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CN-121988389-A - Homogeneous catalyst derived from carbon dioxide immobilized product, preparation method and application thereof in synthesis of dimethyl carbonate

CN121988389ACN 121988389 ACN121988389 ACN 121988389ACN-121988389-A

Abstract

The invention relates to the technical field of organic synthesis, in particular to a homogeneous catalyst derived from a carbon dioxide fixed product, a preparation method and application thereof in synthesizing dimethyl carbonate, wherein the catalyst is obtained by stirring and reacting organic secondary amine and cyclic carbonate for 1-6 hours at 110-160 ℃ in a molar ratio of 0.6-1.3:1. And (3) stirring and reacting for 3.5-7.5 hours at 60-75 ℃ according to the molar ratio of the methanol to the cyclic carbonate of 4-15:1 and the catalyst dosage of 0.3-12%, and distilling the reaction mixture at normal pressure to obtain the mixture containing the target product dimethyl carbonate. The catalyst provided by the invention has higher catalytic activity, stability and water resistance, and can be used for efficiently catalyzing ethylene carbonate and methanol to synthesize dimethyl carbonate in a homogeneous catalysis mode.

Inventors

  • ZENG JIE
  • YANG JIANGUO
  • ZHANG HONGBO
  • LIU MINGKAI

Assignees

  • 安徽工业大学

Dates

Publication Date
20260508
Application Date
20260410

Claims (8)

  1. 1. A process for the preparation of a homogeneous catalyst derived from a carbon dioxide fixation product, comprising the steps of: s1, mixing organic secondary amine and cyclic carbonate, and stirring and reacting for 1-6 hours at 110-160 ℃; s2, cooling the material reacted in the step S1 to room temperature to obtain the homogeneous catalyst derived from the carbon dioxide immobilized product.
  2. 2. The method for preparing a homogeneous catalyst derived from a carbon dioxide fixation product according to claim 1, wherein in the step S1, the secondary organic amine is a compound of the formula Any one of secondary organic amines or a mixture of secondary organic amines, wherein R 1 、R 2 is independently selected from alkyl groups having 3 or more carbon atoms.
  3. 3. The method for preparing a homogeneous catalyst derived from a carbon dioxide fixation product according to claim 1, wherein in the step S1, the cyclic carbonate is any one or a mixture of two of ethylene carbonate and propylene carbonate as the carbon dioxide fixation product.
  4. 4. The method for preparing a homogeneous catalyst derived from a carbon dioxide fixation product according to claim 1, wherein in the step S1, the molar ratio of the secondary organic amine to the cyclic carbonate is 0.6-1.3:1.
  5. 5. A homogeneous catalyst derived from a carbon dioxide fixation product obtained by the production method according to any one of claims 1 to 4.
  6. 6. Use of a homogeneous catalyst derived from carbon dioxide fixation products according to claim 5 for the synthesis of dimethyl carbonate, characterized in that the method of application comprises in particular the following steps: a1, uniformly mixing cyclic carbonate, methanol and a homogeneous catalyst, and stirring and refluxing at 60-75 ℃ for 3.5-7.5 hours; A2, cooling the material reacted in the step A1 to room temperature, distilling at normal pressure, and collecting mixed fraction consisting of methanol and target product dimethyl carbonate within the range of 64-91 ℃.
  7. 7. The use of a homogeneous catalyst derived from carbon dioxide fixation products in the synthesis of dimethyl carbonate according to claim 6, wherein in step A1 the cyclic carbonate is any one or a mixture of two of ethylene carbonate and propylene carbonate.
  8. 8. The use of a homogeneous catalyst derived from carbon dioxide fixation products according to claim 6 for synthesizing dimethyl carbonate, wherein in the step A1, the molar ratio of methanol to cyclic carbonate is 4-15:1, and the amount of the homogeneous catalyst is 0.3-12% of the total mass of methanol and cyclic carbonate.

