CN114534794A

CN114534794A - Solid heterogeneous catalyst and preparation and application thereof

Info

Publication number: CN114534794A
Application number: CN202011326911.5A
Authority: CN
Inventors: 丁云杰; 孙钊; 严丽; 李存耀; 程显波
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2020-11-24
Filing date: 2020-11-24
Publication date: 2022-05-27

Abstract

The invention relates to a solid heterogeneous catalyst and a preparation method and application thereof, wherein the solid heterogeneous catalyst consists of a metal component and an organic ligand polymer, wherein the metal component is one or more of metal Pd, Ru, Ni, Ir, Rh, Mo, Fe or Cu, the organic ligand polymer is a polymer with a large specific surface area and a hierarchical pore structure, which is generated by carrying out solvent thermal copolymerization on a phosphine ligand monomer containing a vinyl functional group and an acidic organic monomer containing a vinyl, and the metal component and a P atom in the organic ligand polymer skeleton form a coordination bond and are highly dispersed and stably present on an organic ligand polymer carrier. The catalyst of the invention is easy to separate from reactants and products, and has wide industrial application prospect.

Description

Solid heterogeneous catalyst and preparation and application thereof

Technical Field

The invention relates to a solid heterogeneous catalyst for an alkoxy carbonylation reaction, a preparation method and application thereof, belonging to the technical field of heterogeneous catalysis.

Background

Homogeneous catalysis systems are classical reaction systems, have high catalytic activity and high selectivity of target products under mild reaction conditions, but have the problem that the catalyst and reaction materials are difficult to separate. Heterogeneous catalysis has an obvious advantage over homogeneous catalysis, i.e., the catalyst is easily separated from the reaction materials, and has the main problems of harsh reaction conditions, relatively low reaction activity, etc. Therefore, it is a hot spot of scientific research to develop a series of novel immobilized heterogeneous catalysts with the advantages of homogeneous catalysis and heterogeneous catalysis. In recent years, the design and synthesis of porous organic polymer materials are becoming one of the new hotspots in the field of porous material research. Compared with traditional inorganic microporous materials and metal organic framework Materials (MOFs), the organic microporous polymer has a skeleton composed of pure organic molecules, is connected with each other through covalent bonds, and has open pore channels and excellent pore properties. More importantly, due to the diversity of organic chemical synthesis methods, abundant synthesis paths and construction modes are provided for the construction of an organic molecule network, the material can have corresponding properties by purposefully introducing functionalized organic molecules, and the pore properties of the material can be regulated and controlled by adjusting the structure of the organic molecules. Besides, the metal functionalized porous organic polymer material can introduce metal active units with catalytic activity into the porous organic polymer at fixed points, so that the metal active units are highly dispersed in the organic copolymer carrier in a monoatomic form, and therefore, the metal active sites are stabilized, and the utilization efficiency of metal is improved to a certain extent.

The reaction of alcohols, olefins and CO catalyzed by catalysts to produce esters is called alkoxycarbonylation, the resulting esters have a very wide application in the industrial field, and can be used as intermediates in organic synthesis and in the manufacture of perfumes, and the esters are also excellent solvents which can be used as solvents in the manufacture of cellulose ethers and esters, and also as solvents for a variety of natural and synthetic resins. However, the existing alkoxycarbonylation reaction systems are homogeneous systems, and the catalyst and the reaction liquid are difficult to separate.

In summary, a green, highly efficient and recyclable heterogeneous catalyst for alkoxycarbonylation suitable for practical industrial applications is the main research direction in this field.

Disclosure of Invention

In order to solve the problems, the invention aims to provide a solid heterogeneous catalyst with metal active components loaded by organic ligand polymers, and a preparation method and application thereof.

Therefore, the invention provides a solid heterogeneous catalyst applied to an alkoxy carbonylation reaction, which is characterized in that: the organic ligand polymer is a polymer with large specific surface area and a hierarchical pore structure, which is generated by carrying out solvent thermal copolymerization on a phosphine ligand monomer containing vinyl functional groups and an acidic organic monomer containing vinyl, wherein the metal component is one or more of metals Pd, Ru, Ni, Ir, Rh, Mo, Fe or Cu, and the metal component and a P atom in the organic ligand polymer skeleton form a coordinate bond and are highly dispersed and stably present on an organic ligand polymer carrier.

