine, tris(3-methoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tricyclohexylphosphine, 1,2-bis(di-tert-butylphosphinemethyl)benzene, 1,4-bis(diphenylphosphine)butane, 4,5-bis(diphenylphosphine)-9,9-dimethyloxanthracene, 4,5-bis(dicyclohexylphosphine)-9,9-dimethyl- At least one of 9H-oxanthracene, 4,6-bis(diphenylphosphine)-10H-phenoxazine, (9,9-dimethyl-9H-xanthon-4,5-diyl)bis(di-tert-butylphosphine), bis(2-diphenylphosphine) ether, 1,1'-bis(diisopropylphosphine)ferrocene, 1,1'-bis(di-tert-butylphosphine)ferrocene, 1,1'-bis(diphenylphosphine)ferrocene, 2,2'-bis(diphenylphosphine)-1,1'-binaphthyl and 2,2'-bis[(diphenylphosphine)methyl]-1,1'-biphenyl.

[0021] In this invention, preferably, the average pore size of the ZSM-5 molecular sieve can be 0.3-2 nm (for example, it can be any two values ​​formed by 0.3 nm, 0.31 nm, 0.4 nm, 0.5 nm, 0.56 nm, 0.6 nm, 0.7 nm, 0.8 nm, 0.9 nm, 1 nm, 1.2 nm, 1.4 nm, 1.6 nm, 1.8 nm, 2 nm, or a value within that range), more preferably 0.31-0.56 nm.

[0022] In this invention, preferably, the specific surface area of ​​the ZSM-5 molecular sieve can be 300-500 m². 2 / g (for example, 300m) 2 / g、310m 2 / g、320m 2 / g、328m 2 / g、330m 2 / g、340m 2 / g, 350m 2 / g、360m 2 / g、370m 2 / g、380m 2 / g、390m 2 / g、400m 2 / g、420m 2 / g、440m 2 / g、460m 2 / g、480m 2 / g、484m 2 / g、490m 2 / g、500m 2 The range formed by any two values ​​in / g and the values ​​within that range, more preferably 328-484m 2 / g.

[0023] In this invention, by controlling the average pore size and specific surface area of ​​ZSM-5 molecular sieve, the catalytic activity of the catalytic system can also be improved, effectively enhancing the catalytic reaction performance.

[0024] In this invention, preferably, the molar ratio of the Group VIII metal compound (calculated as Group VIII metal element) to the phosphine ligand (calculated as phosphorus element) is 1:1-100 (for example, it can be any two ratios from 1:1, 1:5, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100, or any ratio within that range), more preferably 1:1-10.

[0025] In this invention, preferably, in the catalyst system, the molar ratio of the Group VIII metal element in the Group VIII metal compound to the mass of the ZSM-5 molecular sieve is 1:10-100000 (for example, it can be any two ratios from 1:10, 1:100, 1:500, 1:1000, 1:5000, 1:10000, 1:20000, 1:30000, 1:40000, 1:50000, 1:60000, 1:70000, 1:80000, 1:90000, 1:100000, forming a range and a ratio within that range), preferably 1:100-10000.

[0026] In this invention, the components are compounded in the above proportions to obtain a homogeneous catalyst system. The components complement each other to have better catalytic activity, which makes the catalytic reaction proceed better and the resulting product has higher yield and selectivity.

[0027] A second aspect of the present invention provides the use of the catalyst system described in the first aspect in the preparation of pentenoate compounds.

[0028] A third aspect of the present invention provides a method for preparing pentenoate compounds, the method comprising: reacting butadiene, alcohol and carbon monoxide in the presence of the catalyst system described in the first aspect.

[0029] During their research, the inventors of this invention discovered that ZSM-5 molecular sieves, based on their unique structure and function, can effectively promote alkoxycarbonylation reactions and improve the selectivity of straight-chain 1,4-addition products. At the same time, ZSM-5 molecular sieves do not react with the raw material alcohol, thus avoiding the problem of organic acids needing to be replenished due to esterification consumption.

