Production of a green multi-purpose fuel by reactive distillation

Dimethyl ether (DME) is receiving growing attention as a promising alternative and multipurpose green fuel. World production today is primarily by means of methanol dehydration using solid acid catalysts in a fixed bed reactor followed by ordinary distillation columns. In this study, the continuous production via a single reactive distillation (RD) column is studied experimentally in a pilot-scale plant. Kinetics of liquid dehydration of methanol over the sulphonic resin Amberlyst 35 is also studied, using both a batch reactor and a tubular fixed-bed reactor in a temperature range of 100-140°C and a pressure up to 50 bar. The experimental kinetic data are described well by the Eley-Rideal mechanism, and the kinetic parameters are incorporated into a rate-based RD model implemented in the simulation environment Aspen Custom Modeler® (ACM®). The pilot-scale RD experimental results support the feasibility and benefits of the DME synthesis by RD process and are used to validate the predictive RD model. The validated model can be used for future sensitivity analyses and process optimization studies as well as benchmarking compared to the state of the art technology.