US-12623994-B2 - Method of preparing heterogeneous linear carbonate using catalyst having excellent solubility

US12623994B2US 12623994 B2US12623994 B2US 12623994B2US-12623994-B2

Abstract

The present invention relates to a method of preparing a heterogeneous linear carbonate, the method including performing a transesterification reaction of dimethyl carbonate (DMC) and ethanol (EtOH) in the presence of a catalyst, wherein the catalyst is one or more selected from the group consisting of lithium methoxide (LME), lithium ethoxide (LEE), sodium methoxide (SME), sodium hydroxide (NaOH), and a mixture thereof, and the catalyst is input in a state of being dissolved in a sulfoxide-based solvent.

Inventors

Wang Gyu KIM
Mi Hwa Baek
Jong Myung Choi
Eun Hye HAN
Jin Hyung Kim

Assignees

LOTTE CHEMICAL CORPORATION

Dates

Publication Date: 20260512
Application Date: 20211105
Priority Date: 20201126

Claims (7)

1 . A method of preparing ethyl methyl carbonate (EMC) and diethyl carbonate (DEC), comprising performing a transesterification reaction of dimethyl carbonate (DMC) and ethanol (EtOH) in the presence of a catalyst, wherein the catalyst is one or more selected from the group consisting of lithium methoxide (LME), lithium ethoxide (LEE), sodium methoxide (SME), sodium hydroxide (NaOH), and a mixture thereof, and the catalyst is input in a state of being dissolved in a sulfoxide-based solvent.
2 . The method of claim 1 , wherein the catalyst is one or more selected from the group consisting of sodium methoxide (SME), sodium hydroxide (NaOH), and a mixture thereof.
3 . The method of claim 1 , wherein the sulfoxide-based solvent is represented by Chemical Formula 1 below: R 1 —S(═O)—R 2 [Chemical Formula 1] in Chemical Formula 1, R 1 and R 2 are each independently a substituted or unsubstituted C 1 -C 10 alkyl, C 3 -C 8 cycloalkyl, heterocycloalkyl, aryl, or heteroaryl group.
4 . The method of claim 3 , wherein the sulfoxide-based solvent is dimethyl sulfoxide (DMSO).
5 . The method of claim 1 , wherein the catalyst is input in a state of being dissolved in the sulfoxide-based solvent in an amount of 0.1% by weight or more and 3% by weight or less.
6 . The method of claim 1 , wherein the catalyst is input in an amount of 0.001% by weight or more and 3% by weight or less, based on a weight of dimethyl carbonate.
7 . The method of claim 1 , wherein the transesterification reaction is performed in a continuous stirred tank reactor (CSTR).

Description

TECHNICAL FIELD The present invention relates to a method of preparing a heterogeneous linear carbonate using a catalyst having excellent solubility. BACKGROUND ART It is well known that a method of preparing ethyl methyl carbonate (EMC) and diethyl carbonate (DEC), which are used as organic solvents for battery electrolytes, is through a transesterification reaction of dimethyl carbonate (DMC) and ethanol. At this time, a catalyst is used for the reaction, and as the catalyst, sodium methoxide (NaOCH3, SME) and sodium hydroxide (NaOH), which have excellent activity, are mainly used. However, since the SME or NaOH has low solubility in organic solvents and is insoluble in DMC, EMC, and DEC, it causes column plugging in a reactive distillation process or a purification process, so that process trouble occurs. In this regard, in Patent Document 1, EMC and DEC are prepared through a reactive distillation method using DMC, an alcohol, and a catalyst. Referring to the drawings, there is a strainer at the rear of a reactive distillation column to separate the solid phase, but when the alcohol is distilled in the reactive distillation column, the catalyst is eventually precipitated, so that powder builds up on the packing inside the column and still causes plugging. In addition, Patent Document 2 discloses that DEC is produced at a high rate by utilizing the SME catalyst and reactive distillation, wherein the inside of a reactive distillation column is composed of a porous tray, the catalyst is input in a mixed state of SME and an alcohol such as ethanol, but in this method, after the alcohol is distilled inside the reactive distillation column, the catalyst is precipitated from the bottom concentrate, causing plugging, and even if the catalyst passes to the downstream separation process, not only problems are expected inside an EMC purification tower, but also during DEC purification, there is a problem of loss of DEC due to precipitated SME. Therefore, there is a need for research on a method for effectively preparing a heterogeneous linear carbonate for a battery electrolyte by solving the above problems. RELATED ART DOCUMENTS Patent Documents (Patent Document 1) Chinese Patent Publication No. 103804124(Patent Document 2) Korean Patent Publication No. 10-1668571 DISCLOSURE Technical Problem The present invention is directed to providing a method a preparing a heterogeneous linear carbonate, wherein the method uses a sulfoxide-based solvent with excellent catalyst solubility, and the catalyst does not precipitate even in a purification process, thereby reducing maintenance costs and having excellent economic efficiency because the catalyst can be reused. Technical Solution One embodiment of the present invention provides a method of preparing a heterogeneous linear carbonate, the method including performing a transesterification reaction of dimethyl carbonate (DMC) and ethanol (EtOH) in the presence of a catalyst, wherein the catalyst is one or more selected from the group consisting of lithium methoxide (LME), lithium ethoxide (LEE), sodium methoxide (SME), sodium hydroxide (NaOH), and a mixture thereof, and the catalyst is input in a state of being dissolved in a sulfoxide-based solvent. Advantageous Effects A method of preparing a heterogeneous linear carbonate according to the present invention minimizes process problems by effectively preventing catalyst precipitation during a distillation process to prevent column plugging by inputting a catalyst in a state of being dissolved in a sulfoxide-based solvent having excellent catalyst solubility during a transesterification reaction, and thus has effects of reducing maintenance costs and remarkably improving the reuse efficiency of the catalyst. Modes of the Invention Throughout the specification, when a part is said to “include” a component, this means that the part may further include other components rather than excluding other components unless specifically stated to the contrary. In the present specification, the unit “% by weight” may mean the ratio of the weight of a certain component to all components. Hereinafter, the present invention will be described in detail. One embodiment of the present invention provides a method of preparing a heterogeneous linear carbonate, the method including performing a transesterification reaction of dimethyl carbonate (DMC) and ethanol (EtOH) in the presence of a catalyst, wherein the catalyst is one or more selected from the group consisting of lithium methoxide (LME), lithium ethoxide (LEE), sodium methoxide (SME), sodium hydroxide (NaOH), and a mixture thereof, and the catalyst is input in a state of being dissolved in a sulfoxide-based solvent. In the present invention, the heterogeneous linear carbonate means a carbonate of a different species from the dimethyl carbonate, specifically, a symmetric linear carbonate and an asymmetric linear carbonate, and more specifically, ethyl methyl carbonate (EMC) and diethyl ca