[0030] In this invention, preferably, the alcohol can be selected from alcohols commonly used in the art, for example, alcohols selected from C1-C5, more preferably at least one of methanol, ethanol, propanol, isopropanol, butanol and isobutanol.

[0031] In this invention, preferably, the molar ratio of the catalyst system, calculated as a group VIII metal element, to butadiene can be 1:50-1000 (for example, it can be any two ratios from 1:50, 1:100, 1:150, 1:200, 1:250, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:650, 1:700, 1:750, 1:800, 1:850, 1:900, 1:950, 1:1000, and the ratio within that range), more preferably 1:100-500.

[0032] In this invention, preferably, the molar ratio of butadiene to alcohol can be 1:0.1-100 (for example, it can be any two ratios from 1:0.1, 1:1, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100, or any ratio within that range), more preferably 1:1-10.

[0033] In this invention, preferably, the reaction conditions may include: a reaction temperature of 50-180℃ (e.g., a range formed by any two values ​​from 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, and 180℃, and values ​​within that range), more preferably 100-150℃; and a reaction pressure of 1-10MPa (e.g., 1MPa, 2MPa, or 3MPa). The pressure can be within the range of any two values ​​formed by 1, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, and 10 MPa, and more preferably 3-7 MPa; the reaction time can be 1-24 h (for example, it can be within the range of any two values ​​formed by 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h, and 24 h, and more preferably 2-8 h).

[0034] In this invention, preferably, the carbon monoxide is introduced into the reaction system to maintain a reaction pressure of 1-10 MPa during the reaction process; preferably, the introduction of carbon monoxide maintains a reaction pressure of 3-7 MPa in the reaction system.

[0035] The present invention will be described in detail below through examples. In the following examples, the molecular sieve characterization methods are as follows: X-ray diffraction was used to test the crystal structure of the molecular sieve at a scanning rate of 2° / min, with a measurement range of 5-60°. The specific surface area and pore structure of the molecular sieve were measured by nitrogen physical adsorption-desorption experiments, and the sample was degassed under vacuum at 200℃ for 8 h. The BET specific surface area was calculated using the multi-point BET method, the micropore volume was obtained using the SF method, and the total pore volume of the sample was calculated using a relative pressure (p / p0) of 0.99. The pore size distribution was analyzed using the NLDFT method.

[0036] The reaction conversion and selectivity were analyzed using an Agilent 6890 gas chromatograph.

[0037] Preparation Example

[0038] This preparation example illustrates a general synthetic method for ZSM-5 molecular sieves:

[0039] Using tetraethyl orthosilicate (TEOS, SiO2 content 28.4 wt%) and sodium aluminate (NaAlO2, Al2O3 content 41 wt%) as raw materials, a certain amount of deionized water was added to prepare a sol at a specific SiO2 / Al2O3 molar ratio. Then, a certain amount of tetrapropylammonium hydroxide (TPAOH, 25 wt% aqueous solution) and sodium fluoride (NaF) were added, and the mixture was stirred at 40℃ and 300 rpm for 12 hours to form a homogeneous gel. The gel was transferred to a high-pressure reactor with a polytetrafluoroethylene liner and crystallized at a certain temperature for a certain time. After cooling, it was centrifuged and washed with deionized water until neutral. The resulting solid was dried at 100℃ and calcined at 540℃ to obtain ZSM-5 molecular sieve.

[0040] Example 1

[0041] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein the molar ratio of raw materials SiO2, Al2O3, TPAOH, NaF and H2O was 250:1:12:1.8:40; the crystallization conditions were as follows: first crystallize at 160℃ for 36 hours, and then raise the temperature to 175℃ for 4 hours for further crystallization.

