A method for efficient synthesis of vinylene carbonate
By combining a supported silver-based catalyst with a specific structural support, the problem of self-polymerization of vinylene carbonate at high temperatures was solved, achieving efficient synthesis and high-yield production of vinylene carbonate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DALIAN HUAYI LITHIUM BATTERY TECH CO LTD
- Filing Date
- 2026-03-11
- Publication Date
- 2026-06-09
AI Technical Summary
In existing methods for synthesizing vinylene carbonate, self-polymerization easily occurs under high-temperature conditions, leading to a decrease in yield.
A supported silver-based catalyst was used to carry out the reaction in a fixed-bed reactor at low temperature. A support with a specific structure was used to chelate with metallic silver to suppress self-polymerization. The yield of vinylene carbonate was improved by controlling the reaction temperature and flow rate.
The self-polymerization of vinylene carbonate was effectively suppressed at low temperatures, which improved the yield of vinylene carbonate and reduced production costs and energy consumption.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of organic synthesis technology, and in particular to a method for the efficient synthesis of vinylene carbonate. Background Technology
[0002] Vinylene carbonate (VC), with the chemical formula C3H2O3, is an unsaturated organic compound with a unique molecular structure. It is a colorless, transparent liquid at room temperature, exhibits high thermosensitivity, has a melting point between 19 and 22°C, and a boiling point of 162°C. It is stable and insoluble in water. This substance plays a vital role in the chemical industry, especially with the booming development of the lithium battery industry, its synthesis and application have attracted considerable attention.
[0003] The synthesis of vinylene carbonate dates back to the mid-20th century. In 1953, Newman and Alldor first successfully synthesized vinylene carbonate by chlorinating it to produce vinylene monochlorocarbonate, and then removing hydrogen chloride with a dehalogenating agent to obtain the target product. This pioneering research laid the foundation for the subsequent synthesis and application of vinylene carbonate. Since then, with the continuous advancement of lithium-ion battery technology, vinylene carbonate has become an increasingly important additive in lithium-ion battery electrolytes, prompting researchers to continuously explore more efficient, environmentally friendly, and economical synthesis methods.
[0004] In lithium-ion battery systems, vinylene carbonate plays an irreplaceable role. During the initial charge and discharge cycle, the carbon anode material reacts chemically with the organic components in the electrolyte, forming a passivation film, or solid electrolyte interphase (SEI) film, on the surface of the anode material. This film effectively hinders the penetration of solvent molecules while allowing lithium ions to pass freely, significantly impacting battery performance. Vinylene carbonate, as an organic film-forming additive, demonstrates remarkable effectiveness in this regard.
[0005] The preparation methods for vinylene carbonate are now quite mature. For example, patent number CN113816937B discloses a "preparation method for vinylene carbonate" which includes: adding a certain mass of a supported copper-based catalyst, vinylene carbonate, and hydrogen acceptor to a reaction apparatus, and carrying out catalytic dehydrogenation at 200-300°C under a nitrogen atmosphere. The product, vinylene carbonate, is prepared by a hydrogenation coupling reaction. This invention features a simple preparation process, low cost, low reaction temperature, and high yield.
[0006] For example, patent number CN117820281A discloses a "method for preparing vinylene carbonate". The method includes: (1) contacting chloroethylene carbonate with triethylamine at a temperature of 0~100℃ in the presence of a non-reactive solvent to generate a reaction solution containing vinylene carbonate; wherein the non-reactive solvent has a normal pressure boiling point greater than or equal to 200℃ and a density less than 1.2 g / cm³ at 25℃. 3 The method described in this invention eliminates the steps of distillation and rectification of low-boiling-point solvents commonly used in the prior art, shortens the process flow, greatly reduces energy consumption, and improves the purity and yield of vinylene carbonate (VC).
[0007] However, current methods for preparing vinylene carbonate involve high temperatures, and the double bond structure in these methods is prone to self-polymerization at high temperatures, which reduces the yield of vinylene carbonate. Therefore, it is urgent to develop a method that can synthesize vinylene carbonate at low temperatures and avoid self-polymerization. Summary of the Invention
[0008] The purpose of this invention is to provide a method for the efficient synthesis of vinylene carbonate, in order to solve the problem that the yield of vinylene carbonate is reduced due to self-polymerization at high temperatures during the preparation process.
