An organic phosphine-containing polymeric support-supported palladium-based catalyst and preparation and use thereof

Abstract

The present application relates to a kind of organic phosphine-containing polymer carrier supported palladium-based catalyst and preparation and application.The organic phosphine-containing polymer is formed by one or more organic phosphine-containing monomer with vinyl through initiator initiation self-polymerization or copolymerization by solvothermal polymerization method, add palladium metal precursor solution to the obtained polymer carrier, there is strong coordination bond between metal component and phosphine ligand in the skeleton of polymer carrier or ionic bond of quaternary phosphonium salt, metal component is highly dispersed in the form of single atom in the polymer carrier, so as to prepare organic phosphine-containing polymer supported palladium-based catalyst.The obtained organic phosphine-containing polymer catalyst is a kind of heterogeneous catalyst.The catalyst is excellent in acetylene carbonylation reaction, and the selectivity of generated acrylate is good, and substrate applicability is strong.

Description

Technical Field

[0001] This invention belongs to the fields of heterogeneous catalysis and fine chemical technology, specifically relating to the application of palladium-based catalysts supported on organic phosphine polymers in the carbonylation reaction of acetylene. Background Technology

[0002] my country is a major producer and consumer of acrylates. As a raw material for organic and polymer synthesis, acrylates can be copolymerized with other monomers (such as styrene and vinyl acetate) to produce synthetic resins with various properties, functional polymer materials, and various additives. The synthesized resins are used in plastics, leather, textiles, building materials, packaging materials, coatings, and papermaking.

[0003] Acetylene, with the molecular formula C2H2, commonly known as calcium carbide gas, is an important raw material for organic synthesis and is called the "mother of organic synthesis industry." It can be easily produced by adding water to calcium carbide. my country is rich in calcium carbide and coal, enabling the abundant production of acetylene. Acetylene can be used to selectively prepare other alkynes, thereby enriching the large-scale production of alkynes and the utilization of upstream and downstream products.

[0004] Downstream fine chemicals for acetylene represent a direction for the development of acetylene and other alkyne chemicals, and can drive the in-depth development of modern acetylene-based chemical products. Using alkynes and CO as raw materials, alkyne carbonylation reactions can occur under the attack of nucleophiles.

[0005] Among them, the carbonylation of acetylene to produce acrylic acid and its esters is a typical example of industrial application. However, most of these studies are homogeneous catalysis, with the research focus mainly on the field of catalysts. [Ni(CO)4], [Co(CO)4]2, Fe(CO)5 and Pd-based catalytic systems have been developed, mainly for homogeneous catalytic reactions to prepare acrylic acid and its acrylates.

[0006] In recent years, porous organic polymers have become a new hotspot in the field of materials research due to their controllable chemical and physical properties, simple functionalization synthesis strategies, large specific area and low raw material prices. More and more porous polymers are used as supports in the field of heterogeneous catalysis.

[0007] Meanwhile, in real-world industrial production, supported metal catalysts are typically nano-sized metal catalysts, where only the atoms exposed on the surface possess catalytic activity, resulting in low metal atom utilization efficiency and waste of precious metal resources. Single-atom catalysts, with their near 100% atom utilization and single catalytic active site, have become a new research hotspot.

[0008] By impregnation, the strong coordination bond between the metal component and the P ligand in the polymer support framework, or the ionic bond of the quaternary phosphonium salt, can anchor the metal on the support, thereby preparing an atomically dispersed palladium-based catalyst supported on an organophosphorus polymer.

[0009] In summary, the existing methods for preparing acrylates by acetylene carbonylation mainly have the following problems: (1) they are basically homogeneous catalytic systems, which lead to easy catalyst loss and difficulty in product separation; (2) the reaction conditions are harsh; and (3) the catalyst dosage is large and the efficiency is low. A few supported metal catalysts are also metal nano-metal catalysts, which have low metal atom utilization. Summary of the Invention

[0010] To address the aforementioned problems, the present invention aims to provide a palladium-based catalyst supported on an organic phosphine-containing polymer support for the heterogeneous carbonylation of acetylene to acrylate, and its preparation method thereof. Due to the presence of numerous anchoring metal sites, a large specific surface area, and excellent thermal stability within the polymer support, it can meet the reaction conditions required for heterogeneous carbonylation. The process is novel and simple, with mild conditions, good reactivity, high product selectivity, strong stability, and a yield exceeding 90%, giving it a significant technological competitive advantage.