In a preferred embodiment, the metal component represents from 0.01 to 17.0%, preferably from 0.2 to 5%, of the total weight of the solid heterogeneous catalyst.

In a preferred embodiment, the phosphine ligand containing vinyl functional groups is one or more selected from the group consisting of:

in a preferred embodiment, the vinyl-containing acidic organic monomer is one or more selected from the group consisting of:

in a preferred embodiment, the specific surface area of the organic ligand polymer is 100-3000m²Per g, pore volume of 0.1-5.0cm³(ii)/g, the pore size distribution is 0.1-100.0 nm.

In a preferred embodiment, the preparation method of the solid heterogeneous catalyst comprises the following preparation steps: a) adding a free radical initiator into a solvent containing a vinyl functionalized phosphine ligand monomer under the protection of 273-473K and inert gas, then adding an acidic organic monomer containing vinyl, and stirring for 0.5-100 hours; b) standing the solution obtained in the step a) in a hydrothermal autoclave for 0.5-100 hours under the protection of 323-473K and inert gas to perform solvent thermal polymerization; c) after the step b) is finished, the solvent is removed in vacuum at the temperature of 273-473K, and the organic ligand polymer is obtained; d) and (3) placing the organic ligand polymer in a solvent containing an active metal component, stirring for 0.5-100 hours under the protection atmosphere of 273-473K and inert gas, and then removing the solvent in vacuum under the temperature condition of 273-473K to obtain the solid heterogeneous catalyst of which the active metal component is supported by the organic ligand polymer.

In a preferred embodiment, the solvent used in steps a) and d) of the catalyst preparation method is one or more of benzene, toluene, tetrahydrofuran, methanol, ethanol, dichloromethane, dichloroethane or deionized water; the free radical initiator used in step a) is one or more of cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl hydroperoxide, azobisisobutyronitrile or azobisisoheptonitrile.

In a preferred embodiment, the weight ratio of the free radical initiator to the organic monomer in the catalyst preparation process is from 1:500 to 1: 5.

In a preferred embodiment, the use of the solid heterogeneous catalyst in the alkoxycarbonylation reaction refers to the alkoxycarbonylation reaction of the alcohol raw material and the mixed gas of olefin and CO in a fixed bed, a trickle bed, a slurry bed or a tank reactor in the presence of the solid heterogeneous catalyst, wherein the reaction temperature is 273-^-1The space velocity of the olefin and the CO gas is 100-^-1The molar ratio of the olefin feedstock to the CO feedstock is from 1:1 to 1: 100.

In a preferred embodiment, the inert gas atmosphere during the synthesis of the organic ligand polymer is one or more of argon, helium and nitrogen.

The benefits of the present invention include, but are not limited to, the following:

compared with the existing alkoxy carbonylation catalyst, the solid heterogeneous catalyst of the invention has simple preparation method; the metal component and the P atom in the polymer carrier exist on the carrier stably due to coordination; the polymer carrier has large specific surface area and a hierarchical pore structure, and the metal components can be highly dispersed on the carrier, so that the solid heterogeneous catalyst has excellent catalytic reaction performance and higher stability. In addition, the catalyst of the invention is a heterogeneous catalyst macroscopically, so the catalyst has obvious superiority in the aspects of recycling, separating reactants and products and the like, and has wide industrial application prospect.

In the alkoxy carbonylation reaction of the catalyst, on one hand, a metal component and a P atom in a polymer carrier exist on the carrier stably due to coordination; on the other hand, the polymer carrier has large specific surface area and a hierarchical pore structure, and the metal components can be highly dispersed on the carrier, so that the solid heterogeneous catalyst has excellent catalytic reaction performance and stability, is easy to separate from reactants and products, and has wide industrial application prospects.

Drawings

FIG. 1 is a schematic diagram of the solid heterophasic polymer synthesis scheme of the present invention.

FIG. 2 is N of the solid heterogeneous catalyst of the present invention₂Adsorption and desorption isotherms and pore size distribution curves.

Detailed Description

In order to better illustrate the preparation of the catalyst of the invention and its use in alkoxycarbonylation reactions, some examples of the preparation of catalyst samples and their use in reaction processes are given below, but the invention is not limited to the examples listed. As used herein, "percent" is based on weight unless specifically stated otherwise.