[0009] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for the efficient synthesis of vinylene carbonate, comprising the following steps: using a fixed-bed reactor, loading a supported silver-based catalyst, purging with nitrogen and maintaining a nitrogen atmosphere, introducing ethylene carbonate and furfural into a preheater and heating to 120-130°C, and introducing them into the fixed-bed reactor at flow rates of 4-8 g / min and 5-10 g / min respectively under pressure to contact the supported silver-based catalyst, controlling the temperature of the fixed-bed reactor to carry out the reaction, and cooling the material to room temperature after discharge to obtain vinylene carbonate; The preparation method of the supported silver-based catalyst includes the following steps: under an inert protective gas atmosphere, the support and dichloromethane are mixed, silver oxide is added, and the mixture is stirred at room temperature for 40-48 hours under light-protected conditions. The mixture is then concentrated and dried under reduced pressure to obtain the supported silver-based catalyst.
[0010] Vinylene carbonate has good application value in many fields, and its preparation method is now mature. However, the method of preparing vinylene carbonate using ethylene carbonate as raw material often uses high temperature conditions. Under high temperature conditions, the product vinylene carbonate is prone to double bond polymerization, which affects the yield of vinylene carbonate.
[0011] This application first prepares a supported silver-based catalyst that can be well used in the process of preparing vinylene carbonate from ethylene carbonate. The catalyst has excellent catalytic performance, which can not only reduce the reaction temperature, but also inhibit the polymerization of vinylene carbonate, thereby improving the yield of vinylene carbonate.
[0012] In some embodiments, the inert protective gas is nitrogen or argon.
[0013] Preferably, the inert protective gas is nitrogen.
[0014] In some embodiments, the temperature of the fixed-bed reactor is 130~140°C.
[0015] Preferably, the temperature of the reactor is 135°C.
[0016] This application, by controlling the reaction temperature, can further reduce the occurrence of self-polymerization of the product vinylene carbonate while ensuring the smooth progress of the reaction.
[0017] In some embodiments, the mass ratio of ethylene carbonate to furfural is 1:(1.2~1.4).
[0018] Preferably, the mass ratio of ethylene carbonate to furfural is 1:1.3.
[0019] In some embodiments, the carrier has the following structure: (I).
[0020] In some embodiments, the method for preparing the carrier includes the following steps: S1. Under an inert protective gas atmosphere, p-aldehyde benzoic acid, dicyclohexylcarbodiimide, tert-butanol and 4-dimethylaminopyridine were mixed and added to dichloromethane. The mixture was heated to 25~30℃ and stirred at a constant temperature for 10~14h. The mixture was concentrated under reduced pressure, extracted, subjected to column chromatography, concentrated under reduced pressure and dried to obtain tert-butyl 4-formylbenzoate. S2. Under an inert protective gas atmosphere, a mixture of tert-butyl 4-formylbenzoate, pyrrole, and boron trifluoride diethyl ether complex was added to chloroform, heated to 40-60°C, and stirred for 1-2 hours. Then, 2,3-dichloro-5,6-dicyanobenzoquinone was added, and stirring continued for 3-4 hours to obtain the compound shown in Formula II. (II); S3. Mix the compound of formula II obtained in step S2 with concentrated sulfuric acid, add potassium nitrate and dichloromethane, cool to -5~0℃ and stir for 2~3 hours. After the mixture is finished, extract, concentrate and dry under reduced pressure to obtain the compound of formula III. (III); S4. Mix the compound of formula III obtained in step S3 with N,N-dimethylformamide, add concentrated sulfuric acid and piperidinol oxide, heat to 60~80℃, stir at a constant temperature for 4~6h, concentrate and dry under reduced pressure to obtain the support.