[0011] The technical solution of this invention is as follows: An organophosphorus polymer-supported palladium-based catalyst for the heterogeneous carbonylation of acetylene to acrylate and its preparation method are disclosed. The catalyst is characterized by comprising three parts: a main active component, a co-catalyst component, and a support. The active component is palladium; the co-catalyst component is one or more of ruthenium, silver, cobalt, bismuth, rhodium, copper, zinc, iron, and potassium; and the support is an organophosphorus polymer with a specific surface area of ​​100-3000 m². 2 / g, with an average pore size of 0.2-100.0nm; The main active component, palladium, has a content of 0.1-20.0% of the catalyst weight; the Pd precursor is one or more of PdCl2, PdI2, Pd(NO3)2, Pd(O2CCH3)2, and PdO; and the co-catalyst component is one or more of ruthenium, silver, cobalt, bismuth, rhodium, copper, zinc, iron, potassium chloride, oxide, and nitrate compounds.

[0012] Under an inert gas atmosphere at 273-473 K, a polymer support is added to an organic solvent containing palladium and a co-catalyst metal precursor, wherein the weight ratio of palladium content to support is 0.001:1-0.5:1; the resulting mixture is stirred for 0.1-100 hours; the resulting reaction mixture is washed with the same solvent, filtered, and then the solvent is removed under vacuum to obtain a palladium-based catalyst supported on an organophosphorus polymer support.

[0013] Acetylene, CO, alcohols, and solvents are filled into a stainless steel high-pressure reactor to carry out the acetylene carbonylation reaction, with acrylate as the main product.

[0014] The carbonylation reaction is carried out at temperatures ranging from 30 to 150°C and at pressures ranging from 0.5 to 6.5 MPa.

[0015] The partial pressures of acetylene and CO are 0.1-5.0 MPa, and the alcohols in the reactants are selected from one or more of methanol, ethanol, propanol, butanol, pentanol, and octanol; the molar ratio of acetylene to the corresponding alcohol is 1:1-1:100.

[0016] The reaction needs to be carried out in an organic solvent, which is selected from one or more of benzene, toluene, 1,4-dioxane, acetone, dimethylformamide, ethylene glycol dimethyl ether, ethanol, cyclohexane, tetrahydrofuran, and ethylene glycol methyl ether.

[0017] The palladium-based catalyst supported on an organic phosphine-containing polymer for acetylene carbonylation is used in the reaction of converting acetylene, CO, and alcohols into acrylates.

[0018] The organophosphorus polymer is preferably prepared by the following method: First, under a protective atmosphere of 273-473 K and an inert gas such as nitrogen or argon, in a three-necked round-bottom flask equipped with a stirrer and temperature control device, a free radical initiator is added to an organic solvent containing p- and alkenyl-functionalized organic ligand monomers, such as triphenylphosphine ligands containing vinyl-functionalized ligands, wherein the weight ratio of the phosphine-containing monomer to the free radical initiator is 0.5:1-100:1; and the resulting mixture is stirred for 0.1-100 hours; preferably, the organic solvent used can be one or a mixture of several of toluene, dichloromethane, tetrahydrofuran, or dimethylformamide; the free radical initiator can be one of azobisisobutyronitrile or azobisisoheptanenitrile. Subsequently, the mixture is transferred to a closed reactor, such as a hydrothermal reactor, and under a protective atmosphere of 293-473 K and an inert gas such as nitrogen or argon, the solution is allowed to stand for 1-100 hours to allow the organic phosphine-containing monomer to polymerize, thereby generating the desired high-surface-area polymer carrier with a multipolar porous structure. Finally, the solvent was removed from the polymerized reaction mixture under vacuum to obtain a high-surface-area organophosphorus polymer support with a multipolar porous structure. The specific surface area and pore size distribution of the samples were determined using an Autosorb-1 adsorption analyzer from Quantachrome Instruments. Prior to testing, the samples were pretreated at 373 K for 20 hours.

