A Novel, Low Temperature Synthesis Method of Dimethyl Ether Over Cu–Zn Catalyst Based on Self-Catalysis Effect of Methanol

摘要

A new DME synthesis route from syngas at a relatively low temperature (443 K) has been developed for the first time by the combination of a conventional DME synthesis catalyst (Cu/ZnO:HZSM-5 catalyst) with methanol as a catalytic solvent. The addition of methanol to the reaction system is the key to the success of DME synthesis at this temperature. Indeed, a CO conversion of 29 and 43% with a DME selectivity of 69 and 68% were achieved at 443 or 453 K, respectively, and 4 MPa, when methanol was used as a catalytic solvent. Importantly, no other by-products including methanol and hydrocarbons were observed in the DME product attained, suggesting no significant subsequent purification stages. Assuming no scale up problems, this process potentially provides a high purity of DME with less energy consumption, and so offers an opportunity for the economically viable future sustainable production of DME.