(572a) Energy-Efficient Design of Direct Diethyl Carbonate Production from Ethyl Carbonate and Ethanol

In this study, two novel process for producing diethyl carbonate (DEC) and ethylene glycol by transesterification was presented. Dimethyl carbonate (DMC), which is the feedstock for DEC production, requires additional distillation techniques (e.g. pressure swing distillation, extractive distillation) due to the formation of azeotrope between methanol. To deal with this issue, this research combines the production process of DMC and DEC through reactive distillation without separating azeotrope. Two design alternatives based on the catalyst type and process configuration were proposed. In the first alternative, utilizing two reactive distillation column and one separation column, azeotrope was circumvented by the transesterification reaction between ethanol and DMC. This approach reduces equipment needs, resulting in a 12% decrease in total utility usage and annual costs compared to the current method. The second design consolidates all transesterification reactions within a single reactive distillation column, leading to a 24% cut in overall utility consumption and a 14% reduction in total annual cost. These design alternatives both show improved economic viability and also curtailed carbon dioxide mitigation by 15% and 11%, respectively.