[0019] The beneficial effects of this invention are as follows: Compared with existing acetylene carbonylation techniques for preparing acrylates, the palladium-based catalyst supported on the organophosphorus polymer support of this invention exhibits milder reaction conditions and higher reactivity in the heterogeneous carbonylation reaction of acetylene.

[0020] This organophosphorus polymer support is generated through solvothermal polymerization using organic ligands or salts containing multiple phosphine vinyl groups, via self-polymerization or copolymerization followed by initiation with an initiator. This large-surface-area, hierarchical porous organophosphorus polymer can serve as a support for supported metal catalysts, loading active metal components. Furthermore, due to the strong coordination bonds between the metal components and the phosphine ligands in the polymer support framework, or the ionic bonds of the quaternary phosphonium salt, the palladium metal component is highly dispersed in the polymer support in a single-atom form. In a high-pressure reactor, under specific temperature and pressure conditions and with the aid of this catalyst, acetylene / CO / alcohol can be converted to acrylates with high activity and selectivity.

[0021] The beneficial effects of this patent application include, but are not limited to: Compared with existing technologies, this invention provides a palladium-based single-atom catalyst supported on an organophosphorus polymer and its application in the carbonylation of acetylene to prepare acrylate. The catalyst used in this technology is a supported palladium-based catalyst with a single metal active site, belonging to the category of single-atom catalysis. When applied to the acetylene carbonylation reaction, this catalyst offers a novel and simple process, mild conditions, good reactivity, and high product selectivity. The reaction does not require the addition of corrosive solvents such as sulfuric acid or hydrochloric acid, nor does it require the addition of co-catalysts such as sulfonic acid, benzenesulfonic acid, or p-toluenesulfonic acid, thus avoiding equipment corrosion. This innovative approach gives it a significant technological competitive advantage.

[0022] The organophosphorus polymer is synthesized by solvothermal polymerization of one or more organophosphorus monomers containing vinyl groups via initiation or copolymerization. A palladium metal precursor solution is added to the resulting polymer support. The strong coordination bonds between the metal component and the phosphorus ligands in the polymer support backbone, or the ionic bonds of the quaternary phosphonium salt, highly disperse the metal component in the polymer support in a single-atom form, thereby preparing a palladium-based catalyst supported on an organophosphorus polymer. The resulting organophosphorus polymer catalyst is a heterogeneous catalyst.

[0023] Palladium catalysts with single-metal active sites exhibit excellent performance in the carbonylation of acetylene to prepare acrylates, demonstrating good selectivity in acrylate formation and strong substrate applicability. Attached Figure Description

[0024] Figure 1 This is a transmission electron microscope (TEM) image of the sample from Example 1.

[0025] Figure 2 This is a spherical aberration electron microscope image of the sample from Example 1.

[0026] Depend on Figure 1 As can be seen from Example 1, the metal components in the sample are highly dispersed in the polymer carrier in the form of single atoms. Detailed Implementation

[0027] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0028] Unless otherwise specified, all raw materials and reagents used in this application are commercially purchased and used directly without processing. The instruments and equipment used adopt the manufacturer's recommended scheme and parameters.

[0029] In this embodiment, the transmission electron microscope was used with a JEM-2100 instrument from Japan.

[0030] In this embodiment, the spherical aberration electron microscope was used with a JEM-ARM200F instrument from Japan.

[0031] In the examples, the specific surface area, pore volume, and pore size distribution of the samples were determined using an Autosorb-1 physicochemical adsorption instrument from Quantachrome Instruments.

[0032] In the examples, all catalyst evaluation results were analyzed using an Agilent 7890B liquid chromatograph, an FID detector, a capillary column, and an internal standard method to determine the liquid phase composition, with methyl benzoate as the internal standard. Product selectivity is calculated based on the composition of each product.

