Catalyst for liquid-phase oxidative carbonylation of methanol to dimethyl carbonate, preparation method and application thereof

Abstract

The present invention relates to a catalyst for methanol liquid phase oxidative carbonylation to synthesize dimethyl carbonate, and its preparation method and application. The catalyst is a MOFs derivative, and the metal oxide is dispersed on a carbon carrier. The metal oxide is CuO X The MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon support, the MOF derivative is used in an amount of 1.3% to 3.8% of the amount of methanol used. Compared to existing technologies, this invention leverages the advantages of MOFs, such as adjustable metal nodes and ligand structures, large specific surface area, and diverse structures. The resulting derivatives after calcination also have the advantages of high specific surface area and highly dispersed metal oxides on the carbon support.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a catalyst for synthesizing dimethyl carbonate by liquid-phase oxidative carbonylation of methanol, and a preparation method and application thereof. Background Art

[0002] Dimethyl carbonate, registered as a non-toxic chemical in Europe in 1992, is known as the "cornerstone" of green synthetic chemistry and is widely used in pesticides, medicines, plastics, dyes, electronic chemicals, food additives and other fields; it can also be used as an electrolyte solvent, which is one of the core materials of lithium batteries.

[0003] Currently, the industrial production of dimethyl carbonate primarily relies on the transesterification process, using ethylene carbonate and methanol as raw materials. This is a typical petrochemical route, significantly affected by oil prices. Furthermore, the byproduct, ethylene glycol, is produced, and its sales volume constrains plant operating rates to a certain extent. The direct one-step synthesis of dimethyl carbonate from CO2 and methanol has also attracted considerable research interest, but methanol conversion rates remain low. In recent years, the processes for synthesizing dimethyl carbonate by liquid-phase oxidative carbonylation of methanol and alcoholysis of urea have matured, with reports of pilot or industrial plant startups. However, most of the reported catalysts contain halogens, resulting in low activity and reaction efficiency. Furthermore, halogen ions are highly corrosive to stainless steel reactors.

[0004] Patent application CN201610647640.0 discloses a catalyst and method for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate. The catalyst comprises a copper halide and an ionic liquid; the mass ratio of the copper halide to the ionic liquid is 1:(1-10); the cation of the ionic liquid is an imidazolium, quaternary ammonium, or pyridinium type, and the anion is a halide ion. The catalyst has a high selectivity for dimethyl carbonate, reaching up to 99.8%. Furthermore, the addition of the ionic liquid mitigates corrosion of stainless steel reaction equipment. However, this technology does not fundamentally address the corrosion caused by halide ions on stainless steel equipment, making the development of halogen-free catalysts particularly important.

[0005] Patent application CN201310077972.6 discloses a catalyst for the continuous oxidative carbonylation of methanol in the liquid phase to produce dimethyl carbonate. The catalyst comprises Cu2O and activated carbon (Cu2O / AC), with the active components being 5.0-25.0 wt% Cu2O and 75.0-95.0 wt% activated carbon. This catalyst exhibits excellent activity and stability in the continuous liquid-phase oxidative carbonylation of methanol to produce DMC, with a selectivity exceeding 95%. However, the catalyst dosage is relatively high, at 6.5-22.6% of the methanol mass, and the space-time yield of DMC is only 300-700 mg / g. -1 ·h -1. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a catalyst for the liquid phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, a preparation method and application thereof, which is free of halogen, CuO X Advantages of being highly dispersed on carbon supports.

[0007] The purpose of the present invention can be achieved by the following technical solution: a catalyst for the liquid phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, the catalyst is a MOFs (metal organic framework) derivative, the metal oxide is dispersed on a carbon support, the metal oxide is CuO X .

[0008] Furthermore, the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon support.

[0009] Furthermore, the catalyst has a topological structure and a specific surface area of ​​10 to 150 m 2 ·g -1 The surface of the catalyst is distributed with mesopores with a pore size of 4 to 35 nm.

[0010] The present invention also provides a method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate, comprising the following steps:

[0011] S101, dissolving copper salt in deionized water to obtain solution A;

[0012] S102, dissolving H3BTC and PVP in a mixture of deionized water, ethanol, and DMF to obtain solution B;

[0013] S103, adding solution B to solution A, stirring, and mixing thoroughly to obtain suspension C;

[0014] S104, transferring the suspension C to a hydrothermal reactor and reacting at 100-150° C. for 12-36 hours to obtain a solution D having a blue precipitate;

[0015] S105, centrifuging solution D and washing until the supernatant is colorless;

[0016] S106, drying the washed product to obtain a blue powdery Cu-MOF;

[0017] S107. Carbonize the Cu-MOF at high temperature under a N2 atmosphere to obtain a catalyst MOFs derivative.