Description

Homogeneous catalyst derived from carbon dioxide immobilized product, preparation method and application thereof in synthesis of dimethyl carbonate Technical Field The invention relates to the technical field of organic synthesis, in particular to a homogeneous catalyst derived from a carbon dioxide fixed product, a preparation method and application thereof in synthesizing dimethyl carbonate. Background Dimethyl carbonate (DMC) can be used as an organic synthesis intermediate, an environment-friendly solvent, a gasoline additive and a lithium battery electrolyte solvent, is an important green chemical raw material, and is synthesized by a phosgene method, an oxidative carbonylation method, an ester exchange method and the like, wherein the ester exchange method utilizes Propylene Carbonate (PC) or Ethylene Carbonate (EC) in cyclic carbonate to carry out ester exchange reaction with methanol (MeOH) to synthesize DMC. Compared with phosgene method and high-energy-consumption oxidative carbonylation method which depend on highly toxic raw materials, the transesterification method has the advantages of mild reaction conditions and convenient implementation, and the PC or EC raw materials used are derived from addition products of CO 2 and propylene oxide or ethylene oxide. Therefore, the synthesis of DMC by transesterification essentially belongs to the extension of the CO 2 resource utilization technology chain, and can provide strong technical support for carbon emission reduction. According to the dissolution state of the catalyst in the reaction system, the catalyst for transesterification reaction comprises (1) homogeneous catalysts such as strong alkaline compounds sodium hydroxide (potassium) and sodium alkoxide, sodium carbonate (potassium), ionic liquid and the like, and (2) heterogeneous catalysts such as modified molecular sieves, alkaline ion exchange resins, solid base catalysts, solid supported ionic liquid and the like. Heterogeneous catalysts, although easy to separate, have not been applied to industrial production on a large scale due to low activity, short life, high cost, etc. The method is limited by cost and manufacturability factors, and the sodium methoxide homogeneous catalyst is mainly adopted for synthesizing the dimethyl carbonate by the industrialized transesterification method at present. Although the catalytic activity of sodium methoxide is relatively high, the sodium methoxide has the defects of larger polarity difference between sodium methoxide and reaction materials, limited solubility in a reaction system, easy crystallization and precipitation, easy reaction between sodium methoxide, organic carbonate and moisture and conversion into sodium carbonate solid with lower solubility, blockage of a production device and reduction of production efficiency although the sodium carbonate can maintain certain catalytic activity, strong corrosiveness, inconvenient feeding and storage and transportation difficulties, and high production efficiency. Therefore, the development of the novel transesterification catalyst which has strong solubility, high activity and high stability and is insensitive to water has important application value, is beneficial to overcoming the defects of sodium alkoxide catalysts and promotes the industrial technology to be upgraded. In view of the above drawbacks, the present inventors have finally achieved the present invention through long-time studies and practices. Disclosure of Invention The invention aims to solve the problems of limited solubility, sensitivity to water, easiness in causing blockage of production devices, inconvenient feeding and high storage and transportation difficulty of the existing sodium alkoxide catalyst, and provides a homogeneous catalyst derived from a carbon dioxide fixed product, a preparation method and application of the homogeneous catalyst in synthesizing dimethyl carbonate. In order to achieve the above object, the present invention discloses a method for preparing a homogeneous catalyst derived from a carbon dioxide fixation product, comprising the steps of: S1, mixing organic secondary amine and cyclic carbonate, and stirring and refluxing at 110-160 ℃ for reaction for 1-6 hours; s2, cooling the material reacted in the step S1 to room temperature to obtain the homogeneous catalyst derived from the carbon dioxide immobilized product. In the step S1, the secondary organic amine is a compound conforming to the structural formulaAny one of secondary organic amines or a mixture of secondary organic amines, wherein R 1、R2 is independently selected from alkyl groups having 3 or more carbon atoms. In the step S1, the cyclic carbonate is any one or a mixture of two of ethylene carbonate and propylene carbonate which are carbon dioxide fixed products. In the step S1, the molar ratio of the secondary organic amine to the cyclic carbonate is 0.6-1.3:1. The invention also discloses a homogeneous catalyst derived from the carbon di