[0033] In the embodiments of this application, the conversion rate of acetylene and the selectivity of the product are calculated based on the number of moles of acetylene that have been converted.

[0034] Example 1 Under an argon atmosphere at 298 K, 5.0 g of methyltristyrylphosphonium iodide was dissolved in 50 ml of dimethylformamide. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After stirring for 0.5 h, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After cooling the polymerized solution to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​580 m²) polymerized from methyltristyrylphosphonium iodide. 2 / g, pore volume 0.65cm 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0035] Then, under a protective atmosphere of argon at 298 K, 0.17 g of PdCl2 and 0.19 g of RuCl3 were dissolved in a mixed solution of 10 ml of 36% hydrochloric acid and 290 ml of deionized water, and then 10 g of the above polymer support was added. After stirring for 24 h under a protective atmosphere of argon at 298 K, the mixture was washed with deionized water, and the solvent was removed by filtration to obtain an atomically dispersed Pd-Ru catalyst supported on an organophosphorus polymer with a mass loading of 1% (which refers to the mass ratio of Pd to the organophosphorus polymer; the meaning of Pd mass loading is the same in the following examples).

[0036] Example 2 Under an argon atmosphere at 298 K, 5.0 g of methyltristyrylphosphonium bromide was dissolved in 50 ml of toluene. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After stirring for 0.5 h, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After cooling the polymerized solution to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​560 m²) polymerized from methyltristyrylphosphonium bromide. 2 / g, pore volume 0.6cm 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0037] Then, under an argon protective atmosphere at 298 K, 0.17 g of PdCl2 and 0.31 g of FeCl3 were dissolved in a mixed solution of 10 ml of 36% hydrochloric acid and 290 ml of deionized water, and then 10 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with deionized water, and the solvent was removed by filtration to obtain an atomically dispersed Pd-Fe catalyst (molar ratio 1:2) supported on an organophosphorus polymer with a Pd mass loading of 1%.

[0038] Example 3 Under an argon atmosphere and at 298 K, 5.0 g of ethyl-tristyrylphosphonium iodide was dissolved in 100 ml of dichloromethane. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After thorough stirring, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After the polymerized solution cooled to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​600 m²) polymerized from ethyl-tristyrylphosphonium iodide. 2 / g, pore volume is 0.68cm³ 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0039] Then, under an argon protective atmosphere at 298 K, 0.17 g of PdI₂ and 0.35 g of KCl were dissolved in a mixed solution of 10 ml of 36% hydrochloric acid and 290 ml of methanol, and then 10 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with methanol, and the solvent was removed by filtration to obtain an atomically dispersed Pd-K (molar ratio 1:5) catalyst supported on an organophosphorus polymer with a Pd mass loading of 1%.

[0040] Example 4 Under an argon atmosphere at 298 K, 5.0 g of trivinylphosphine and 5.0 g of methyl-tristyrylphosphine iodide were dissolved in 100 ml of dimethylformamide. 0.5 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After thorough stirring, the mixture was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After cooling the polymerized solution to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer carrier copolymerized from trivinylphosphine and methyl-tristyrylphosphine iodide (BET specific surface area of ​​550-700 m²). 2 / g, pore volume 570 cm³ 3 / g, pore volume 0.62cm 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0041] Then, under an argon protective atmosphere at 298 K, 0.15 g of Pd(NO3)2 and 0.19 g of AgNO3 were dissolved in 300 ml of deionized water, and then 6 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with deionized water, and the solvent was removed by filtration to obtain a Pd-Ag catalyst supported on an organophosphorus polymer with a Pd mass loading of 1% (molar ratio of 1:2).

