PEP Review 79-2-1
Ethylene Glycol via Ethylene Carbonate
Published: March 1980
There has been recent patent activity with respect to a process whereby ethylene oxide is converted to ethylene glycol by reaction with CO2 to form ethylene carbonate, which is in turn hydrolyzed to glycol. We first evaluated this carbonation process in PEP Report No. 70; a new process design and estimate are presented herein, and the economics are compared with those of the conventional ethylene oxide hydration route to glycol.
The carbonation process provides a saving in production cost. This is largely because of a much lower steam requirement, owing to there being less excess water to remove from the glycol. The carbonate process produces smaller amounts of di- and triglycol coproducts, but the smaller requirement of ethylene oxide largely counterbalances the loss in credits.