[0021] This application describes a method for preparing a support with a specific structure, in which metallic silver is used as a catalyst and chelated with the amine groups in the support. This improves the catalytic efficiency of the catalyst and, at the same time, the structure contains a large number of polymerization inhibitory groups, which greatly enhances the self-polymerization behavior of the product vinylene carbonate under high-temperature processes, thereby increasing the yield of vinylene carbonate.
[0022] In some embodiments, in step S2, the molar ratio of tert-butyl 4-formylbenzoate to pyrrole is 1:(1~1.2).
[0023] Preferably, in step S2, the molar ratio of tert-butyl 4-formylbenzoate to pyrrole is 1:1.1.
[0024] This application first reacts tert-butanol with p-aldehyde benzoic acid to protect the carboxyl group and prevent subsequent condensation reaction with the amine group. At the same time, by adjusting the molar ratio of tert-butyl 4-formylbenzoate and pyrrole, a symmetrical structure with four active centers in a "head-to-head" configuration can be obtained, in which silver ions can be stably chelated.
[0025] In some embodiments, in step S4, the molar ratio of the compound represented by Formula III to piperidine oxide is 1:(4~5).
[0026] Preferably, in step S4, the molar ratio of the compound represented by Formula III to piperidine oxide is 1:4.
[0027] This application improves the polymerization inhibition performance of the support by adjusting the molar ratio of the compound shown in Formula III to piperidinol oxide, thereby enabling all four active carboxyl groups in the compound structure shown in Formula III to be grafted with piperidinol oxide structure.
[0028] In some embodiments, the mass ratio of the carrier to silver oxide is 1:(0.3~0.5).
[0029] Preferably, the mass ratio of the carrier to silver oxide is 1:0.4.
[0030] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention first prepared a supported silver-based catalyst that can be well used in the process of preparing vinylene carbonate from ethylene carbonate. The catalyst has excellent catalytic performance, which can not only reduce the reaction temperature, but also inhibit the polymerization of vinylene carbonate, thereby improving the yield of vinylene carbonate.
[0031] (2) By controlling the reaction temperature, the present invention can further reduce the occurrence of self-polymerization of the product vinylene carbonate while ensuring the smooth progress of the reaction.
[0032] (3) The present invention provides a carrier with a specific structure, and uses metallic silver as a catalyst to chelate and load the amine groups in the carrier. The catalytic efficiency of the catalyst is improved. At the same time, the structure contains a large number of polymerization inhibitor groups, which greatly improves the self-polymerization behavior of the product vinylene carbonate under high temperature process, thereby improving the yield of vinylene carbonate. Detailed Implementation
[0033] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.
[0034] Unless otherwise specified, the post-processing operations described below, such as "mixing", "reduced pressure distillation", "filtration", "sedimentation", "washing", "ultrasonic vibration", "drying", "heating", "stirring", and "baking", can be selected by those skilled in the art based on actual conditions, and are not further limited.
[0035] Boron trifluoride diethyl ether complex CAS: 109-63-7; X-type molecular sieve purchased from Zhengzhou Chaorong Nanomaterials Co., Ltd.
