WO2022105047A1 - Catalyst, and preparation method and use - Google Patents

Abstract

A quaternary phosphonium salt polymer loaded bimetallic monatomic catalyst, and a preparation method and a use. The quaternary phosphonium salt polymer loaded bimetallic monatomic catalyst comprises a first metallic active component, a second metallic active component, and a quaternary phosphonium salt polymer carrier; the first metallic active component and the second metallic active component are loaded on the quaternary phosphonium salt polymer carrier; the first metallic active component is a mononuclear complex of a first metal; the second metallic active component is a mononuclear complex of a second metal; the quaternary phosphonium salt polymer carrier is obtained by means of a quaternary phosphonium salt polymer; the quaternary phosphonium salt polymer is obtained by means of the polymerization reaction of a quaternary phosphonium salt containing a carbon-carbon double bond; the first metal is at least one selected from Rh, Ir, and Au; and the second metal is at least one selected from Ni, La, Ru, Co, and Mn. The quaternary phosphonium salt polymer loaded bimetallic monatomic catalyst has very high carbonylation activity and stability.

Description

Catalyst and preparation method and application technical field

The application relates to a quaternary phosphonium salt polymer-supported bimetal single-atom catalyst, a preparation method and an application, and belongs to the field of catalyst synthesis.

Background technique

Methyl acetate is gradually replacing acetone, butanone, ethyl acetate, cyclopentane, etc. internationally. Because it does not belong to the restricted use of organic pollutant emissions, it can meet the new environmental protection standards of paint, ink, resin, and adhesive factories. Hydrogenation of methyl acetate to ethanol is also one of the main ways of producing ethanol from coal. The preparation method mainly includes (1) direct esterification of acetic acid and methanol with sulfuric acid as a catalyst to generate crude methyl acetate, then dehydration with calcium chloride, neutralization with sodium carbonate, and fractionation to obtain the finished methyl acetate. (2) Dimethyl ether was synthesized by carbonylation on H-MOR molecular sieve catalyst, but the molecular sieve was seriously deactivated by carbon deposition and the space-time yield was low. (3) When methanol carbonylation is used to prepare acetic acid, methyl acetate exists as a by-product, but the selectivity is low and the separation cost is high. Therefore, most of the currently industrially feasible synthetic routes of methyl acetate go through the intermediate step of acetic acid.

At present, the methanol carbonylation process is dominant in the industrial production of acetic acid. In this process, a homogeneous catalyst is commonly used in the prior art. Since the homogeneous catalyst itself has shortcomings such as easy loss of active components and difficulty in separation, so Some researchers have turned their attention to supported heterogeneous catalytic systems. The heterogeneous catalytic system can achieve the characteristics of convenient separation of catalyst and product, and the catalyst concentration is not limited by solubility. The production capacity can be improved by increasing the catalyst concentration. Supported heterogeneous catalytic systems can be roughly divided into polymer supports, activated carbon supports, inorganic oxide supports and other systems according to different supports. However, supported catalyst systems have lower activity than homogeneous catalytic systems, easy removal of active components, Higher requirements for the carrier and other issues.

In the prior art, the applications of polymers in methanol carbonylation are relatively few and immature at present. It has been reported that modified phosphine ligands can be used for methanol carbonylation, but the stability is poor due to less anchoring ligands. At present, for the methanol carbonylation reaction system, the most important thing is to find a ligand with good stability or a phosphine salt polymer containing ionic bonds, and at the same time, there must be enough metal points on the polymer that can anchor the metal. (coordination site or cationic site).

SUMMARY OF THE INVENTION

According to one aspect of the present application, there is provided a quaternary phosphonium salt polymer-supported bimetal single-atom catalyst for the heterogeneous carbonylation of methanol to produce methyl acetate and acetic acid, and the polymer support is not only associated with a metal mononuclear complex ( There is a strong coordination bond between organic complexes), and more importantly, the polymer carrier forms an ionic bond through the skeleton positive phosphonium and the metal mononuclear anion complex (inorganic complex), so that the metal mononuclear complex (inorganic complex) forms an ionic bond. Dispersion of atoms, large specific surface area of the carrier, and excellent thermal stability enable it to meet the reaction conditions required for heterogeneous carbonylation. The quaternary phosphonium salt polymer supported bimetallic single-atom catalyst has high carbonylation activity and stability.

A quaternary phosphonium salt polymer-supported bimetal single-atom catalyst, the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst comprises a first metal active component, a second metal active component and a quaternary phosphonium salt polymer carrier; the The first metal active component and the second metal active component are supported on the quaternary phosphonium salt polymer carrier; wherein, the first metal active component is a mononuclear complex of metal I; the second metal active component is The metal active component is a mononuclear complex of metal II; the quaternary phosphonium salt polymer carrier is obtained by a quaternary phosphonium salt polymer; the quaternary phosphonium salt polymer is obtained from a quaternary phosphonium salt containing a carbon-carbon double bond through a polymerization reaction obtained; the metal I is selected from at least one of Rh, Ir, and Au; the metal II is selected from at least one of Ni, La, Ru, Co, and Mn.

The mononuclear complex of the metal I is obtained by the metal I complex;

The mononuclear complex of the metal II is obtained by the metal II complex.

Specifically, the mononuclear complex of metal I can be a mononuclear inorganic complex of metal I, or it can be a mononuclear organic complex of metal I. The mononuclear complex of metal II is a mononuclear inorganic complex of metal II. The organic complex is coordinated with the P ligand in the carrier through a coordination bond, and the inorganic complex is an anionic complex, which is connected with the valent phosphonium in the polymer carrier skeleton through an ionic bond.

Metal monoatomic means that the metal is distributed in the form of a single nucleus.

Preferably, the metal I in the first metal active component is any one of Au and Ir; the metal II in the second metal active component is any one of Ru and La. At this time, the methyl acetate is collected in space and time. The rate can reach more than 4200.

Optionally, the quaternary phosphonium salt containing carbon-carbon double bond is selected from any one of the substances having the structural formula described in formula I;

Wherein, in formula I, R ₁ , R ₂ and R ₃ are independently selected from any one of groups containing carbon-carbon double bonds;

R ₄ is selected from any one of C ₁ -C ₅ alkyl and C ₆ -C ₁₀ aryl;

X is any one of F, Cl, Br, and I.

Optionally, in formula I, R ₁ , R ₂ and R ₃ are independently selected from any one of C ₂ -C ₁₅ groups containing carbon-carbon double bonds.

