Novel Ethylene Oxide Gas Recovery System via Hydrolysis in the Dimethyl Carbonate and Monoethylene Glycol Production Process

Dimethyl carbonate (DMC) and monoethylene glycol (MEG) have numerous potential applications in addition to their current uses. DMC and MEG are produced by the transesterification reaction of ethylene carbonate (EC) and methanol (MeOH), while EC is synthesized by reacting ethylene oxide (EO) and carbon dioxide (CO₂). The vent gas generated when EC is recovered from a flash drum contains both EO and EC. EO gas is hazardous and highly explosive, and the vent gas is therefore fed to a scrubber. The use of conventional scrubbers, however, results in issues such as the production of wastewater, the use of large quantities of water, and the loss of valuable substances. Therefore, this study proposes a novel system of converting EO and EC in vent gas into MEG. This new recovery system does not generate wastewater and produces an additional 245 tons of MEG per year, thereby increasing the potential profits of this system in comparison to conventional scrubbers. In addition, the effects of major variables on the new recovery system were analyzed to provide a guide for designing and operating such a system. Additionally, this study aids in determining the most profitable gas treatment process when designing a factory that manufactures MEG from EC.