[0042] Example 5 Under an argon atmosphere and at 298 K, 5.0 g of methyltristyrylphosphonium iodide was dissolved in 50 ml of dimethylformamide. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After thorough stirring, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After cooling the polymerized solution to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​750 m²) polymerized from methyltristyrylphosphonium iodide. 2 / g, pore volume 0.5cm 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0043] Then, under an argon protective atmosphere at 298 K, 0.51 g of PdI₂ and 2.67 g of BiCl₃ were dissolved in a mixed solution of 10 ml of 36% hydrochloric acid and 290 ml of ethanol, and then 10 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with ethanol, and the solvent was removed by filtration to obtain an atomically dispersed Pd-Bi (molar ratio 1:3) catalyst supported on an organophosphorus polymer with a Pd mass loading of 3%.

[0044] Example 6 Under an argon atmosphere and at 298 K, 5.0 g of methyltristyrylphosphonium iodide was dissolved in 50 ml of dimethylformamide. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After thorough stirring, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After cooling the polymerized solution to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​535 m²) polymerized from methyltristyrylphosphonium iodide. 2 / g, pore volume is 0.58cm 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0045] Then, under an argon protective atmosphere at 298 K, 0.17 g PdCl2 and 0.13 g CuCl2 were dissolved in a mixed solution of 10 ml of 36% hydrochloric acid and 290 ml of dichloromethane, and then 10 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with dichloromethane, and the solvent was removed by filtration to obtain an atomically dispersed Pd-Bi (molar ratio 1:1) catalyst supported on an organophosphorus polymer with a Pd mass loading of 1%.

[0046] Example 7 Under an argon atmosphere and at 298 K, 5.0 g of methyltristyrylphosphonium iodide was dissolved in 50 ml of dimethylformamide. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator. After thorough stirring, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After the polymerized solution cooled to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​600 m²) polymerized from methyltristyrylphosphonium iodide. 2 / g, pore volume is 0.52 cm³ 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0047] Then, under an argon protective atmosphere at 298 K, 0.17 g of PdCl2 and 0.19 g of RhCl3 were dissolved in a mixed solution of 10 ml of 36% hydrochloric acid and 290 ml of deionized water, and then 10 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with deionized water, and the solvent was removed by filtration to obtain an atomically dispersed Pd-Cu (molar ratio 1:1) catalyst supported on an organophosphorus polymer with a Pd mass loading of 1%.

[0048] Example 8 Under an argon atmosphere and at 298 K, 5.0 g of tristyrylphosphine was dissolved in 100 ml of tetrahydrofuran solvent. 0.25 g of azobisisobutyronitrile (AIBN) was added as a free radical initiator to the solution. After thorough stirring, the mixture was transferred to a hydrothermal reactor and polymerized at 373 K under an argon atmosphere using a solvothermal polymerization method for 24 h. After the polymerized solution cooled to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer support (BET specific surface area of ​​670 m²) polymerized from tris(4-vinylphenyl)phosphine. 2 / g, pore volume 0.6cm 3 / g, pore size distribution in the range of 0.5-100.0nm).

[0049] Then, under an argon protective atmosphere at 298 K, 0.21 g of Pd(O2CCH3)2 was dissolved in a mixed solution of 300 ml of concentrated hydrochloric acid (36% by mass) and 290 ml of deionized water, and then 10 g of the above polymer support was added. After stirring for 24 h under an argon protective atmosphere at 298 K, the mixture was washed with deionized water, and the solvent was removed by filtration to obtain an atomically dispersed Pd catalyst supported on an organophosphorus polymer with a mass loading of 1%.

[0050] Example 9 (Comparative Example) Under an argon protective atmosphere at 298 K, 5.0 g of trivinylphosphine was dissolved in 50 ml of tetrahydrofuran solvent. 0.25 g of azobisisobutyronitrile (AIBN) was added to the solution as a free radical initiator. After thorough stirring, the solution was transferred to a hydrothermal reactor and polymerized at 373 K under an argon protective atmosphere using a solvothermal polymerization method for 24 h. After the polymerized solution cooled to room temperature, the solvent was removed under vacuum to obtain an organophosphorus polymer carrier polymerized from trivinylphosphine.

