A Hybrid Process Combining Reactive Distillation and Pervaporation Membrane for Dimethyl Ether Production from Crude Glycerol

Abstract

In this work, the hybrid process employing a single reactive distillation with a pervaporation membrane is introduced for enhanced dimethyl ether (DME) production from the conventional process. The conventional process implemented a single reactive distillation and a recovery column to produce DME from crude glycerol. The key problem of the process, when glycerol is involved, is the low operating pressure condition required in the recovery column due to the limitation of glycerol at high temperature. This condition means high cost and energy requirement in the process. To solve the problem, a cellophane membrane as a pervaporation unit is proposed to replace the recovery column that is used in the conventional process for separating glycerol/water mixture. The optimal simulation design for the hybrid process was determined in terms of the minimization of total annual cost (TAC). The simulation results revealed that the hybrid process combining the reactive distillation and the pervaporation membrane has a lower cost up to 30% compared to the conventional process. By implementing the pervaporation unit, the low operating pressure condition can be avoided. Moreover, due to the availability of the commercial cellophane membrane, this hybrid process can be implemented in the real industry.

Keywords: Reactive Distillation; Pervaporation; Energy Efficiency; Economic Savings; Hybrid Process