METHOD OF PREPARING HETEROGENEOUS LINEAR CARBONATE USING CATALYST HAVING EXCELLENT SOLUBILITY

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.

Claims

1. A method of preparing a heterogeneous linear carbonate, 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.sup.1S(O)R.sup.2[Chemical Formula 1] in Chemical Formula 1, R.sup.1 and R.sup.2 are each independently a substituted or unsubstituted C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.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

EXAMPLE 1

[0044] 135.12 g of dimethyl carbonate (DMC), 90.16 g of ethanol (EtOH), and 13.5 g of a sodium methoxide solution (SME, 1 wt % in dimethyl sulfoxide (DMSO)) as raw materials were reacted by stirring at a rate of 200 rpm at 70 C. and 1 bar for 1 hour.

[0045] In order to confirm the effect of the present invention through a simple experiment, the raw materials were reacted using a batch reactor, and ethyl methyl carbonate and diethyl carbonate were synthesized.

EXAMPLE 2

[0046] Ethyl methyl carbonate and diethyl carbonate were synthesized in the same manner as in Example 1, except that 13.5 g of a sodium hydroxide solution (NaOH, 1 wt % in dimethyl sulfoxide (DMSO)) was applied instead of 13.5 g of a sodium methoxide solution (SME, 1 wt % in dimethyl sulfoxide (DMSO)).

EXAMPLE 3

[0047] The raw materials were stirred and reacted as in Example 1 using 13.5 g of a sodium hydroxide solution (NaOH, 1 wt % in dimethyl sulfoxide (DMSO)).

[0048] Then, the reaction concentrate produced after the reaction was distilled, 135.12 g of dimethyl carbonate (DMC) and 103.66 g of ethanol (EtOH) were input again as the same raw materials using the residue, and reacted by stirring under the same conditions.

COMPARATIVE EXAMPLE 1

[0049] Ethyl methyl carbonate and diethyl carbonate were synthesized in the same manner as in Example 1, except that 13.5 g of a sodium methoxide solution (SME, 1 wt % in ethanol (EtOH)) was applied instead of 13.5 g of a sodium methoxide solution (SME, 1 wt % in dimethyl sulfoxide (DMSO)).

COMPARATIVE EXAMPLE 2

[0050] Ethyl methyl carbonate and diethyl carbonate were synthesized in the same manner as in Example 1, except that 13.5 g of a sodium hydroxide solution (NaOH, 1 wt % in ethanol (EtOH)) was applied instead of 13.5 g of a sodium methoxide solution (SME, 1 wt % in dimethyl sulfoxide (DMSO)).

EXPERIMENTAL EXAMPLE 1

[0051] Qualitative and quantitative analyses were performed on the consumption of dimethyl carbonate as a raw material for preparation and amounts of ethyl methyl carbonate and diethyl carbonate as desired products in Examples 1 to 3 and Comparative Examples 1 and 2, and results are shown in Table 1 below.

[0052] For the qualitative and quantitative analyses, after passing the obtained compound through a filter, 1 g of a product passed through the filter was taken and mixed with 0.1 g of m-xylene, and then the concentration was measured using gas chromatography (GC) (YL6500GC manufactured by YOUNG IN Chromass Co., GC column: DB-1 30 m0.53 mm, GC detector: FID). In addition, a reaction conversion rate of dimethyl carbonate as a raw material for preparation was calculated as mol % based on a consumption amount compared to an amount used, and the reaction selectivity of ethyl methyl carbonate and diethyl carbonate as desired products was calculated as mol % based on a total content of ethyl methyl carbonate and diethyl carbonate respectively produced.

[0053] In addition, after distilling the reaction concentrate generated after the reaction, residues were filtered using a 0.45 m syringe filter, and then a weight of solid particles remaining in the filter was measured. The results are shown in Table 1 below.

TABLE-US-00001 TABLE 1 Comparative Comparative Classification Example 1 Example 2 Example 3 Example 1 Example 2 Activity DMC 65 66 64 63 64 results conversion rate [%] EMC 74 73 75 76 73 selectivity [%] DEC 26 27 25 24 27 selectivity [%] Amount of solid catalyst 0.017 0.015 0.127 0.122 in residue [g]

[0054] According to Table 1, when the reaction is performed by the method according to the present invention, it can be confirmed that the activity of the catalyst is the same as in the case of the conventional method, but the precipitation of the catalyst is significantly reduced and there is almost no precipitation, and, as can be seen from Example 3, since almost the same activity can be obtained even when the catalyst is reused, the reuse efficiency is very excellent.