Example 1

8.0 g of tris (4-vinylphenyl) phosphine was dissolved in 100ml of tetrahydrofuran solvent under 298K and argon atmosphere, 0.25 g of azobisisobutyronitrile, a radical initiator, 2.0g of p-vinylbenzenesulfonic acid was added to the above solution, and the mixture was stirred for 0.5 hour. And transferring the stirred solution into a hydrothermal autoclave, and carrying out solvothermal polymerization for 24h under the protection of 373K and argon gas. And cooling to room temperature after the polymerization, and vacuumizing the solvent at the temperature of 333K to obtain the corresponding porous organic polymer.

0.0114 of palladium (II) acetate is weighed and dissolved in 50ml of tetrahydrofuran solvent under the protection of 298K and inert gas, 1.0 g of the porous organic polymer prepared above is added, and stirring is carried out for 24 hours. Subsequently, the solvent was evacuated under 333K temperature to obtain a solid heterogeneous catalyst in which the metal component was supported by the organic ligand polymer. The synthetic route of the solid heterogeneous catalyst of the present invention is schematically shown in FIG. 1, and N of the solid heterogeneous catalyst of the present invention₂The absorption and desorption isotherms and the pore size distribution curve are shown in FIG. 2, and the catalyst has good specific surface area and abundant multi-stage pore channel structure. The metal loading was 0.5 wt%.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing mixed gas of ethylene and CO (ethylene: CO is 1:2, volume ratio is the same as below), pumping a methanol raw material solution into the reactor through a high-pressure metering pump to start reaction, wherein the reaction temperature of the ethylene and the methanol for preparing the methyl propionate is 105 ℃, the reaction pressure is 2MPa, and the methanol liquid hourly space velocity is 0.1h^-1CO/methanol molar ratio of 50. And collecting the liquid product methyl propionate in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, with toluene as an internal standard. The reaction off-gas was analyzed on-line using HP-7890N gas chromatography equipped with Porapak-QS column and TCD detector. The specific reaction results are shown in Table 1.

Example 2

In example 2, the catalyst preparation and reaction procedures were the same as in example 1 except that 0.0212 g of rhodium trichloride was weighed instead of 0.0114 g of palladium (II) acetate. The metal loading was 0.7 wt%. The specific reaction results are shown in Table 1.

Example 3

In example 3, the catalyst preparation and reaction procedures were the same as in example 1 except that 0.0175 g of cobalt acetate was weighed instead of 0.0114 g of palladium (II) acetate. The metal loading was 0.5 wt%. The specific reaction results are shown in Table 1.

Example 4

In example 4, the catalyst preparation and reaction procedure were the same as in example 1 except that 0.0366 g of copper (II) acetylacetonate were weighed out in place of 0.0114 g of palladium (II) acetate. The metal loading was 0.9 wt%. The specific reaction results are shown in Table 1.

Example 5

In example 5, the polymer synthesis process was the same as in example 1 except that the tetrahydrofuran solvent was replaced with a methylene chloride solvent.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing a mixed gas of propylene and CO (the volume ratio of the propylene to the CO is 1:2, the same below), pumping a methanol raw material solution into the reactor through a high-pressure metering pump to start reaction, wherein the reaction temperature of the methyl butyrate prepared from the propylene and the methanol is 110 ℃, the reaction pressure is 2.5MPa, and the methanol liquid hourly space velocity is 0.12h^-1CO/methanol molar ratio 40. And collecting the liquid product methyl butyrate in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, with toluene as an internal standard. The reaction off-gas was analyzed on-line using HP-7890N gas chromatography equipped with Porapak-QS column and TCD detector. The specific reaction results are shown in Table 1.

Example 6

In example 6, the polymer synthesis process was the same as in example 1 except that stirring was carried out for 12 hours instead of 0.5 hours.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing a mixed gas of 1-butene and CO (1-butene: CO ═ 1:6), pumping a methanol raw material into the reactor through a high-pressure metering pump to start reaction, wherein the reaction temperature of 1-butene and methanol to prepare methyl valerate is 100 ℃, and the reaction pressure is 25MPa, methanol liquid hourly space velocity of 0.12h^-1CO/methanol molar ratio 40. The liquid product was collected in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, using methanol as an internal standard. The reaction off-gas was analyzed on-line using HP-7890N gas chromatography equipped with Porapak-QS column and TCD detector. The specific reaction results are shown in Table 1.