[0036] Preparation Example 1 The method for preparing the carrier includes the following steps: S1. Under a N2 atmosphere, 0.1 mol of p-aldehyde benzoic acid, 0.15 mol of dicyclohexylcarbodiimide, 1 mol of tert-butanol and 0.83 mol of 4-dimethylaminopyridine were mixed and added to 500 ml of dichloromethane. The mixture was heated to 27 °C and stirred for 12 h. The mixture was then concentrated under reduced pressure, extracted (chloroform / deionized water containing 4 M HCl), and subjected to column chromatography (n-hexane / dichloromethane). The mixture was then concentrated under reduced pressure and dried to obtain tert-butyl 4-formylbenzoate. S2. Under a nitrogen atmosphere, 0.1 mol of tert-butyl 4-formylbenzoate, 0.11 mol of pyrrole, and 0.04 mol of boron trifluoride diethyl ether complex were mixed and added to 500 mL of chloroform. The mixture was heated to 50 °C and stirred for 1.5 h. Then, 0.1 mol of 2,3-dichloro-5,6-dicyanobenzoquinone was added and the mixture was stirred for another 3.5 h to obtain the compound shown in Formula II. (II); The NMR analysis of the compound represented by Formula II is as follows: 1 H NMR (400 MHz, DMSO-d6) δ 11.01 (s,1H), 9.31 (s, 1H), 8.82 (d, J = 2.1 Hz, 6H), 8.02 – 7.93 (m, 8H), 7.89 (s,2H), 7.83 – 7.66 (m, 8H), 1.55 (s, 36H); S3. Mix 0.1 mol of the compound of formula II obtained in step S2 with 10 ml of 96 wt% concentrated sulfuric acid, add 4 g of potassium nitrate and 400 ml of dichloromethane, cool to -3 °C and stir at a constant temperature for 2.5 h. After the mixture is removed, extract with ethyl acetate / deionized water, concentrate under reduced pressure and dry to obtain the compound of formula III. (III); The NMR analysis of the compound represented by Formula III is as follows: 1 H NMR (400 MHz, DMSO-d6) δ 12.73 (s,4H), 11.01 (s, 1H), 9.31 (s, 1H), 8.82 (d, J = 2.1 Hz, 6H), 8.02 – 7.93 (m,8H), 7.89 (s, 2H), 7.83 – 7.76 (m, 4H), 7.73 – 7.65 (m, 4H); S4. Mix 0.1 mol of the compound of formula III obtained in step S3 with 300 ml of N,N-dimethylformamide, add 2.6 ml of 98 wt% concentrated sulfuric acid and 0.4 mol of piperidinol oxide, heat to 70 °C, stir at a constant temperature for 5 h, concentrate and dry under reduced pressure to obtain the support.
[0037] Preparation Example 2 The preparation method of the carrier is the same as that in Preparation Example 1, except that the pyrrole content is 0.05 mol.
[0038] Preparation Example 3 The preparation method of the carrier is the same as that in Preparation Example 1, except that the amount of piperidinol oxide is 0.3 mol.
[0039] Example 1 A method for the efficient synthesis of vinylene carbonate includes the following steps: a fixed-bed reactor is used, loaded with a supported silver-based catalyst (30 ml loading volume), purged with nitrogen and maintained under a nitrogen atmosphere, 360 g of vinylene carbonate and 468 g of furfural are introduced into a preheater and heated to 125 °C, and then introduced into the fixed-bed reactor at a flow rate of 6 g / min and 8 g / min respectively under a pressure of 0.15 MPa to contact the supported silver-based catalyst, the temperature of the fixed-bed reactor is controlled at 135 °C for reaction, and after discharge, the mixture is cooled to room temperature to obtain vinylene carbonate; The preparation method of the supported silver-based catalyst includes the following steps: under N2 atmosphere, 10g of support and 100ml of dichloromethane are mixed, 4g of silver oxide is added, and the mixture is stirred at room temperature for 44h under light-protected conditions. The mixture is then concentrated and dried under reduced pressure to obtain the supported silver-based catalyst.
[0040] The carrier was prepared according to Preparation Example 1.
[0041] The yield of vinylene carbonate was 92.8% as determined by gas chromatography.
[0042] Example 2 A method for the efficient synthesis of vinylene carbonate includes the following steps: a fixed-bed reactor is used, loaded with a supported silver-based catalyst (loading volume 20 ml), purged with nitrogen and maintained under a nitrogen atmosphere, 240 g of vinylene carbonate and 312 g of furfural are introduced into a preheater and heated to 120 °C, and then introduced into the fixed-bed reactor at a flow rate of 4 g / min and 5 g / min respectively under a pressure of 0.1 MPa to contact the supported silver-based catalyst, the temperature of the fixed-bed reactor is controlled at 130 °C for reaction, and after discharge, the mixture is cooled to room temperature to obtain vinylene carbonate; The preparation method of the supported silver-based catalyst includes the following steps: under N2 atmosphere, 10g of support and 100ml of dichloromethane are mixed, 3g of silver oxide is added, and the mixture is stirred at room temperature for 40h under light-protected conditions. The mixture is then concentrated and dried under reduced pressure to obtain the supported silver-based catalyst.
