Design of intensified chemical processes for the production of ethyl tert-butyl ether

Abstract

Process intensification contributes to the design of processes with better sustainability performance by allowing several tasks to be performed within the same equipment unit, for instance, reaction and separation. This work aims at the design of intensified processes using a phenomena-based methodology. A gradual intensification approach is used, and each structure is evaluated from economic and environmental considerations. A production process of ethyl tert-butyl ether (ETBE) was selected as a base flowsheet to be intensified. The process consists of one reactor and three conventional distillation columns. Three intensified process alternatives are developed, which employ technologies such as reactive distillation column (RDC), dividing wall column (DWC), and reactive dividing wall column (RDWC). The fully intensified structure, based on a RDWC, showed the best economic indicator with a total annual cost reduction of 26.7% with respect to the base case process; the partially intensified structures showed similar improvements of 18%. The energy savings offered by the intensified flowsheets provide direct benefits from environmental considerations.