Example 7

In example 7, the catalyst preparation was the same as in example 1 except that the radical initiator was dibenzoyl peroxide instead of azobisisobutyronitrile.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing a mixed gas of 1-butene and CO (1-butene: CO ═ 1:6), pumping a methanol raw material into the reactor through a high-pressure metering pump to start reaction, wherein the reaction temperature of 1-butene and methanol to prepare methyl valerate is 105 ℃, the reaction pressure is 2.5MPa, and the methanol liquid hourly space velocity is 0.12h^-1CO/methanol molar ratio 40. The liquid product was collected in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, with methanol as internal standard. The reaction off-gas was analyzed on-line using HP-7890N gas chromatography equipped with Porapak-QS column and TCD detector. The specific reaction results are shown in Table 1.

Example 8

In example 8, the catalyst was prepared in the same manner as in example 1 except that 0.1 g of azobisisobutyronitrile as a radical initiator was replaced with 0.25 g of azobisisobutyronitrile.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing CO pure gas, pumping the raw materials of 1-pentene and methanol solution into the reactor through a high-pressure metering pump respectively to start reaction, wherein the reaction temperature of 1-pentene and methanol to methyl hexanoate is 100 ℃, the reaction pressure is 2MPa, and the hourly space velocities of 1-pentene and methanol solution are 0.1h^-1CO/methanol molar ratio 40. The liquid product was collected in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, with toluene as an internal standard. The reaction tail gas was subjected to HP-7890N gas chromatography equipped with Porapak-QS column and TCD detectorAn on-line analysis is performed. The specific reaction results are shown in Table 1.

Example 9

In example 8, the catalyst was prepared in the same manner as in example 1 except that 0.1 g of azobisisobutyronitrile as a radical initiator was replaced with 0.5 g of azobisisobutyronitrile.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing CO pure gas, pumping the raw materials of 1-pentene and methanol solution into the reactor through a high-pressure metering pump respectively to start reaction, wherein the reaction temperature of 1-pentene and methanol for preparing methyl hexanoate is 105 ℃, the reaction pressure is 2MPa, and the hourly space velocities of 1-pentene and methanol solution are 0.12h^-1CO/methanol molar ratio 40. The liquid product was collected in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, with toluene as an internal standard. The reaction off-gas was analyzed on-line using HP-7890N gas chromatography equipped with a Porapak-QS column and a TCD detector. The specific reaction results are shown in Table 1.

Example 10

In example 1, the catalyst preparation process was the same as in example 1 except that 2.0g of p-vinylbenzenesulfonic acid was replaced with 2.0g of vinylsulfonic acid.

Adding the prepared solid heterogeneous catalyst into a trickle bed reactor, introducing CO pure gas, pumping raw materials of 1-hexene and methanol solution into the reactor through a high-pressure metering pump respectively to start reaction, wherein the reaction temperature of 1-hexene and methanol for preparing methyl heptanoate is 100 ℃, the reaction pressure is 2MPa, and the hourly space velocities of 1-hexene and methanol are 0.1h^-1CO/methanol molar ratio 40. The liquid product was collected in a cold trap collection tank. The liquid product was analyzed by HP-7890N gas chromatography using an HP-5 capillary column and FID detector, with toluene as an internal standard. The reaction off-gas was analyzed on-line using HP-7890N gas chromatography equipped with Porapak-QS column and TCD detector. The specific reaction results are shown in Table 1.

The present invention has been described in detail above, but the present invention is not limited to the specific embodiments described herein. It will be understood by those skilled in the art that other modifications and variations may be made without departing from the scope of the invention. The scope of the invention is defined by the appended claims.

TABLE 1 results of the alkoxycarbonylation reaction

Claims

1. A solid heterogeneous catalyst is composed of a metal component and an organic ligand polymer, wherein the metal component is one or more of metal Pd, Ru, Ni, Ir, Rh, Mo, Fe or Cu, the organic ligand polymer is a polymer generated by solvent thermal copolymerization of a phosphine ligand monomer containing vinyl functional groups and an acidic organic monomer containing vinyl, and the metal component and a P atom in the organic ligand polymer skeleton form a coordinate bond and are present on an organic ligand polymer carrier.