[0043] The carrier was prepared according to Preparation Example 1.
[0044] The yield of vinylene carbonate was 91.9% as determined by gas chromatography.
[0045] Example 3 A method for the efficient synthesis of vinylene carbonate includes the following steps: a fixed-bed reactor is used, loaded with a supported silver-based catalyst (40 ml loading volume), purged with nitrogen and maintained under a nitrogen atmosphere, 480 g of vinylene carbonate and 624 g of furfural are introduced into a preheater and heated to 130 °C, and then introduced into the fixed-bed reactor at a flow rate of 8 g / min and 10 g / min respectively under a pressure of 0.2 MPa to contact the supported silver-based catalyst, the temperature of the fixed-bed reactor is controlled at 140 °C for reaction, and after discharge, the mixture is cooled to room temperature to obtain vinylene carbonate; The preparation method of the supported silver-based catalyst includes the following steps: under N2 atmosphere, 10g of support and 100ml of dichloromethane are mixed, 5g of silver oxide is added, and the mixture is stirred at room temperature for 48h under light-protected conditions. The mixture is then concentrated and dried under reduced pressure to obtain the supported silver-based catalyst.
[0046] The carrier was prepared according to Preparation Example 1.
[0047] The yield of vinylene carbonate was 92.4% as determined by gas chromatography.
[0048] Example 4 A method for the efficient synthesis of vinylene carbonate, the specific implementation method is the same as in Example 1, except that the support is prepared in Preparation Example 2.
[0049] The yield of vinylene carbonate was 88.9% as determined by gas chromatography.
[0050] Example 5 A method for the efficient synthesis of vinylene carbonate is described, with the specific implementation method being the same as in Example 1, except that the support is prepared in Preparation Example 3.
[0051] The yield of vinylene carbonate was 84.1% as determined by gas chromatography.
[0052] Example 6 A method for the efficient synthesis of vinylene carbonate, the specific implementation method is the same as in Example 1, except that X-type molecular sieve is used as the support.
[0053] The yield of vinylene carbonate was 79.8% as determined by gas chromatography.
[0054] Comparative Example 1 A method for the efficient synthesis of vinylene carbonate, the specific implementation method is the same as in Example 1, except that silver oxide is used instead of a supported silver-based catalyst.
[0055] The yield of vinylene carbonate was 66.3% as determined by gas chromatography.
[0056] Comparative Example 2 A method for the efficient synthesis of vinylene carbonate, the specific implementation method is the same as in Example 1, except that a supported copper-based catalyst is used instead of a supported silver-based catalyst.
[0057] The preparation method of the supported copper-based catalyst includes the following steps: Under a N2 atmosphere, 10g of support and 100ml of dichloromethane are mixed, 5g of copper nitrate is added, the mixture is stirred at room temperature for 48h, and then concentrated and dried under reduced pressure to obtain the supported copper-based catalyst. Gas chromatography analysis showed that the yield of vinylene carbonate was 88.5%.
[0058] Based on the detection data from the above examples and comparative methods, it can be seen that the methods for the efficient synthesis of vinylene carbonate in Examples 1-3 yielded higher yields of vinylene carbonate. In Example 4, the change in the molar ratio of tert-butyl 4-formylbenzoate and pyrrole led to a decrease in the loading capacity of metallic silver in the supported silver-based catalyst, thus resulting in a lower yield of vinylene carbonate. In Example 5, the change in the molar ratio of the compound shown in Formula III to piperidinol oxide led to a decrease in the inhibitory ability of the supported silver-based catalyst on the product vinylene carbonate, thus resulting in a lower yield of vinylene carbonate. In Example 6, the use of X-type molecular sieves as a support... The reduced ability of the supported silver-based catalyst to inhibit the polymerization of vinylene carbonate resulted in a decrease in the yield of vinylene carbonate. In Comparative Example 1, silver oxide was used instead of the supported silver-based catalyst. Since the silver oxide catalyst does not inhibit the polymerization of vinylene carbonate, self-polymerization of vinylene carbonate occurred at high temperatures. Furthermore, at the same temperature, the catalytic performance of silver oxide was weaker than that of the supported silver-based catalyst, resulting in a significant decrease in the yield of vinylene carbonate. In Comparative Example 2, copper-based catalyst was used instead of the supported silver-based catalyst. Since the catalytic performance of copper was weaker than that of silver, the yield of vinylene carbonate was also reduced.