[0051] Then, under a protective atmosphere of argon at 298 K, a mixed solution of 0.15 g PdO dissolved in 300 ml of deionized water was added, followed by the addition of 10 g of the aforementioned polymer support (BET specific surface area of ​​580 m²). 2 / g, pore volume is 0.53cm 3 / g (pore size distribution in the range of 0.5-100.0 nm). After stirring for 24 h at 298 K under an argon protective atmosphere, the catalyst was washed with deionized water and filtered to remove the solvent, yielding an atomically dispersed Pd catalyst supported on an organophosphorus polymer with a mass loading of 1%.

[0052] Example 10 (Comparative Example) Measure 0.17g of PdCl2 and dissolve it in 15ml of deionized water. Then add 10g of activated carbon support, impregnate and stir until no bubbles are generated, evaporate the solvent in a 90℃ water bath, dry in an oven at 120℃ for 8h, and calcine under nitrogen protection at 300℃ for 4h to obtain activated carbon-supported Pd / AC nanoparticles. Then treat them with a mixture of CO and CH3I gas (molar ratio 1:1) at 100℃ for 0.5h to obtain atomically dispersed activated carbon-supported Pd catalyst.

[0053] Application Example 1 Using acetylene as the reaction substrate, the carbonylation reaction performance of the catalysts obtained in Examples 1-11 was tested.

[0054] 150 mg of the catalyst obtained in Examples 1-11 were weighed and placed in a 50 mL batch reactor (the main reactor was a stainless steel high-pressure reactor) along with 2.5 g of ethanol and 12.5 g of 1,4-dioxane. A mixture of CO and acetylene was introduced. The pressure was: C2H2: 0.4 MPa, CO: 2.6 MPa, and the molar ratio of acetylene to ethanol was 1:6. The reaction was carried out at 60 °C and 600 rpm for 8 hours. The conversion rate of acetylene and the selectivity of each product were analyzed and calculated. The results are detailed in Table 1.

[0055] Table 1. Results of catalysts used in Examples 1-6 for the synthesis of methyl esters via acetylene carbonylation.

[0056] The results showed that the Pd-based single-atom catalyst supported on the support obtained after polymerization of halogenated organophosphorus monomers (such as methyl-tristyrylphosphonium iodide and methyl-trivinylphosphonium bromide) was more conducive to the reaction. The presence of Ru, Ag, or Rh as the co-active component further facilitated the acetylene carbonylation reaction.

[0057] Application Example 2 150 mg of the catalyst obtained in Example 1, 3 g of different alcohols (in excess) (see Table 2 below), and 15 g of 1,4-dioxane were weighed and placed in a 50 mL batch reactor. A mixture of CO and acetylene was introduced, with C2H2: 0.4 MPa and CO: 2.6 MPa, and the molar ratio of acetylene to alcohol was 1:7. The reaction was carried out at 60 °C and 600 rpm for 8 h. The conversion rate of acetylene and the selectivity of each product were analyzed and calculated. The results are detailed in Table 2.

[0058] Table 2. Results of catalysts used in Example 1 for the synthesis of various esters via acetylene carbonylation.

[0059] Note: When the substrate is methanol, the products are methyl acrylate, dimethyl succinate, and dimethyl butenedioate; when the substrate is ethanol, the products are ethyl acrylate, diethyl succinate, and diethyl butenedioate; when the substrate is propanol, the products are propyl acrylate, dipropyl succinate, and dipropyl butenedioate; when the substrate is butanol, the products are butyl acrylate, dibutyl succinate, and dibutyl butenedioate; when the substrate is pentanol, the products are pentyl acrylate, dipentyl succinate, and dipentyl butenedioate; when the substrate is octanol, the products are octyl acrylate, dioctyl succinate, and dioctyl butenedioate.

[0060] The results show that the Pd-based catalyst supported on the organophosphorus polymer is applicable to the carbonylation of acetylene to prepare acrylates, exhibiting good versatility. Furthermore, it demonstrates excellent catalytic activity and selectivity for acrylates.

