Feasibility study and process design of a direct route from bioethanol to ethylene oxide

A novel route for the direct one-pot oxidation of ethanol to ethylene oxide has been designed and scaled-up into a full process: this is the very first design of an innovative one-step conversion route from bioethanol to ethylene oxide. Starting from the review and interpolation of reaction kinetics, a staged, cooled reactor is sized for the air-based oxidation of bioethanol, yielding ethylene oxide in one-step. An efficient strategy for the separation of the product from the gas phase effluent of the reactor is developed, based on absorption in a hydro-alcoholic solution rather than in pure water. This in turn brings a material recycle between the feed and purification section that benefits the atom economy. As the basis of an economic analysis, the energy balances are assessed and analyzed via the Pinch Analysis method. The calculations let foresee a conversion of 90% of bioethanol into Ethylene Oxide (> 99% purity) and 7.7% into marketable ethylene-glycol.