Optionally, the group containing the carbon-carbon double bond is selected from any one of the groups having the structural formula shown in formula II;

Wherein, in formula II, m is 0 or 1, and n is 0 or 1;

R ₅ is selected from any one of C ₁ -C ₅ alkylene groups.

Optionally, the quaternary phosphonium salt containing carbon-carbon double bond includes tris(4-vinylphenyl) phosphine methyl iodide, tris(4-vinylphenyl) phosphine ethyl iodide, tris(4-vinyl phenyl) Phenyl) phosphine phenyl iodide, tris (4-propenyl phenyl) phosphine methyl iodide, tris (4-butenyl phenyl) phosphine methyl iodide, tris (4-propenyl phenyl) phosphine ethyl iodide , tris (4-propenyl phenyl) phosphine phenyl iodide, tris (4-butenyl phenyl) phosphine phenyl iodide, tripropenyl phosphine methyl iodide, tripropenyl phosphine ethyl iodide, tripropenyl phosphine Any of phenyl iodide, tributenyl phosphine methyl iodide, and tripentenyl phosphine methyl iodide.

Tris(4-vinylphenyl)phosphine methyl iodide has the following structural formula

Optionally, the quaternary phosphonium salt polymer has a hierarchical pore structure including macropores, mesopores and micropores.

Optionally, the pore volume of the quaternary phosphonium salt polymer is 0.1-5.0 cm ³ /g; the specific surface area is 300-3000 m ² /g; and the average pore diameter is 0.2-50.0 nm.

Optionally, the first metal active component and the second metal active component are supported on a quaternary phosphonium salt polymer carrier through ionic bonds and/or coordinate bonds.

Specifically, the first metal active component and the second metal active component are supported on a quaternary phosphonium salt polymer carrier through ionic bonds and coordination bonds, or the first metal active component and the second metal active component The fractions are supported on the quaternary phosphonium salt polymer carrier by ionic bonds.

Optionally, the content of the first metal active component in the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst is 0.01-5.0 wt %; the second metal active component is contained in the quaternary phosphonium salt The content of the polymer-supported bimetal single-atom catalyst is 0.1-10 wt%;

Wherein, the mass of the first metal active component is based on the mass of metal I; the mass of the second metal active component is based on the mass of metal II; the mass of the quaternary phosphonium salt polymer supported bimetallic single-atom catalyst is based on Mass meter for quaternary phosphonium salt polymers.

Preferably, the content of the first metal active component in the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst is 0.1-2.0 wt %.

Preferably, the content of the first metal active component in the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst is 0.3-1.0 wt%

Preferably, the content of the second metal active component in the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst is 0.1-4.0 wt %.

Preferably, the content of the second metal active component in the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst is 0.2-1.0 wt %.

Optionally, the molar ratio of the first metal active component to the second metal active component is 0.1 to 10; the molar amount of the first metal active component is based on the molar amount of metal I; the The molar amount of the second metal active component is based on the molar amount of metal II.

According to another aspect of the present application, there is also provided a preparation method of the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst described in any of the above, the preparation method comprising:

S100, obtaining a quaternary phosphonium salt polymer;

S200, the metal I complex and the metal II complex are supported on the quaternary phosphonium salt polymer to obtain the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst.

Optionally, the step S100 includes:

The mixture containing an initiator, a quaternary phosphonium salt containing a carbon-carbon double bond, and an organic solvent a is subjected to solvothermal polymerization to obtain a solution a containing the quaternary phosphonium salt polymer;

The quaternary phosphonium salt polymer can be obtained by removing the solvent in the solution a.

Optionally, the initiator is selected from one or more of cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl hydroperoxide, azobisisobutyronitrile, and azobisisoheptanenitrile .

Optionally, the organic solvent a is selected from one or more of benzene, toluene, dichloromethane, tetrahydrofuran, methanol, dimethylformamide, and chloroform.

Optionally, the mass ratio of the carbon-carbon double bond-containing quaternary phosphonium salt to the initiator is 0.5-100:1.

Specifically, the upper limit of the mass ratio of the quaternary phosphonium salt containing carbon-carbon double bond to the initiator is 1:1, 10:1, 20:1, 40:1, 60:1, 80:1, 100:1; containing The lower limit of the mass ratio of the quaternary phosphonium salt of the carbon-carbon double bond to the initiator is 0.5:1, 1:1, 10:1, 20:1, 40:1, 60:1, 80:1.

Preferably, the mass ratio of the carbon-carbon double bond-containing quaternary phosphonium salt to the initiator is 30-50:1.

More preferably, the mass ratio of the carbon-carbon double bond-containing quaternary phosphonium salt to the initiator is 40:1.

Optionally, the conditions of the solvothermal polymerization: the reaction temperature is 80-200° C.; the reaction time is 1-100 hours.

Specifically, the upper limit of the reaction temperature is selected from 100°C, 150°C, and 200°C; the lower limit of the reaction temperature is selected from 80°C, 100°C, and 150°C.

The upper limit of the reaction time is selected from 12h, 24h, 36h, 48h, 60h, 80h, 100h; the lower limit of the reaction time is selected from 1h, 12h, 24h, 36h, 48h, 60h, 80h.

Preferably, the reaction temperature is 80-120° C.; and the reaction time is 20-30 h.

More preferably, the reaction temperature is 100°C; the reaction time is 24h.

Specifically, the step S100 includes:

a) Mix the quaternary phosphonium salt (monomer) of carbon-carbon double bond with organic solvent a under the protection of inert atmosphere at 0℃～200℃, then add free radical initiator, and stir the obtained mixed solution for 0.1～100 ℃ Hour,

b) under the protection of 0 ℃～200 ℃ and inert atmosphere, transfer the mixed solution to the hydrothermal kettle and stand for 1～100 hours under the condition of solvothermal polymerization to carry out the polymerization reaction,

c) The reaction mixture obtained in step b) is vacuumed to remove the solvent at room temperature, thereby obtaining a quaternary phosphonium salt polymer with a large surface area and a hierarchical pore structure.

Optionally, the step S200 includes:

S200-a, loading the metal I complex on the quaternary phosphonium salt polymer to obtain an intermediate product;

S200-b, obtain metal II complex;

S200-c, loading the metal II complex on the intermediate product to obtain the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst;

Wherein, in step S200-a, the metal I complex includes any one of metal I carbonyl chloride and metal I acetylacetone complex.