[0061] Application Example 3 150 mg of the catalyst obtained in Example 1 was weighed and placed in a 50 mL batch reactor along with 2.5 g of ethanol (excess) and 12.5 g of different solvents. A mixture of CO and acetylene was introduced, with C2H2: 0.4 MPa and CO: 3.6 MPa, and the molar ratio of acetylene to ethanol was 1:6. The reaction was carried out at 60 °C and 600 rpm for 8 h. The conversion rate of acetylene and the selectivity of each product were analyzed and calculated. The results are detailed in Table 2.

[0062] Table 3 Results of the catalyst in Example 1 for the synthesis of acrylate by acetylene carbonylation

[0063] The results show that the reaction has a solvent effect. When using solvents with low polarity (such as cyclohexane, benzene, acetone, etc.), the acetylene carbonylation reaction can be promoted; when using solvents with high polarity (such as DMF, methylpyrrolidone or water), the reaction will be inhibited.

[0064] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. The application of palladium-based catalysts supported on organic phosphine polymer supports in the carbonylation of acetylene to prepare acrylates, characterized in that: The palladium-based catalyst comprises or consists of three parts: a main active component, a co-active component, and a support. The main active ingredient is palladium; the auxiliary active ingredients are one or more of ruthenium, silver, bismuth, zinc, and potassium; the carrier is an organic phosphine-containing polymer. The weight ratio of palladium metal to support is 0.001:1-0.05:1; the weight ratio of co-active ingredient metal to support is 0.0001:1-0.3:

1. The reaction temperature is 60℃, the partial pressure of acetylene is 0.01~1MPa; the partial pressure of CO is 0.05-6 MPa; the pressure ratio of acetylene to CO is 1:1~1:10; the alcohol in the reactants is selected from one or more of methanol, ethanol, propanol, butanol, pentanol and octanol; the molar ratio of acetylene to the corresponding alcohol is 1:2-1:100; The method for preparing the organophosphorus polymer carrier includes, a) Under one or two protective atmospheres of nitrogen or argon at 273-473 K, a free radical initiator is added to an organic solvent containing an organophosphorus monomer, wherein the weight ratio of the phosphorus monomer to the free radical initiator is 0.5:1-100:1; and the resulting mixture solution is stirred evenly. b) Under one or two protective atmospheres of nitrogen or argon at 273-473 K, the mixture solution from step a) is transferred to a hydrothermal reactor and allowed to stand for 1-100 h under solvothermal polymerization conditions at 333 K-423 K to carry out the polymerization reaction. c) The polymerization reaction mixture obtained in step b) is desolventized at 273K-473K to obtain an organophosphorus polymer support; The organophosphorus monomer is one or more of triphenylphosphine, triethylenephosphine, methyl-triphenylphosphine iodide, and methyl-trivinylphosphine bromide.

2. The application according to claim 1, characterized in that: The weight ratio of palladium metal to support is 0.005:1-0.03:1; the weight ratio of co-active ingredient metal to support is 0.005:1-0.1:

1. The partial pressure of acetylene is 0.1~0.5 MPa; the partial pressure of CO is 0.2~5 MPa; the pressure ratio of acetylene to CO is 1:2~1:5; the alcohol in the reactants is selected from one or more of methanol, ethanol, propanol, butanol, pentanol and octanol; the molar ratio of acetylene to the corresponding alcohol is 1:2-1:10; The method for preparing the organophosphorus polymer carrier includes, a) Under one or two protective atmospheres of nitrogen or argon at 273-473 K, add a free radical initiator to an organic solvent containing an organophosphorus monomer, wherein the weight ratio of the phosphorus monomer to the free radical initiator is 2:1-50:1; and stir the resulting mixture solution until homogeneous. b) Under one or two protective atmospheres of nitrogen or argon at 273-473 K, the mixture solution from step a) is transferred to a hydrothermal reactor and allowed to stand for 12-48 h under solvothermal polymerization conditions at 333 K-423 K to carry out the polymerization reaction. c) The polymerization reaction mixture obtained in step b) is desolventized at 273K-473K to obtain an organophosphorus polymer support.

3. The application according to claim 1, characterized in that: The specific surface area of ​​the organophosphorus polymer carrier is 100-3000 m². 2 / g, pore volume 0.1-5.0 cm³ 3 / g, with a pore size distribution of 0.2-100.0 nm.