[0018] The copper salt includes Cu(NO3)2·3H2O.

[0019] In step S102 , the volume ratio of deionized water, ethanol, and DMF is 1:1:0-1.

[0020] In step S102, the mass ratio of H3BTC to PVP is 1:0-1.1.

[0021] The molar ratio of copper salt to H3BTC in suspension C is 1.5 to 2:1.

[0022] In step S107 , the carbonization temperature is 300-500° C., the heating rate is 3-6° C. / min, and the carbonization time is 1-3 hours.

[0023] The catalyst is used for liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, and the amount of the catalyst used is 1.3%-3.8% of the mass of the methanol.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The catalyst of the present invention is a metal organic framework (MOFs) derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Highly dispersed on a carbon support, MOFs are a novel porous inorganic-organic material composed of metal ions or metal clusters and organic linking ligands. They possess characteristics such as adjustable metal junction and ligand structures, large specific surface area, and diverse structures. Because the organic ligands in MOFs readily decompose at high temperatures, MOF derivatives produced by high-temperature carbonization possess advantages such as large specific surface area, highly dispersed metal centers, adjustable porosity, and ease of modification.

[0026] This invention designs a catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate. The catalyst, derived after calcination, inherits the periodically arranged framework of MOFs. The metal oxides are highly dispersed on a carbon support. MOFs offer adjustable metal nodes and ligand structures, along with structural diversity, making the derived catalyst highly controllable. This catalyst avoids corrosion of stainless steel equipment, exhibits good dimethyl carbonate selectivity, and produces virtually no byproducts.

[0027] (2) The present invention selects H3BTC and PVP as raw materials, dissolves them in a mixture of ionized water, ethanol and DMF, wherein DMF can promote the formation of Cu-MOF crystals, and PVP can protect the structure of Cu-MOF from being destroyed by water in the air and promote the formation of a porous carbon shell during the carbonization process. Then, the raw materials are mixed with a solution containing copper ions, and a hydrothermal reaction is performed to synthesize Cu-MOF with high crystal phase purity. Under the carbonization conditions of the present invention, the periodic arrangement skeleton structure of MOFs can be maintained to the maximum extent, and the aggregation of Cu nanoparticles can be suppressed. The obtained catalyst shows good activity and stability in the reaction of methanol liquid-phase oxidative carbonylation to synthesize dimethyl carbonate, with a methanol conversion rate of 1.7-2.4%, a selectivity of 100%, and a maximum space-time yield of DMC of 1295 mg·g -1 ·h -1 . BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the SEM image of Cu-BTC-PVP-1 of the present invention;

[0029] Figure 2 CuO X / SEM image of PC-1;

[0030] Figure 3 Cu-BTC-PVP-1 and CuO X / XRD pattern of PC-1;

[0031] Figure 4 Cu-BTC-PVP-1 and CuO X N2 adsorption / desorption and pore size distribution spectra of / PC-1. DETAILED DESCRIPTION

[0032] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1:

[0034] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0035] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0036] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0037] S102, dissolving 2.5 g of H3BTC and 2.7 g of PVP in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0038] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0039] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0040] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0041] S106, drying the washed product in an oven at 120°C overnight to obtain blue powdered Cu-BTC-PVP-1;

[0042] S107. Place Cu-BTC-PVP-1 in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / PC-1.

[0043] The SEM image of the uncarbonized Cu-BTC-PVP-1 is as follows: Figure 1 As shown, it presents a typical octahedral structure with a particle size of 2 microns; the derived CuO X / SEM image of PC-1, such as Figure 2 As shown in Figure 2, the surface of the regular octahedron shrinks slightly inward, the particle size decreases, but the basic skeleton structure is retained, and a large number of spherical CuO appear on the surface and in the graphitized carbon shell. X particles.

[0044] Cu-BTC-PVP-1 and CuO X / PC-1 XRD pattern, such as Figure 3 As shown, the XRD spectrum of Cu-BTC-PVP-1 is similar to that of CuO X / PC-1 simulation spectrum is highly consistent, indicating that the addition of PVP to Cu-BTC does not affect its crystal form. After carbonization, the diffraction peak of Cu-BTC-PVP-1 disappears, and characteristic diffraction peaks attributed to Cu appear at 40.3°, 50.5°, and 70.1°, and a weak characteristic diffraction peak attributed to Cu2O appears at 36.4°. This shows that during the carbonization process, Cu 2+ Reduced to Cu and Cu2O.