Specifically, the carbonyl chloride of metal I includes any one of Rh ₂ (CO) ₄ Cl ₂ and Ir(CO) ₃ Cl.

The acetylacetone complex of metal I includes any one of Rh(CO)C ₅ H ₇ O ₂ and Ir(CO)C ₅ H ₇ O ₂ .

In step 200-b, the metal II complex is a metal II anion complex.

Optionally, the step S200-a includes: dissolving the metal I complex in the organic solvent b at 0 to 200° C. under the protection of an inactive atmosphere, then adding the quaternary phosphonium salt polymer, stirring , remove the organic solvent b, and then the intermediate product can be obtained.

Optionally, in step S200-a, the organic solvent b is selected from one or more of benzene, toluene, dichloromethane, tetrahydrofuran, methanol, ethanol, dimethylformamide, and chloroform.

Optionally, in step S200-a, the mass ratio of the metal I complex to the quaternary phosphonium salt polymer is 0.01-0.05.

Specifically, the upper limit of the mass ratio of the metal I complex to the quaternary phosphonium salt polymer is selected from 0.015, 0.0285, 0.04, and 0.05; the lower limit of the mass ratio of the metal I complex to the quaternary phosphonium salt polymer is selected from From 0.01, 0.015, 0.0285, 0.04.

Optionally, step S200-b includes: subjecting the mixed solution containing the metal II precursor and the solvent c to a complexation reaction to obtain a solution containing the metal II complex.

Optionally, the metal II precursor includes at least one of chloride of metal II and nitrate of metal II.

Specifically, the chloride of metal II includes any one of NiCl ₂ , LaCl ₃ , RuCl ₃ , MnCl ₂ , and CoCl ₂ .

The nitrate of metal II includes any one of Ni(NO ₃ ) ₂ , La(NO ₃ ) ₃ , Mn(NO ₃ ) ₂ , and Co(NO ₃ ) ₂ .

The metal II precursor and solvent c undergo complex reaction to obtain an anion complex. For example, NiCl ₂ is complexed with concentrated hydrochloric acid to obtain NiCl ₄ ^2- complex ion.

Optionally, the solvent c includes any one of concentrated hydrochloric acid and nitric acid;

Wherein, the mass fraction of the concentrated hydrochloric acid is 36-38%.

Optionally, the ratio relationship between the metal II precursor and the solvent c is 0.1:15-25 g/ml.

The upper limit of the ratio relationship between the metal II precursor and the solvent c is selected from 0.1:20g/ml, 0.1:25g/ml; the lower limit of the ratio relationship between the metal II precursor and the solvent c is selected from 0.1:15g/ml, 0.1:20g/ml.

Optionally, step S200-c includes:

The intermediate product is immersed in the solution containing the metal II complex to obtain the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst;

The mass ratio of the metal II complex to the intermediate product is 0.005-0.02;

Wherein, the mass of the metal II complex is based on the mass of the metal II precursor;

The mass of the intermediate product is based on the mass of the quaternary phosphonium salt polymer.

Specifically, the ratio of the intermediate product to the solution containing the metal II complex is 8-12 g: 20 ml.

Specifically, the upper limit of the mass ratio of the metal II complex to the intermediate product is 0.01, 0.02; the lower limit of the mass ratio of the metal II complex to the intermediate product is 0.005, 0.01.

Optionally, the step S200 includes:

S200-i, obtaining a solution containing metal I complex and metal II complex;

S200-ii, adding the quaternary phosphonium salt polymer to the solution in step S200-i, loading, to obtain the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst;

Wherein, in step 200-i, the metal I complex is a metal I anion complex; the metal II complex is a metal II anion complex.

Optionally, the step S200-i includes:

The solution containing the metal I complex and the metal II complex can be obtained by mixing the metal I precursor and the metal II precursor with the solvent d, and performing a complexation reaction.

Optionally, the metal I precursor includes at least one of metal I chloride and metal I nitrate.

Specifically, the chloride of metal I includes any one of HAuCl ₄ , H ₂ IrCl ₆ , IrCl ₃ , and RhCl ₃ .

Metal I nitrates include Rh( _NO3 ) ₃ .

The metal II precursor includes at least one of metal II chloride and metal II nitrate.

Specifically, the chloride of metal II and the nitrate of metal II are as described above, and will not be repeated here.

Optionally, the solvent d includes any one in concentrated hydrochloric acid and nitric acid;

Wherein, the mass fraction of the concentrated hydrochloric acid is 36-38%.

Optionally, the ratio relationship between the metal I precursor, the metal II precursor and the solvent d is 0.1-0.3 g: 0.05-0.2 g: 15-25 ml.

Optionally, in the step S200-ii, the ratio of the quaternary phosphonium salt polymer to the metal I precursor and the metal II precursor is 8-12 g: 0.1-0.3 g: 0.05-0.2 g.

The catalyst formed by two metal mononuclear anion complexes (inorganic complexes) has higher activity in the methanol heterogeneous carbonylation reaction, and the space-time yield can reach more than 5600.

According to the third aspect of the present application, there are also provided the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst described in any of the above, and the quaternary phosphonium salt polymer-supported bimetallic mono-atom catalyst obtained by the preparation method described in any of the above Application of atomic catalysts in methanol carbonylation to produce methyl acetate and acetic acid.

According to the fourth aspect of the present application, there is also provided a method for preparing methyl acetate and acetic acid by heterogeneous methanol carbonylation, the method comprising: contacting and reacting raw materials containing methanol and CO with a catalyst to obtain acetic acid methyl ester and acetic acid;

The catalyst is selected from any of the quaternary phosphonium salt polymer-supported bimetal single-atom catalysts described in any one of the above and the quaternary phosphonium salt polymer-supported bimetal single-atom catalysts obtained by the preparation method described in any of the above kind.

Optionally, the reaction conditions are: the reaction temperature is 130-250° C.; and the reaction pressure is 0.5-3.5 MPa.

Optionally, a cocatalyst is also included in the reaction process;

The cocatalyst includes any one of methyl iodide and methyl bromide.

Optionally, the added amount of the cocatalyst is 1-40.0 wt % of methanol.

Optionally, the liquid volume space velocity is 0.1-15 h ⁻¹ ; the liquid is a mixture of methanol and a cocatalyst;

The molar ratio of CO to methanol is 1-2.