4. The application according to claim 1, characterized in that: The organic solvent used in step a) is selected from one or more of the following: acetone, dichloromethane, chloroform, dimethylformamide, acetonitrile, diethyl ether, tetrahydrofuran, methanol, ethanol, benzene, and toluene. The free radical initiator is selected from one or more of cyclohexanone peroxide, benzoyl peroxide, tert-butyl hydroperoxide, azobisisobutyronitrile, or azobisisoheptanenitrile. The molar ratio of the organophosphorus monomer to the free radical initiator in step a) is 0.5:1-100:1; the concentration of the organophosphorus monomer in the solvent is 0.01-1000 g / L.

5. The application according to claim 4, characterized in that: The molar ratio of the organophosphorus monomer to the free radical initiator in step a) is 2:1-50:1; the concentration of the organophosphorus monomer in the solvent is 1-500 g / L.

6. The application according to claim 1, characterized in that: The method for preparing the palladium-based catalyst supported on the organophosphorus polymer support includes: a) Under one or two protective atmospheres, namely nitrogen or argon, at 273–473 K, an organic phosphine-containing polymer support is added to a precursor solution containing palladium and a co-active metal, wherein the weight ratio of palladium metal to support is 0.001:1–0.05:1; and the resulting mixture solution is stirred for 0.1–100 h. b) The reaction mixture obtained in step a) was washed and filtered at room temperature with the same solvent used for the precursor solution to remove the solvent, thereby obtaining a palladium-based catalyst supported on an organophosphorus polymer support.

7. The application according to claim 6, characterized in that: The method for preparing the palladium-based catalyst supported on the organophosphorus polymer support includes: a) Under one or two protective atmospheres of 273–473 K and inert gases nitrogen and argon, an organic phosphine-containing polymer support is added to a precursor solution containing palladium and a co-active metal, wherein the weight ratio of palladium metal to support is 0.005:1–0.03:1; and the resulting mixture solution is stirred for 12–48 h. b) The reaction mixture obtained in step a) was washed and filtered at room temperature with the same solvent used for the precursor solution to remove the solvent, thereby obtaining a palladium-based catalyst supported on an organophosphorus polymer support.

8. The application according to claim 6, characterized in that: The solvent used in step a) is selected from one or more of water, benzene, toluene, dichloromethane, tetrahydrofuran, methanol, ethanol, dimethylformamide, and chloroform. If the metal precursor is insoluble in water, hydrochloric acid is added for dissolution. The concentration of hydrochloric acid in the precursor solution is 0.001-10 g / L; the concentration of palladium in the precursor solution is 0.01-1000 g / L. The precursors of palladium and the co-active metal are each independently selected from one or more of the following: metal chlorides, oxides, nitrate compounds, phosphate compounds, oxides, and carbonyl compounds. The palladium precursor is one or more palladium compounds; The active ingredient is one or more of ruthenium, silver, bismuth, zinc, and potassium, and its precursor is one or more of metal compounds.

9. The application according to claim 8, characterized in that: The concentration of palladium in the precursor solution is 0.25-500 g / L; The palladium precursor is one or more of palladium chloride, palladium nitrate, palladium acetate, and palladium iodide. The active ingredient is one or two of ruthenium chloride and oxide.

10. The application according to claim 1, characterized in that: The main reactor used in the acetylene carbonylation reaction to prepare acrylate is a stainless steel high-pressure reactor; the reaction pressure is 0.5-6.5 MPa.

11. The application according to claim 1, characterized in that: The acetylene carbonylation reaction to prepare acrylate needs to be carried out in an organic solvent, which is selected from one or more of benzene, toluene, 1,4-dioxane, acetone, dimethylformamide, ethylene glycol dimethyl ether, ethanol, cyclohexane, tetrahydrofuran, and ethylene glycol methyl ether; the reaction time is 0.5-50 h.

12. The application according to claim 11, characterized in that: The reaction time is 1-24 h.

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