酯交换法合成碳酸二甲酯过程产物的气相色谱分析

Determination of the components in transesterification synthesis of dimethyl carbonate by gas chromatography

采用HP-FFAP毛细柱,建立了一种同时定量测定一步酯交换法合成碳酸二甲酯过程产物的色谱分析方法.考察了柱温对分离效果的影响,确定了适宜的操作条件.结果表明,在所确定的操作条件下,反应混合物中的环氧乙烷、甲醇、碳酸二甲酯、乙二醇单甲醚、乙二醇和碳酸乙烯酯等组分峰都可以较好地分开,且峰形好;定量测定各组分含量的重现性相对标准偏差(RSD)均小于5%,准确性相对误差均小于3%,表明所建立的分析方法可以较好地满足工业生产过程控制分析的要求.

A new method for quantitative determination of dimethyl carbonate mixture, which was prepared by one-step transesterification of ethylene oxide, CO2 and methanol, was established on a gas chromatography with a capillary column （HP-FFAP）. The Effect of ramp rate of column temperature on the separation efficiency was investigated and the appropriate operation conditions were given. Under the given conditions, the components in the mixture, including ethylene oxide, methanol, dimethyl carbonate, 2-methoxyethanol, ethylene glycol and ethylene carbonate, can be separated efficiently with good peak shapes. For each component, the relative standard deviations （RSD） in repeatability and relative errors in accuracy were less than 5% and 3% respectively. Thus, the established method can be used for the process control in the dimethyl carbonate industrial production with satisfactory results.