2. The solid heterogeneous catalyst according to claim 1, characterized in that: the metal component represents 0.01 to 17.0%, preferably 0.2 to 5%, of the total weight of the solid heterogeneous catalyst.

3. The solid heterogeneous catalyst according to claim 1, characterized in that: the phosphine ligand containing vinyl functional groups is one or more of the following compounds L1-L8:

the acidic organic monomer containing vinyl is one or more selected from the following organic substances S1-S11:

4. according to claim1, the solid heterogeneous catalyst is characterized in that: the specific surface area of the organic ligand polymer is 100-3000m²Per g, pore volume of 0.1-5.0cm³(ii)/g, the pore size distribution is 0.1-100.0 nm.

5. A process for the preparation of a solid heterogeneous catalyst according to any of claims 1 to 4, said process comprising:

a) adding a monodentate organic phosphine ligand, adding an acidic organic monomer containing vinyl, adding or not adding a cross-linking agent, and then adding a free radical initiator into an organic solvent at 223-313K under an inert gas atmosphere, mixing, and stirring the mixture for 0.1-100 hours, wherein the preferable stirring time range is 0.1-1 hour;

the molar ratio of the monodentate organophosphine ligand to the vinyl-containing acidic organic monomer is 0.01: 1-10: 1, the molar ratio of the monodentate organophosphine ligand to the free radical initiator is 300: 1-10: 1, and the concentration range of the monodentate organophosphine ligand in the organic solvent is 0.01-1000g/L before the monodentate organophosphine ligand is polymerized into the organic polymer;

under the condition that the monodentate organophosphine ligand is added into the cross-linking agent in the step a), the molar ratio of the monodentate organophosphine ligand to the cross-linking agent is 0.01: 1-10: 1;

b) transferring the mixed solution prepared in the step a) into a synthesis autoclave, and standing for 1-100 hours by adopting a solvent thermal polymerization method under the atmosphere of 323-473K and inert gas for polymerization reaction to obtain a phosphine-containing porous organic polymer;

c) vacuum-pumping the polymer obtained in the step b) at room temperature to remove the solvent, thus obtaining the organic polymer containing naked P with a hierarchical pore structure, namely the carrier of the heterogeneous catalyst;

d) and (3) placing the organic ligand polymer in a solvent containing an active metal component, stirring for 0.5-100 hours under the protection atmosphere of 273-473K and inert gas, and then removing the solvent in vacuum under the temperature condition of 273-473K to obtain the solid heterogeneous catalyst of which the active metal component is supported by the organic ligand polymer.

6. The method according to claim 5, wherein the solvent used in steps a) and d) is one or more of benzene, toluene, tetrahydrofuran, methanol, ethanol, dichloromethane, dichloroethane or deionized water;

the cross-linking agent is one or more than two of styrene, ethylene, propylene, divinyl benzene, dimethoxymethane, diiodomethane, paraformaldehyde or 1,3, 5-triethylalkynyl benzene;

the free radical initiator used in step a) is one or more of cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl hydroperoxide, azobisisobutyronitrile or azobisisoheptonitrile.

7. Use of a solid heterogeneous catalyst according to any one of claims 1 to 4 for the alkoxycarbonylation of an alcohol feedstock with a mixture of olefins and CO.

8. The method as claimed in claim 7, wherein the alkoxycarbonylation reaction is carried out in a fixed bed, trickle bed, slurry bed or kettle reactor by using the alcohol raw material and the olefin and CO mixed gas in the presence of the solid heterogeneous catalyst, wherein the reaction temperature is 273-573K, the reaction pressure is 0.05-20.0MPa, and the hourly space velocity of the alcohol liquid is 0.01-20.0h^-1The space velocity of the olefin and the CO gas is 100-^-1The molar ratio of the olefin feedstock to the CO feedstock is from 1:1 to 1: 100.

9. The method according to claim 7 or 8, wherein the alcohol is selected from one or more of the following: methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol, pentanol, isopentanol, hexanol, isohexanol, heptanol, isoheptanol, octanol, isooctanol, nonanol, isononanol, decanol, isodecanol;

the olefin is selected from one or more than two of the following components: n-hexene, ethylene, n-butene, n-pentene, isopentene, isohexene, propylene, n-heptene, isoheptene, n-octene, isooctene, isobutylene, n-nonene, isononyl ene, n-decene, isodecene, n-undecene, isoundecene, n-dodecene, isododecene.