[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. A method for the efficient synthesis of vinylene carbonate, characterized in that, The process includes the following steps: A fixed-bed reactor is used, loaded with a supported silver-based catalyst, purged with nitrogen and maintained in a nitrogen atmosphere, ethylene carbonate and furfural are introduced into a preheater and heated to 120-130°C, and then introduced into the fixed-bed reactor at flow rates of 4-8 g / min and 5-10 g / min respectively under pressure to contact the supported silver-based catalyst. The temperature of the fixed-bed reactor is controlled to carry out the reaction, and after discharge, the mixture is cooled to room temperature to obtain ethylene carbonate. The preparation method of the supported silver-based catalyst includes the following steps: under an inert protective gas atmosphere, the support and dichloromethane are mixed, silver oxide is added, and the mixture is stirred at room temperature for 40-48 hours under light-protected conditions. The mixture is then concentrated and dried under reduced pressure to obtain the supported silver-based catalyst.
2. The method for efficient synthesis of vinylene carbonate according to claim 1, characterized in that, The inert protective gas is nitrogen or argon.
3. The method for efficient synthesis of vinylene carbonate according to claim 1, characterized in that, The temperature of the fixed-bed reactor is 130~140℃.
4. The method for efficient synthesis of vinylene carbonate according to claim 1, characterized in that, The mass ratio of ethylene carbonate to furfural is 1:(1.2~1.4).
5. The method for efficient synthesis of vinylene carbonate according to claim 1, characterized in that, The pressure is 0.1~0.2 MPa.
6. The method for efficient synthesis of vinylene carbonate according to claim 1, characterized in that, The carrier has the following structure: （Ⅰ）。 7. The method for efficient synthesis of vinylene carbonate according to claim 6, characterized in that, The method for preparing the carrier includes the following steps: S1. Under an inert protective gas atmosphere, p-aldehyde benzoic acid, dicyclohexylcarbodiimide, tert-butanol and 4-dimethylaminopyridine were mixed and added to dichloromethane. The mixture was heated to 25~30℃ and stirred at a constant temperature for 10~14h. The mixture was concentrated under reduced pressure, extracted, subjected to column chromatography, concentrated under reduced pressure and dried to obtain tert-butyl 4-formylbenzoate. S2. Under an inert protective gas atmosphere, a mixture of tert-butyl 4-formylbenzoate, pyrrole, and boron trifluoride diethyl ether complex was added to chloroform, heated to 40-60°C, and stirred for 1-2 hours. Then, 2,3-dichloro-5,6-dicyanobenzoquinone was added, and stirring continued for 3-4 hours to obtain the compound shown in Formula II. （Ⅱ）； S3. Mix the compound of formula II obtained in step S2 with concentrated sulfuric acid, add potassium nitrate and dichloromethane, cool to -5~0℃ and stir for 2~3 hours. After the mixture is finished, extract, concentrate and dry under reduced pressure to obtain the compound of formula III. （Ⅲ）； S4. Mix the compound of formula III obtained in step S3 with N,N-dimethylformamide, add concentrated sulfuric acid and piperidinol oxide, heat to 60~80℃, stir at a constant temperature for 4~6h, concentrate and dry under reduced pressure to obtain the support.
8. The method for efficient synthesis of vinylene carbonate according to claim 7, characterized in that, In step S2, the molar ratio of tert-butyl 4-formylbenzoate to pyrrole is 1:(1~1.2).
9. The method for efficient synthesis of vinylene carbonate according to claim 7, characterized in that, In step S4, the molar ratio of the compound represented by Formula III to piperidine oxide is 1:(4~5).
10. The method for efficient synthesis of vinylene carbonate according to claim 1, characterized in that, The mass ratio of the carrier to silver oxide is 1:(0.3~0.5).