[0045] Cu-BTC-PVP-1 and CuO XN2 adsorption / desorption and pore size distribution spectrum of PC-1, such as Figure 4 As shown, CuO X / The specific surface area of ​​PC-1 is 102m 2 ·g -1 Lower than the specific surface area of ​​Cu-BTC-PVP-1 before carbonization (883m 2 ·g -1 ), which is caused by the structural collapse of Cu-BTC-PVP-1 after high temperature carbonization. Cu-BTC-PVP-1 and its derived CuO X / PC-1 showed a type IV adsorption isotherm and an H4 hysteresis loop, indicating that both were mesoporous structures, but the pore size of Cu-BTC-PVP-1 was concentrated at 4 nm. X Some mesopores with a size of 4-18 nm were also observed in Cu-BTC-PVP-1, indicating that the high-temperature carbonization process broadened the pore size distribution of Cu-BTC-PVP-1, which is beneficial to the transport of substances.

[0046] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 1188 mg·g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0047] Example 2:

[0048] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 2.5% of the mass of methanol.

[0049] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0050] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0051] S102, dissolving 2.5 g of H3BTC and 2.7 g of PVP in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0052] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0053] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0054] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0055] S106, drying the washed product in an oven at 120°C overnight to obtain blue powdered Cu-BTC-PVP-1;

[0056] S107. Place Cu-BTC-PVP-1 in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / PC-1.

[0057] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.2 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 605 mg g. -1 ·h -1 , methanol conversion rate is 2.19%, and dimethyl carbonate selectivity is 100%.

[0058] Example 3:

[0059] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 3.8% of the mass of methanol.

[0060] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0061] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0062] S102, dissolving 2.5 g of H3BTC and 2.7 g of PVP in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0063] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0064] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0065] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0066] S106, drying the washed product in an oven at 120°C overnight to obtain blue powdered Cu-BTC-PVP-1;

[0067] S107. Place Cu-BTC-PVP-1 in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / PC-1.

[0068] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.3 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 413 mg·g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0069] Example 4:

[0070] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0071] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0072] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0073] S102, dissolving 2.5 g of H3BTC and 1.4 g of PVP in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0074] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0075] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0076] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0077] S106, drying the washed product in an oven at 120° C. overnight to obtain blue powdered Cu-BTC-PVP-2;

[0078] S107. Place Cu-BTC-PVP-2 in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / PC-2.

[0079] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 1254 mg g⁻¹. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0080] Example 5:

[0081] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0082] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0083] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0084] S102, dissolving 2.5 g of H3BTC and 0.7 g of PVP in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0085] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0086] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0087] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0088] S106, drying the washed product in an oven at 120° C. overnight to obtain blue powdered Cu-BTC-PVP-3;

[0089] S107. Place Cu-BTC-PVP-3 in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / PC-3.

[0090] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 1295 mg g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0091] Example 6:

[0092] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0093] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0094] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0095] S102, dissolving 2.5 g of H3BTC and 0.3 g of PVP in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0096] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0097] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0098] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0099] S106, drying the washed product in an oven at 120° C. overnight to obtain blue powdered Cu-BTC-PVP-4;

[0100] S107. Place Cu-BTC-PVP-4 in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / PC-4.

[0101] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 1029 mg·g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0102] Example 7:

[0103] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0104] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0105] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0106] S102, dissolving 2.5 g of H3BTC in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0107] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0108] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0109] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0110] S106, drying the washed product in an oven at 120° C. overnight to obtain blue powdered Cu-BTC;

[0111] S107. Place Cu-BTC in a tube furnace and carbonize at 400°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / C-400.

[0112] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 948 mg g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0113] Example 8:

[0114] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0115] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0116] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0117] S102, dissolving 2.5 g of H3BTC in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0118] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0119] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0120] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0121] S106, drying the washed product in an oven at 120° C. overnight to obtain blue powdered Cu-BTC;

[0122] S107. Place Cu-BTC in a tube furnace and carbonize at 300°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / C-300.

[0123] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 1166 mg g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0124] Example 9:

[0125] A catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, wherein the catalyst is a MOFs derivative, and the MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on a carbon carrier, the catalyst is used in an amount of 1.3% of the mass of methanol.