In this application, the subscripts in C ₁ -C ₅ , C ₂ -C ₁₅ , C ₆ -C ₁₀ represent the number of carbon atoms contained in the group, for example, C ₅ alkyl refers to an alkyl group with 5 carbon atoms ;

"Alkylene" means a group formed by the loss of any two hydrogen atoms on the molecule of an alkane compound;

"Arylene" refers to a group formed by the loss of any two hydrogen atoms on the aromatic ring of an aromatic hydrocarbon molecule.

The beneficial effects that this application can produce include:

Compared with the existing supported rhodium or iridium-based agent methanol carbonylation technology, the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst of the present invention has higher activity in the methanol heterogeneous carbonylation reaction (the space-time yield can be increase by 26% to 180%) and have extremely high stability.

Description of drawings

Figure 1 is the physical adsorption characterization of the catalyst in Example 1 of the application.

FIG. 2 is the single-atom characterization of the catalyst in Example 1 of the present application by spherical aberration electron microscope.

Fig. 3 is the application test result of the catalyst in Example 1 of the application in methanol gas phase carbonylation reaction.

Detailed ways

The present application will be described in detail below with reference to the examples, but the present application is not limited to these examples.

Unless otherwise specified, the raw materials in the examples of this application are all purchased through commercial channels.

Possible implementations are described below:

A bimetallic single-atom catalyst supported by a quaternary phosphonium salt polymer for preparing methyl acetate and acetic acid by carbonylation of methanol and a preparation method thereof. The catalyst is composed of three parts: main active component, auxiliary agent and carrier. The main active component is a mononuclear complex of Rh, Ir or Au, the auxiliary is a mononuclear complex of Ni, La, Ru, Co, Mn; the carrier is a phosphine-containing polymer, and its specific surface area is 300-3000m ² /g, and the average pore size is 0.2 to 50.0 nm.

The content of the main active component is 0.01-5.0% by weight of the catalyst; the auxiliary agent is a mononuclear complex of Ni, La, Ru, Co, and Mn, and its content is 0.1-10% by weight of the catalyst; and the main active component is The molar ratio of ingredients and auxiliary agents is 0.1 to 10; the metal precursor is selected from one or more of chlorides, carbonyl chlorides, nitrates, acetylacetone complexes, etc. The solvent used can be concentrated hydrochloric acid, dichloromethane One or more mixtures of , tetrahydrofuran or dimethylformamide.

Under the protective atmosphere of inert gas at 273-473K, in the solvent containing the metal precursor, add the polymer carrier; stir the obtained mixture solution for 0.1-100 hours; wash the obtained reaction mixture with the same solvent at room temperature , after suction filtration, the solvent is removed by vacuum, thereby obtaining a bimetallic single-atom catalyst supported by a quaternary phosphonium salt polymer.

Reactants such as CO and pumped methanol enter into a fixed bed reactor equipped with the catalyst of the present invention to carry out methanol carbonylation reaction, and the main products are methyl acetate and acetic acid.

The temperature of the carbonylation reaction is 130～250℃, 0.5～3.5MPa, and the liquid volume space velocity is 0.1～15h ^-1 .

The cocatalyst reactant also includes methyl iodide, which is 1 to 40.0% by weight of methanol.

The main reactor material used is Hastelloy.

A quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst for methanol carbonylation is used in the reaction of converting methanol/CO into methyl acetate and acetic acid.

The quaternary phosphonium salt polymer is preferably prepared by the following method:

First, in a three-necked round-bottomed flask equipped with a stirring and temperature control device under a protective atmosphere of 273-473 K and an inert gas such as nitrogen or argon, in a three-necked round-bottomed flask containing vinyl-functionalized triphenyl quaternary phosphonium salt phosphine monomer organic In the solvent, a free radical initiator is added, and the weight ratio of the monomer and the free radical initiator is 0.5:1 to 100:1. The resulting mixture solution is stirred for 0.1 to 100 hours. Preferably, the organic solvent used can be one or more mixtures of toluene, dichloromethane, tetrahydrofuran or dimethylformamide; the free radical initiator can be azobisisobutyronitrile or azobisisoheptane A type of nitrile. Next, the above mixture solution is transferred to a closed reactor such as a hydrothermal kettle, and the above solution is allowed to stand for 1 to 100 hours under 293-473 K and an inert gas such as nitrogen or argon protective atmosphere using a solvothermal polymerization method, thereby generating Desirable high surface area polymeric supports with multipolar porous structures. Finally, the above-mentioned polymerized reaction mixture is vacuumed to remove the solvent at room temperature to obtain a quaternary phosphonium salt polymer carrier with a high surface area and a multipolar porous structure.

Comparative Example 1

Under the protective atmosphere of 298K and _N2 , 10.0 g of tris(4-vinylphenyl)ylphosphine methyl iodide (manufacturer: Aladdin) was dissolved in 100.0 ml of dimethylformamide solvent as a monomer, and added to the above solution. 0.25 g of azobisisobutyronitrile as a radical initiator was added, and the mixture was stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. After the above-mentioned polymerized solution is cooled to room temperature, the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer carrier with a large surface area and a hierarchical porous structure formed by polymerization. Then, under the protective atmosphere of 298K and N ₂ , 0.285g of Ir(CO) ₃ Cl was dissolved in 50ml of CH ₃ CH ₂ OH, and 10g of polymer was added to it, stirred at room temperature for 24 h, washed with CH ₂ Cl ₂ and filtered with suction, The solvent was evacuated by vacuuming to obtain the Ir single-atom iridium-based catalyst supported on the quaternary phosphonium salt polymer, and the content of the Ir complex in the sample was 1.75 wt %.

Example 1

Under 298K and _N2 protective atmosphere, 10.0g tris(4-vinylphenyl)ylphosphine methyl iodide was dissolved as monomer in 100.0ml dimethylformamide solvent, and 0.25g was added to the above solution as free radical Initiator of azobisisobutyronitrile, stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. After the above-mentioned polymerized solution is cooled to room temperature, the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical porous structure formed by polymerization, which is recorded as carrier 1#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g Rh ₂ (CO) ₄ Cl ₂ was dissolved in 50ml CH ₂ Cl ₂ , and 10g polymer (carrier 1#) was added into it, stirred at room temperature for 24h, CH ₂ After Cl ₂ washing and suction filtration, the solvent was evacuated by vacuum to obtain an intermediate product.

Dissolve 0.1 g of NiCl ₂ in 20 ml of concentrated hydrochloric acid (concentration of 36 wt %), immerse the prepared sample (i.e. the intermediate product) in it, stir at room temperature for 24 h, wash with ethanol and suction filtration, and then vacuum dry at 90 °C to obtain quaternary phosphonium salt polymerization The Rh-Ni bimetallic single-atom catalyst supported by the material is denoted as sample 1#.