[0042] In a 100 ml steel autoclave (from Parr), Pd(OAc)₂ (0.056 g, 0.25 mmol), 1,4-bis(diphenylphosphine)butane (0.426 g, 1 mmol), methanol (1.44 g, 0.045 mol), and toluene (15 ml) were added sequentially. Then, 0.25 g of molecular sieve ZSM-5 was added, with a relative intensity ratio of 75% between the diffraction peaks of the 051 and 101 crystal planes, an average pore size of 0.43 nm, and a specific surface area of ​​405 m². 2 Add 0.5 g of internal standard trimethylbenzene to a sealed reactor. Remove oxygen three times by purging with nitrogen, then three times by purging with CO. Add butadiene (1.62 g, 0.03 mol), then add CO until the reactor pressure reaches 4 MPa. Maintain the temperature slowly at 150°C using a temperature controller, employing either a slow-cooking method or continuous carbon monoxide purging to ensure constant pressure within the system. The reaction time is 2.5 hours.

[0043] After reacting for 2.5 hours, the reactor was cooled to room temperature and the pressure was released. The resulting liquid was quantitatively analyzed using an Agilent 6890 analyzer. The butadiene conversion and the yield of methyl pentenoate are shown in Table 1.

[0044] Example 2

[0045] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein the molar ratio of raw materials SiO2, Al2O3, TPAOH, NaF and H2O was 100:1:24:1.3:35; the crystallization conditions were as follows: crystallization at 155℃ for 36 hours, followed by further crystallization at 180℃ for 18 hours.

[0046] In a 100 ml steel autoclave (from Parr), Pd(TFA)₂ (0.049 g, 0.15 mmol), 1,2-bis(di-tert-butylphosphine-methyl)benzene (0.118 g, 0.3 mmol), methanol (1.152 g, 0.036 mol), and diphenyl ether (30 ml) were added sequentially. Then, 0.15 g of molecular sieve ZSM-5 was added, which has a relative intensity ratio of 68% between the 051 and 101 crystal plane diffraction peaks, an average pore size of 0.56 nm, and a specific surface area of ​​328 m². 2 Add 0.5 g of internal standard trimethylbenzene to a sealed reactor. Remove oxygen by purging with nitrogen three times, then with CO three times. Add butadiene (1.62 g, 0.03 mol), then add CO until the reactor pressure reaches 4 MPa. Maintain the temperature slowly at 130°C using a temperature controller, employing either a slow-cooking reaction or continuous carbon monoxide flow to ensure constant pressure within the system. The reaction time is 6 hours.

[0047] After reacting for 6 hours, the reactor was cooled to room temperature and the pressure was released. The resulting liquid was quantitatively analyzed using an Agilent 6890 analyzer. The butadiene conversion and the yield of methyl pentenoate are shown in Table 1.

[0048] Example 3

[0049] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein the molar ratio of raw materials SiO2, Al2O3, TPAOH, NaF and H2O was 625:1:6.25:18.7:40; the crystallization conditions were as follows: first crystallize at 140℃ for 72 hours, and then raise the temperature to 180℃ for 6 hours for further crystallization.

[0050] Methyl pentenoate was prepared according to the method in Example 1, except that the relative intensity ratio of the diffraction peaks of the 051 and 101 crystal planes of the molecular sieve ZSM-5 was 82%, and the specific surface area of ​​the molecular sieve ZSM-5 was 484 m². 2 / g, with an average pore size of 0.31nm. The butadiene conversion rate and the yield of the product methyl pentenoate are shown in Table 1.

[0051] Example 4

[0052] ZSM-5 molecular sieve was prepared according to the general synthesis method in the preparation example, wherein the molar ratio of raw materials SiO2, Al2O3, TPAOH, NaF and H2O was 250:1:70:3.75:35; the crystallization conditions were as follows: crystallization at 80℃ for 6 hours, followed by further crystallization at 120℃ for 36 hours.

[0053] Methyl pentenoate was prepared according to the method in Example 1, except that the average pore size of the molecular sieve ZSM-5 was 0.3 nm. The butadiene conversion and the yield of the product methyl pentenoate are shown in Table 1.