[0126] The method for preparing the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate comprises the following steps:

[0127] S101, dissolve 4.0 g of Cu(NO3)2·3H2O in 15 mL of deionized water to obtain solution A;

[0128] S102, dissolving 2.5 g of H3BTC in 125 mL of a mixture of deionized water, ethanol, and DMF to obtain solution B, wherein the volume ratio of deionized water, ethanol, and DMF is 1:1:1;

[0129] S103, adding solution B to solution A, stirring for 10 minutes, and mixing thoroughly to obtain suspension C;

[0130] S104, transfer suspension C to a 200 mL hydrothermal kettle, place in a 120°C oven and react for 24 h to obtain solution D with a blue precipitate;

[0131] S105, centrifuging solution D and washing with deionized water and ethanol multiple times until the supernatant is colorless;

[0132] S106, drying the washed product in an oven at 120° C. overnight to obtain blue powdered Cu-BTC;

[0133] S107. Place Cu-BTC in a tube furnace and carbonize at 500°C for 2 h at a heating rate of 5°C / min in a N2 atmosphere. The resulting catalyst is named CuO X / C-500.

[0134] The catalytic activity of the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate was investigated in a 100 mL autoclave. 10 mL of methanol and 0.1 g of catalyst were added to the reactor. 3.6 MPa of CO and 0.4 MPa of O₂ were introduced at room temperature. The reaction was conducted at 300 rpm and 120°C for 2 h. The reaction was then cooled to room temperature and the product composition was analyzed by gas chromatography. The space-time yield of dimethyl carbonate was 634 mg g. -1 ·h -1 , dimethyl carbonate selectivity 100%.

[0135] As shown in Table 1, the evaluation results of the catalyst in the liquid phase oxidative carbonylation of methanol to dimethyl carbonate reaction:

[0136] Table 1: Evaluation results of the catalyst in the liquid phase oxidative carbonylation of methanol to dimethyl carbonate

[0137]

[0138]

[0139] As can be seen from the table above, the maximum space-time yield of dimethyl carbonate is 1295 mg g -1 ·h -1 , which is superior to existing catalysts such as Cu2O / AC catalyst, with a dimethyl carbonate selectivity of 100% and basically no by-products produced.

[0140] Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. Changes and improvements to the present invention will be possible without exceeding the concept and scope specified in the appended claims. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An application of a catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate, characterized in that: The catalyst is a MOFs derivative, with metal oxides dispersed on a carbon support, and the metal oxide is CuO X ; The MOFs derivative is CuO obtained by calcining Cu-MOF. X Dispersed on the carbon support, during the carbonization process Cu 2+ Reduced to Cu and Cu2O; The catalyst has a topological structure and a specific surface area of ​​10 to 150 m 2 ·g -1 The catalyst surface is distributed with mesopores with a pore size of 4 to 35 nm; the catalyst is used for liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate, and the amount of the catalyst used is 1.3% of the mass of methanol.

2. The use of the catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate according to claim 1, characterized in that: The catalyst is prepared by the following method: S101, dissolving copper salt in deionized water to obtain solution A; S102, dissolving H3BTC and PVP in a mixture of deionized water, ethanol, and DMF to obtain solution B; S103, adding solution B to solution A, stirring, and mixing thoroughly to obtain suspension C; S104, transfer suspension C to a hydrothermal reactor and react at 100-150°C for 12-36 hours to obtain solution D with a blue precipitate; S105, centrifuging solution D and washing until the supernatant is colorless; S106, drying the washed product to obtain a blue powdery Cu-MOF; S107. Carbonize the Cu-MOF at high temperature under a N2 atmosphere to obtain a catalyst MOFs derivative.

3. The use of the catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate according to claim 2, characterized in that: The copper salt includes Cu(NO3)2·3H2O.

4. The use of the catalyst for the liquid-phase oxidative carbonylation of methanol to synthesize dimethyl carbonate according to claim 2, characterized in that: In step S102, the volume ratio of deionized water, ethanol and DMF is 1:1:0~1.

5. The use of the catalyst for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate according to claim 2, characterized in that: In step S102, the mass ratio of H3BTC to PVP is 1:0-1.

1.

6. The use of the catalyst for liquid-phase oxidative carbonylation of methanol to dimethyl carbonate according to claim 2, characterized in that: The molar ratio of copper salt to H3BTC in suspension C is 1.5~2:

1.

7. The use of the catalyst for liquid-phase oxidative carbonylation of methanol to dimethyl carbonate according to claim 2, characterized in that: In step S107 , the carbonization temperature is 300-500° C., the heating rate is 3-6° C. / min, and the carbonization time is 1-3 hours.

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