The content of the first metal active component Rh complex in sample 1# is 1.5wt%;

The content of the second metal active component Ni complex in sample 1# is 0.45wt%;

The molar ratio of Rh complex to Ni complex was 1.9.

The 1# catalyst in Example 1 was characterized by physical adsorption. The characterization results are shown in Figure 1. It can be seen from Figure 1(A) that the catalyst has a large specific surface area; from Figure 1(B), it can be seen that the catalyst has porous the physical structure of sex;

The 1# catalyst in Example 1 was characterized by spherical aberration electron microscope single atom, and the characterization result is shown in Figure 2. It can be seen from Figure 2 that the metals all exist in the form of single atoms.

Example 2

Under the protective atmosphere of 298K and _N2 , 10.0 g of tris(4-vinylphenyl)ylphosphine ethyl iodide (manufacturer: Aladdin) was dissolved in 100.0 ml of dimethylformamide solvent as a monomer, and added to the above solution. 0.25 g of azobisisobutyronitrile as a radical initiator was added, and the mixture was stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical porous structure formed by polymerization, which is denoted as carrier 2#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g of Ir(CO) ₃ Cl was dissolved in 50ml of CH ₃ CH ₂ OH, and 10g of polymer (carrier 2#) was added to it, stirred at room temperature for 24h, CH ₂ Cl ₂ After washing and suction filtration, the solvent was evacuated by vacuum to obtain an intermediate product.

Dissolve 0.1 g of NiCl ₂ in 20 ml of concentrated hydrochloric acid (concentration of 36 wt %), immerse the prepared sample (i.e. the intermediate product) in it, stir at room temperature for 24 h, wash with ethanol and suction filtration, and then vacuum dry at 90 °C to obtain quaternary phosphonium salt polymerization The supported IrNi bimetallic single-atom catalyst is denoted as sample 2#.

The content of the first metal active component Ir complex in sample 2# is 1.75wt%;

The content of the second metal active component Ni complex in sample 2# is 0.44wt%.

Example 3

Under the protective atmosphere of 298K and _N2 , 10.0 g of tris(4-vinylphenyl) phosphine phenyl iodide (manufacturer: Aladdin) was dissolved in 100.0 ml of dimethylformamide solvent as a monomer, and added to the above solution. 0.25 g of azobisisobutyronitrile as a radical initiator was added, and the mixture was stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical pore structure formed by polymerization, which is denoted as carrier 3#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g of Ir(CO) ₃ Cl was dissolved in 50ml of CH ₃ CH ₂ OH, and 10g of polymer (carrier 3#) was added to it, stirred at room temperature for 24h, CH ₂ Cl ₂ After washing and suction filtration, the solvent was evacuated by vacuum to obtain an intermediate product.

Dissolve 0.1 g of LaCl ₃ in 20 ml of concentrated hydrochloric acid (concentration of 36 wt%), immerse the above prepared sample (i.e. intermediate product) in it, stir at room temperature for 24 h, wash with ethanol and suction filtration, and vacuum dry at 90 ° C to obtain quaternary phosphonium salt polymerization The supported IrLa bimetallic single-atom catalyst was recorded as sample 3#.

The content of the first metal active component Ir complex in sample 3# is 1.75wt%;

The content of the second metal active component La complex in sample 3# is 0.56 wt %.

Example 4

Under the protective atmosphere of 298K and _N2 , 10.0 g of tris(4-propenylphenyl)ylphosphine methyl iodide (manufacturer: Aladdin) was dissolved as a monomer in 100.0 ml of dimethylformamide solvent, and added to the above solution. 0.25 g of azobisisobutyronitrile as a radical initiator was added, and the mixture was stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a multi-level porous structure formed by polymerization, which is denoted as carrier 4#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g of Ir(CO) ₃ Cl was dissolved in 50ml of CH ₃ CH ₂ OH, and 10g of polymer (ie carrier 4#) was added to it, stirred at room temperature for 24h, CH ₂ Cl ₂ After washing and suction filtration, the solvent is removed by vacuuming to obtain an intermediate product.

Dissolve 0.1 g of RuCl ₃ in 20 ml of concentrated hydrochloric acid (concentration of 38 wt %), immerse the prepared sample (i.e. the intermediate product) in it, stir at room temperature for 24 h, wash with ethanol and suction filtration, and then vacuum dry at 90 °C to obtain quaternary phosphonium salt polymerization The supported Ir-Ru bimetallic single-atom catalyst is denoted as sample 4#.

The content of the first metal active component Ir complex in sample 4# is 1.75wt%;

The content of the second metal active component Ru complex in sample 4# is 0.48 wt %.

Example 5

Under the protective atmosphere of 298K and _N2 , 10.0 g of tris(4-butenylphenyl)ylphosphine methyl iodide (manufacturer: Aladdin) was dissolved in 100.0 ml of dimethylformamide solvent as a monomer, and added to the above solution. 0.25 g of azobisisobutyronitrile as a radical initiator was added thereto, and the mixture was stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. After the above-mentioned polymerized solution is cooled to room temperature, the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a multi-level porous structure formed by polymerization, which is denoted as carrier 5#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g Rh ₂ (CO) ₄ Cl ₂ was dissolved in 50ml CH ₃ CH ₂ OH, and 10g polymer (ie, carrier 5#) was added to it, and stirred at room temperature for 24h, After washing with CH ₂ Cl ₂ and suction filtration, the solvent was evacuated by vacuum to obtain an intermediate product.

Dissolve 0.1 g of LaCl ₃ in 20 ml of concentrated hydrochloric acid (concentration of 38 wt%), immerse the above-prepared sample (i.e. intermediate product) in it, stir at room temperature for 24 h, wash with ethanol, suction filtration, and vacuum dry at 90 ° C to obtain quaternary phosphonium salt polymerization The Rh-La bimetallic single-atom catalyst supported by the material is denoted as sample 5#.

The content of the first metal active component Rh complex in sample 5# is 1.50wt%;

The content of the second metal active component La complex in sample 5# is 0.56wt%.