[0054] Example 5

[0055] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein sodium fluoride was replaced with F127 template agent, and the molar ratio of raw materials SiO2, Al2O3, TPAOH, F127 template agent and H2O was 333:1:17.3:1.8:40; the crystallization conditions were 130℃ for 36 hours, followed by raising the temperature to 180℃ for 12 hours for further crystallization.

[0056] Methyl pentenoate was prepared according to the method in Example 1, except that the average pore size of the molecular sieve ZSM-5 was 1 nm. The butadiene conversion and the yield of the product methyl pentenoate are shown in Table 1.

[0057] Example 6

[0058] ZSM-5 molecular sieves were prepared according to the general synthesis method of the preparation example, wherein sodium fluoride was replaced with polyacrylic acid (PAA), and the molar ratio of raw materials SiO2, Al2O3, TPAOH, PAA and H2O was 125:1:22.5:0.375:50; the crystallization conditions were as follows: crystallization at 150℃ for 28 hours, followed by raising the temperature to 180℃ for 6 hours of further crystallization.

[0059] Methyl pentenoate was prepared according to the method in Example 1, except that the molecular sieve ZSM-5 had a specific surface area of ​​289 m². 2 / g. The butadiene conversion rate and the yield of the product methyl pentenoate are shown in Table 1.

[0060] Example 7

[0061] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein tetrapropylammonium hydroxide (TPAOH) was replaced with hexadecyltrimethylammonium bromide (CTAB), and the molar ratio of raw materials SiO2, Al2O3, CTAB, NaF and H2O was 500:1:16:2:50; the crystallization conditions were as follows: crystallization at 120℃ for 12 hours, followed by raising the temperature to 180℃ for 6 hours of further crystallization.

[0062] Methyl pentenoate was prepared according to the method in Example 1, except that the molecular sieve ZSM-5 had a specific surface area of ​​505 m². 2 / g. The butadiene conversion rate and the yield of the product methyl pentenoate are shown in Table 1.

[0063] Example 8

[0064] In a 100 ml steel autoclave (from Parr), PdCl2 (0.027 g, 0.15 mmol), 4,6-bis(diphenylphosphino)-10H-phenoxazine (0.165 g, 0.3 mmol), methanol (1.152 g, 0.036 mol), and acetonitrile (30 ml) were added sequentially. Then, 0.15 g of ZSM-5 molecular sieve (prepared in Example 1) was added, wherein the relative intensity ratio of the diffraction peaks of the 051 and 101 crystal planes was 75%, the pore size was 0.43 nm, and the specific surface area was 405 m². 2 Add 0.5 g of internal standard trimethylbenzene to a sealed reactor. Remove oxygen by purging with nitrogen three times, then with CO three times. Add butadiene (1.62 g, 0.03 mol), then add CO until the reactor pressure reaches 4 MPa. Maintain the temperature slowly at 120°C using a temperature controller, employing either a slow-cooking method or continuous carbon monoxide injection to ensure constant pressure within the system. The reaction time is 4 hours.

[0065] After reacting for 4 hours, the reactor was cooled to room temperature and the pressure was released. The resulting liquid was quantitatively analyzed using an Agilent 6890 analyzer. The butadiene conversion rate and the yield of methyl pentenoate are shown in Table 1.

[0066] Example 9

[0067] In a 300 ml steel autoclave (from Parr), PdCl2 (0.037 g, 0.21 mmol), 1,1'-bis(diisopropylphosphino)ferrocene (0.199 g, 0.42 mmol), butanol (7.48 g, 0.101 mol), and toluene (60 ml) were added sequentially. Then, 0.21 g of ZSM-5 molecular sieve (prepared in Example 1) was added, wherein the relative intensity ratio of the diffraction peaks of the 051 crystal plane to the 101 crystal plane was 75%, the pore size was 0.43 nm, and the specific surface area was 405 m². 2 Add 1 g of internal standard trimethylbenzene to a sealed reactor. Remove oxygen three times by purging with nitrogen, then three times by purging with CO. Add butadiene (4.54 g, 0.084 mol), and then add CO until the reactor pressure reaches 4 MPa. Maintain the temperature slowly at 120°C using a temperature controller, employing either a slow-cooking reaction or continuous carbon monoxide flow to ensure constant pressure within the system. The reaction time is 3 hours.

