Effect of Operating Conditions on Dimethyl Ether Steam Reforming in a Fluidized Bed Reactor with a CuO–ZnO–Al2O3 and Desilicated ZSM-5 Zeolite Bifunctional Catalyst

Abstract

This paper studies the effect of operating conditions in dimethyl ether (DME) steam reforming on a bifunctional catalyst synthesized with CuO–ZnO–Al2O3 metallic function and a HZSM-5 zeolite treated with NaOH to moderate acidity. The experimentation has been carried out in a fluidized bed reactor in the 225–325 °C range, with space time between 0.1 and 2.2 gcatalyst h/gDME, steam/DME molar ratio between 3 and 6, and DME partial pressure between 0.08 and 0.25 bar. The 275–300 °C range is suitable for obtaining high values of DME conversion and H2 yield with minimum CO formation and deactivation by coke and avoiding hydrocarbon formation. Stable values of DME conversion (0.85), H2 yield (0.81), and H2 production rate (180 mmolH2/(gcatalyst h)) are obtained during 48 h at 300 °C with a steam/DME ratio of 4 and space time of 0.60 gcatalyst h/gDME. The main cause of deactivation is coke deposition on the metallic function.