Example 6

Under the protective atmosphere of 298K and _N2 , 10.0 g of tris(4-propenylphenyl)ylphosphinoethyl iodide (manufacturer: Aladdin) was dissolved in 100.0 ml of dimethylformamide solvent as a monomer, and added to the above solution. 0.25 g of azobisisobutyronitrile as a radical initiator was added, and the mixture was stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. After the above-mentioned polymerized solution is cooled to room temperature, the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a multi-level porous structure formed by polymerization, which is denoted as carrier 6#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g Rh ₂ (CO) ₄ Cl ₂ was dissolved in 50ml CH ₃ CH ₂ OH, and 10g polymer (ie, carrier 6#) was added into it, and stirred at room temperature for 24h, After washing with CH ₂ Cl ₂ and suction filtration, the solvent was evacuated by vacuum to obtain an intermediate product.

Dissolve 0.1 g MnCl ₂ in 20 ml of concentrated hydrochloric acid (concentration is 36 wt %), immerse the above prepared sample (i.e. intermediate product) in it, stir at room temperature for 24 h, wash with ethanol and suction filtration, and dry at 90 ° C under vacuum to obtain quaternary phosphonium salt polymerization The RhMn bimetallic single-atom catalyst supported by the material is denoted as sample 6#.

The content of the first metal active component Rh complex in sample 6# is 1.50wt%;

The content of the second metal active component Mn complex in sample 6# is 3.45wt%.

Example 7

Under the protective atmosphere of 298K and _N2 , 10.0g of tris(4-propenylphenyl)ylphosphinophenyl iodide was dissolved as monomer in 100.0ml of dimethylformamide solvent, and 0.25g was added to the above solution as free radical Initiator of azobisisobutyronitrile, stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a multi-level porous structure formed by polymerization, which is denoted as carrier 7#.

Then, under the protective atmosphere of 298K and N ₂ , 0.285g Rh ₂ (CO) ₄ Cl ₂ was dissolved in 50ml CH ₃ CH ₂ OH, and 10g polymer (namely carrier 7#) was added into it, and stirred at room temperature for 24h, After washing with CH ₂ Cl ₂ and suction filtration, the solvent was evacuated by vacuum to obtain an intermediate product.

Dissolve 0.1 g of CoCl ₂ in 20 ml of concentrated hydrochloric acid (concentration of 37 wt %), immerse the prepared sample (i.e. the intermediate product) in it, stir at room temperature for 24 h, wash with ethanol and suction filtration, and then vacuum dry at 90 ° C to obtain quaternary phosphonium salt polymerization The RhCo bimetallic single-atom catalyst supported by the material is denoted as sample 7#.

The content of the first metal active component Rh complex in sample 7# is 1.50wt%;

The content of the second metal active component Co complex in sample 7# is 4.54wt%.

Example 8

Under the protective atmosphere of 298K and _N2 , 10.0g of tris(4-butenylphenyl)ylphosphinophenyl iodide was dissolved as monomer in 100.0ml of dimethylformamide solvent, and 0.25g was added to the above solution as free azobisisobutyronitrile based initiator and stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a multi-level porous structure formed by polymerization, which is denoted as carrier 8#.

Dissolve 0.285g HAuCl ₄ and 0.1g LaCl ₃ in 20ml of concentrated hydrochloric acid (concentration is 36wt%), add 10g of polymer (i.e. carrier 8#) into it, stir at room temperature for 24h, wash with ethanol and suction filter, and dry at 90°C under vacuum. The Au-La bimetallic single-atom catalyst supported by the quaternary phosphonium salt polymer was obtained, which was recorded as sample 8#.

The content of the first metal active component Au complex in sample 8# is 1.12wt%;

The content of the second metal active component La complex in sample 8# is 0.56wt%.

Example 9

Under the protective atmosphere of 298K and _N2 , 10.0g of tripropenylphosphine methyl iodide was dissolved as a monomer in 100.0ml of dimethylformamide solvent, and 0.25g of azobis as a radical initiator was added to the above solution. isobutyronitrile, stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical porous structure formed by polymerization, which is denoted as carrier 9#.

Dissolve 0.285g HAuCl ₄ and 0.1g RuCl ₃ in 20ml of concentrated hydrochloric acid (concentration is 36wt%), add 10g of polymer (carrier 9#) into it, stir at room temperature for 24h, wash with ethanol and suction filter, and vacuum dry at 90°C to obtain The Au-Ru bimetallic single-atom catalyst supported by the quaternary phosphonium salt polymer is recorded as sample 9#.

The content of the first metal active component Au complex in sample 9# is 1.12wt%;

The content of the second metal active component Ru complex in sample 9# was 0.48 wt %.

Example 10

Under the protective atmosphere of 298K and _N2 , 10.0g of tripropenylphosphine ethyl iodide (manufacturer: Aladdin) was dissolved in 100.0ml of dimethylformamide solvent as a monomer, and 0.25g was added to the above solution as a free radical Initiator of azobisisobutyronitrile, stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution was cooled to room temperature, and the solvent was vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical porous structure formed by polymerization, which was recorded as carrier 10#.

Dissolve 0.285g HAuCl ₄ and 0.1g NiCl ₂ in 20ml of concentrated hydrochloric acid (concentration is 37wt%), add 10g of polymer (i.e. carrier 10#) into it, stir at room temperature for 24h, wash with ethanol and suction filter, and dry at 90°C under vacuum. The Au-Ni bimetallic single-atom catalyst supported by the quaternary phosphonium salt polymer was obtained, which was recorded as sample 10#.

The content of the first metal active component Au complex in sample 10# is 1.12wt%;

The content of the second metal active component Ni complex in sample 10# is 0.45wt%.

Example 11

Under the protective atmosphere of 298K and _N2 , 10.0g tripropenylphosphine phenyl iodide (manufacturer: Aladdin) was dissolved in 100.0ml dimethylformamide solvent as a monomer, and 0.25g was added to the above solution as a free radical Initiator of azobisisobutyronitrile, stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical porous structure formed by polymerization, which is denoted as carrier 11#.

Dissolve _{0.285g of} IrCl and 0.1g of LaCl in 20ml of concentrated hydrochloric acid (concentration of 38wt%), add 10g of polymer (i.e. carrier 11#) into it, stir at room temperature for 24h, wash with ethanol and suction and filter, and dry at 90°C under vacuum. The Ir-La bimetallic single-atom catalyst supported by the quaternary phosphonium salt polymer was obtained, which was recorded as sample 11#.

The content of the first metal active component Ir complex in sample 11# is 1.75wt%;

The content of the second metal active component La complex in Sample 11# is 0.56 wt %.