[0068] After reacting for 3 hours, the reactor was cooled to room temperature and the pressure was released. The resulting liquid was quantitatively analyzed using an Agilent 6890 analyzer. The butadiene conversion and the yield of butyl pentenoate are shown in Table 1.

[0069] Example 10

[0070] In a 100 ml steel autoclave (from Parr), PdCl2 (0.027 g, 0.15 mmol), 4,5-bis(diphenylphosphine)-9,9-dimethyloxanthracene (0.174 g, 0.30 mmol), ethanol (1.38 g, 0.03 mol), and toluene (15 ml) were added sequentially. Then, 0.15 g of ZSM-5 molecular sieve (using the ZSM-5 molecular sieve prepared in Example 1) was added, wherein the relative intensity ratio of the diffraction peaks of the 051 crystal plane to the 101 crystal plane was 75%, the pore size was 0.43 nm, and the specific surface area was 405 m². 2 Add 0.5 g of internal standard trimethylbenzene to a sealed reactor. Remove oxygen by purging with nitrogen three times, then with CO three times. Add butadiene (1.62 g, 0.03 mol), then add CO until the reactor pressure reaches 4 MPa. Maintain the temperature slowly at 120°C using a temperature controller, employing either a slow-cooking method or continuous carbon monoxide flow to ensure constant pressure within the system. The reaction time is 2 hours.

[0071] After reacting for 2 hours, the reactor was cooled to room temperature and the pressure was released. The resulting liquid was quantitatively analyzed using an Agilent 6890 analyzer. The butadiene conversion and the yield of ethyl pentenoate are shown in Table 1.

[0072] Comparative Example 1

[0073] Methyl pentenoate was prepared according to the method in Example 1, except that ZSM-5 molecular sieve was not added. The butadiene conversion and the yield of the product methyl pentenoate are shown in Table 1.

[0074] Comparative Example 2

[0075] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein the molar ratio of raw materials SiO2, Al2O3, TPAOH, NaF and H2O was 333:1:16.6:2.6:45; the crystallization conditions were as follows: first crystallize at 80℃ for 12 hours, and then raise the temperature to 155℃ for 24 hours for further crystallization.

[0076] Methyl pentenoate was prepared according to the method in Example 1, except that the relative intensity ratio of the diffraction peaks of the 051 and 101 crystal planes of the ZSM-5 molecular sieve was 48%. The butadiene conversion rate and the yield of the product methyl pentenoate are shown in Table 1.

[0077] Comparative Example 3

[0078] ZSM-5 molecular sieve was prepared according to the general synthesis method of the preparation example, wherein sodium fluoride was replaced with ammonium fluoride (NH4F), and the molar ratio of raw materials SiO2, Al2O3, TPAOH, NH4F and H2O was 250:1:23.3:13.3:50; the crystallization conditions were as follows: crystallization at 80℃ for 6 hours, followed by raising the temperature to 150℃ for 24 hours for further crystallization.

[0079] Methyl pentenoate was prepared according to the method in Example 1, except that the relative intensity ratio of the diffraction peaks of the 051 and 101 crystal planes of the ZSM-5 molecular sieve was 97%. The butadiene conversion rate and the yield of the product methyl pentenoate are shown in Table 1.

[0080] Comparative Example 4

[0081] Methyl pentenoate was prepared according to the method in Example 1, except that the organic acid 2,4,6-trimethylbenzoic acid was used instead of ZSM-5 molecular sieve. The butadiene conversion and the yield of the product methyl pentenoate are shown in Table 1.