Example 12

Under 298K and _N2 protective atmosphere, 10.0g of tributenylphosphine methyl iodide (manufacturer: Aladdin) was dissolved in 100.0ml of dimethylformamide solvent as a monomer, and 0.25g was added to the above solution as free azobisisobutyronitrile based initiator and stirred for 2 hours. The stirred solution was moved to a hydrothermal kettle and polymerized by solvothermal polymerization method at 373K and nitrogen gas protective atmosphere for 24h. The above-mentioned polymerized solution is cooled to room temperature, and the solvent is vacuumed away at room temperature to obtain a quaternary phosphonium salt polymer with a large surface area and a hierarchical porous structure formed by polymerization, which is recorded as carrier 12#.

Dissolve _{0.285g of} IrCl and 0.1g of RuCl in 20ml of concentrated hydrochloric acid (concentration of 36wt%), add 10g of polymer (i.e. carrier 12#) into it, stir at room temperature for 24h, wash with ethanol and suction and filter, and dry at 90°C under vacuum. The Ir-Ru bimetallic single-atom catalyst supported by the quaternary phosphonium salt polymer was obtained, which was recorded as sample 12#.

The content of the first metal active component Ir complex in sample 12# is 1.75wt%;

The content of the second metal active component Ru complex in sample 12# is 0.48 wt %.

Example 13 Characterization of Quaternary Phosphonium Salt Polymers

Physical adsorption characterization of quaternary phosphonium salt polymer-supported bimetallic single-atom catalysts

The quaternary phosphonium salt polymer samples in Examples 1-12 were respectively subjected to specific surface area test and pore size test on the Autosorb-1 adsorption analyzer of Quantachrome Instruments. Before the test, the samples were pretreated at 373K for 20 hours. The test results show that the specific surface area of the quaternary phosphonium salt polymer is 300-3000 m ² /g; the average pore size is 0.2-50.0 nm.

Taking the quaternary phosphonium salt polymer in Example 1 as an example, the test results: the specific surface area of the quaternary phosphonium salt polymer is 1200 m ² /g; the average pore size is 1.26 nm.

Application example: the application of the prepared catalyst in the reaction of preparing methyl acetate and acetic acid with methanol/CO as raw material.

The reaction conditions are: 200° C., 2.5MPa, CH ₃ OH/CO=1:1.5 (molar ratio), CH ₃ OH/CH ₃ I (mass ratio)=8:1, liquid feed rate 0.05ml/min ( The liquid volume space velocity is 6.0h ^-1 ), and the catalyst mass is 0.1000g. After the reaction tail gas was cooled by a cold trap, the gas phase product was analyzed online. The chromatographic instrument was Agilent 7890A GC, PQ packed column, and TCD detector. Off-line analysis of liquid products, FFAP capillary column, FID detector. Internal standard method analysis, isobutanol as the internal standard.

Use the catalyst supported by the quaternary phosphonium salt polymer carrier prepared in Comparative Example 1 and Example 1-12, prepare methyl acetate and acetic acid according to the above-mentioned operations, and the carbonylation activity, the selectivity of methyl acetate and the selectivity of acetic acid are as shown in Table 1 , the data is tested after 100h. The data of Example 1 is shown in FIG. 3 .

Table 1 embodiment methanol carbonylation reaction results summary

Wherein, acetic acid selectivity=moles of acetic acid/(moles of acetic acid+moles of methyl acetate);

Methyl acetate selectivity=moles of methyl acetate/(moles of acetic acid+moles of methyl acetate);

Space-time yield=(moles of acetic acid+moles of methyl acetate)/(moles of the first metal supported by the quaternary phosphorus salt polymer)/reaction time.

The results show that: through the comparison of Examples 1-12 and Comparative Example 1, it is known that the activity (i.e., the space yield) of the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst is much better than that of the quaternary phosphonium salt polymer-supported single-atom catalyst. .

The above are only a few embodiments of the present application, and are not intended to limit the present application in any form. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Without departing from the scope of the technical solution of the present application, any changes or modifications made by using the technical content disclosed above are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims (32)

1. A quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst, characterized in that the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst comprises a first metal active component, a second metal active component and a quaternary phosphonium salt polymerization material carrier;

   The first metal active component and the second metal active component are supported on the quaternary phosphonium salt polymer carrier;

   Wherein, the first metal active component is a mononuclear complex of metal I;

   The second metal active component is a mononuclear complex of metal II;

   The metal I is selected from at least one of Rh, Ir, and Au;

   The metal II is selected from at least one of Ni, La, Ru, Co, and Mn.
2. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 1, wherein the quaternary phosphonium salt polymer support is obtained by a quaternary phosphonium salt polymer; Quaternary phosphonium salts of double bonds are obtained by polymerization.
3. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 2, wherein the quaternary phosphonium salt containing carbon-carbon double bond is selected from any one of the substances having the structural formula described in formula I;

   

   Wherein, in formula I, R ₁ , R ₂ and R ₃ are independently selected from any one of C ₂ -C ₁₅ groups containing carbon-carbon double bonds;

   R ₄ is selected from any one of C ₁ -C ₅ alkyl and C ₆ -C ₁₀ aryl;

   X is any one of F, Cl, Br, and I.
4. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 3, wherein the C ₂ to C ₁₅ groups containing carbon-carbon double bonds are selected from groups having the structural formula shown in formula II any of the;

   

   Wherein, in formula II, m is 0 or 1, and n is 0 or 1;

   R ₅ is selected from any one of C ₁ -C ₅ alkylene groups.
5. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 2, wherein the quaternary phosphonium salt containing carbon-carbon double bonds comprises tris(4-vinylphenyl) phosphine methyl iodide, tris(4-vinylphenyl) phosphine methyl iodide, (4-Vinylphenyl)ylphosphine ethyl iodide, Tris(4-vinylphenyl)ylphosphine phenyl iodide, Tris(4-propenylphenyl)ylphosphine methyl iodide, Tris(4-butenylbenzene) phosphine methyl iodide, tris (4-propenyl phenyl) phosphine ethyl iodide, tris (4-propenyl phenyl) phosphine phenyl iodide, tris (4-butenyl phenyl) phosphine phenyl iodide, tris (4-butenyl phenyl) phosphine phenyl iodide, Any of propenyl phosphine methyl iodide, tripropenyl phosphine ethyl iodide, tripropenyl phosphine phenyl iodide, tributenyl phosphine methyl iodide, and tripentenyl phosphine methyl iodide.
6. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 1, wherein the quaternary phosphonium salt polymer has a hierarchical pore structure including macropores, mesopores and micropores.
7. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 1, wherein the quaternary phosphonium salt polymer has a pore volume of 0.1-5.0 cm ³ /g, and a specific surface area of 300-3000 m ² / g; the average pore size is 0.2 to 50.0 nm.
8. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 1, wherein the first metal active component and the second metal active component are supported on the quaternary through ionic bonds and/or coordination bonds on a phosphonium salt polymer carrier.
9. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 1, wherein the content of the first metal active component in the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst is 0.01 ~5.0wt%;

   The content of the second metal active component in the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst is 0.1-10 wt%;

   Wherein, the mass of the first metal active component is based on the mass of metal I;

   The mass of the second metal active component is based on the mass of metal II;

   The mass of the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst is based on the mass of the quaternary phosphonium salt polymer.
10. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to claim 1, wherein the molar ratio of the first metal active component to the second metal active component is 0.1-10;

    The molar amount of the first metal active component is based on the molar amount of metal I;

    The molar amount of the second metal active component is based on the molar amount of metal II.
11. The preparation method of the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to any one of claims 1 to 10, wherein the preparation method comprises:

    S100, obtaining a quaternary phosphonium salt polymer;

    S200, the metal I complex and the metal II complex are supported on the quaternary phosphonium salt polymer to obtain the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst.
12. The preparation method according to claim 11, wherein the step S200 comprises:

    S200-a, loading the metal I complex on the quaternary phosphonium salt polymer to obtain an intermediate product;

    S200-b, obtain metal II complex;

    S200-c, loading the metal II complex on the intermediate product to obtain the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst;

    Wherein, in step S200-a, the metal I complex includes any one of the carbonyl chloride of metal I and the acetylacetone complex of metal I;

    In step 200-b, the metal II complex is a metal II anion complex.
13. The preparation method according to claim 12, wherein the step S200-a comprises: dissolving the metal I complex in an organic solvent b at 0-200° C. under the protection of an inert atmosphere, and then dissolving the metal I complex in an organic solvent b. Adding the quaternary phosphonium salt polymer, stirring, and removing the organic solvent b, the intermediate product can be obtained.
14. The preparation method according to claim 13, wherein in step S200-a, the organic solvent b is selected from benzene, toluene, dichloromethane, tetrahydrofuran, methanol, ethanol, dimethylformamide, and chloroform one or more of them.
15. The preparation method according to claim 13, wherein in step S200-a, the mass ratio of the metal I complex to the quaternary phosphonium salt polymer is 0.01-0.05.
16. The preparation method according to claim 12, wherein step S200-b comprises: complexing the mixed solution containing metal II precursor and solvent c to obtain a solution containing metal II complex.
17. The preparation method according to claim 16, wherein the metal II precursor comprises at least one of chloride of metal II and nitrate of metal II.
18. The preparation method according to claim 16, wherein the solvent c comprises any one of concentrated hydrochloric acid and nitric acid;

    Wherein, the mass fraction of the concentrated hydrochloric acid is 36-38%.
19. The preparation method according to claim 16, wherein the ratio of the metal II precursor and the solvent c is 0.1:15-25 g/ml.
20. The preparation method according to claim 12, wherein step S200-c comprises:

    The intermediate product is immersed in the solution containing the metal II complex to obtain the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst;

    The mass ratio of the metal II complex to the intermediate product is 0.005-0.02;

    Wherein, the mass of the metal II complex is based on the mass of the metal II precursor;

    The mass of the intermediate product is based on the mass of the quaternary phosphonium salt polymer.
21. The preparation method according to claim 11, wherein the step S200 comprises:

    S200-i, obtaining a solution containing metal I complex and metal II complex;

    S200-ii, adding the quaternary phosphonium salt polymer to the solution in step S200-i, loading, to obtain the quaternary phosphonium salt polymer-supported bimetallic single-atom catalyst;

    Wherein, in step 200-i, the metal I complex is a metal I anion complex; the metal II complex is a metal II anion complex.
22. The preparation method according to claim 21, wherein the step S200-i comprises:

    The solution containing the metal I complex and the metal II complex can be obtained by mixing the metal I precursor, the metal II precursor and the solvent d, and performing a complexation reaction.
23. The preparation method according to claim 22, wherein the metal I precursor comprises at least one of metal I chloride and metal I nitrate;

    The metal II precursor includes at least one of metal II chloride and metal II nitrate.
24. The preparation method according to claim 22, wherein the solvent d comprises any one of concentrated hydrochloric acid and nitric acid;

    Wherein, the mass fraction of the concentrated hydrochloric acid is 36-38%.
25. The preparation method according to claim 22, wherein the ratio of the metal I precursor, the metal II precursor and the solvent d is 0.1-0.3 g: 0.05-0.2 g: 15-25 ml.
26. The preparation method according to claim 21, wherein in the step S200-ii, the ratio of the quaternary phosphonium salt polymer to the metal I precursor and the metal II precursor is 8-12 g: 0.1-0.3 g : 0.05～0.2g.
27. The quaternary phosphonium salt polymer-supported bimetal single-atom catalyst according to any one of claims 1 to 10 and the quaternary phosphonium salt polymer-supported bimetal single-atom catalyst obtained by the preparation method according to any one of claims 11 to 26 are in Application of methanol carbonylation to prepare methyl acetate and acetic acid.
28. A method for preparing methyl acetate and acetic acid by heterogeneous methanol carbonylation, characterized in that the method comprises: contacting and reacting raw materials containing methanol and CO with a catalyst to obtain methyl acetate and acetic acid;

    The catalyst is selected from the quaternary phosphonium salt polymer supported bimetal single-atom catalyst according to any one of claims 1 to 10 and the quaternary phosphonium salt polymer supported bimetallic catalyst obtained by the preparation method according to any one of claims 11 to 26. Any of the metal single-atom catalysts.
29. The method according to claim 28, wherein the reaction conditions are: a reaction temperature of 130-250° C.; and a reaction pressure of 0.5-3.5 MPa.
30. The method according to claim 28, wherein the reaction process further comprises a cocatalyst;

    The cocatalyst includes any one of methyl iodide and methyl bromide.
31. The method of claim 30, wherein the amount of the cocatalyst added is 1-40.0 wt% of methanol.
32. The method according to claim 28, wherein the liquid volume space velocity is 0.1～15h ⁻¹ ;

    the liquid is a methanol and cocatalyst mixture;

    The molar ratio of CO to methanol is 1-2.

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