[0082] Table 1

[0083]

[0084]

[0085] 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. A catalyst system, characterized in that, The catalyst system includes group VIII metal compounds, phosphine ligands, and ZSM-5 molecular sieves; The relative intensity ratio of the diffraction peaks of the 051 crystal plane and the 101 crystal plane of the ZSM-5 molecular sieve is 50-90%.

2. The catalyst system according to claim 1, wherein, The relative intensity ratio of the diffraction peaks of the 051 and 101 crystal planes of the ZSM-5 molecular sieve is 68-82%.

3. The catalyst system according to claim 1 or 2, wherein, The group VIII metal compound is selected from at least one of palladium compounds, cobalt compounds, and rhodium compounds, and is preferably at least one of palladium chloride, palladium bromide, palladium iodide, palladium acetate, palladium trifluoroacetate, palladium acetylacetonate, tetra(triphenylphosphine)palladium, (1,5-cyclooctadiene)palladium dichloride, tris(dibenzylacetone)palladium, octacarbonyldicobalt, and rhodium trichloride.

4. The catalyst system according to claim 1 or 2, wherein, The phosphine ligand is selected from monodentate phosphine ligands and / or bidentate phosphine ligands, preferably triphenylphosphine, tri-n-butylphosphine, diphenyl-2-pyridinium phosphine, tris(4-methoxyphenyl)phosphine, tris(3-methoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tricyclohexylphosphine, 1,2-bis(di-tert-butylphosphinemethyl)benzene, 1,4-bis(diphenylphosphine)butane, 4,5-bis(diphenylphosphine)-9,9-dimethyloxanthracene, 4,5-bis(dicyclohexylphosphine)-9,9-dimethyl-9H-oxanthracene. At least one of 4,6-bis(diphenylphosphino)-10H-phenoxazine, (9,9-dimethyl-9H-xanthon-4,5-diyl)bis(di-tert-butylphosphine), bis(2-diphenylphosphine) ether, 1,1'-bis(diisopropylphosphino)ferrocene, 1,1'-bis(di-tert-butylphosphino)ferrocene, 1,1'-bis(diphenylphosphino)ferrocene, and 2,2'-bis(diphenylphosphine)-1,1'-binaphthyl, 2,2'-bis[(diphenylphosphino)methyl]-1,1'-biphenyl.

5. The catalyst system according to claim 1 or 2, wherein, The average pore size of the ZSM-5 molecular sieve is 0.3-2 nm, preferably 0.31-0.56 nm; And / or, the specific surface area of ​​the ZSM-5 molecular sieve is 300-500 m². 2 / g, preferably 328-484m 2 / g.

6. The catalyst system according to claim 1 or 2, wherein, The molar ratio of the Group VIII metal compound (calculated as Group VIII metal element) to the phosphine ligand (calculated as phosphorus element) is 1:1-100, preferably 1:1-10; And / or, in the catalyst system, the molar ratio of the group VIII metal element in the group VIII metal compound to the mass of the ZSM-5 molecular sieve is 1:10-100000, preferably 1:100-10000.

7. The use of the catalyst system according to any one of claims 1-6 in the preparation of pentenoate compounds.

8. A method for preparing a pentenoic acid ester compound, characterized in that, The preparation method comprises: reacting butadiene, alcohol and carbon monoxide in the presence of the catalyst system described in any one of claims 1-6.

9. The preparation method according to claim 8, wherein, The alcohol is selected from C1-C5 alcohols, preferably at least one of methanol, ethanol, propanol, isopropanol, butanol and isobutanol; And / or, the molar ratio of the catalyst system to butadiene, calculated as group VIII metal elements, is 1:50-1000, preferably 1:100-500; And / or, the molar ratio of butadiene to alcohol is 1:0.1-100, preferably 1:1-10.

10. The preparation method according to claim 8 or 9, wherein, The reaction conditions include: a reaction temperature of 50-180℃, preferably 100-150℃; a reaction pressure of 1-10MPa, preferably 3-7MPa; and a reaction time of 1-24h, preferably 2-8h.

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