Prototype Catalytic Membrane Reactor for Dimethyl Ether Synthesis via CO<sub>2</sub> Hydrogenation
Qiaobei Dong, Weiwei Xu, Xiao Fan, Huazheng Li, Naomi B. Klinghoffer, Travis Pyrzynski, Howard Meyer, Xinhua Liang, Miao Yu, Shiguang Li
Abstract
Dimethyl ether (DME) has become attractive as a potential environmentally friendly substitute for diesel and liquefied petroleum gas (LPG) due to its similar properties to those of LPG, high cetane number, but less carbon emissions. In this work, we developed a novel prototype-scale catalytic membrane reactor to synthesize DME directly from CO2 and renewable H2, which could address the environmental and fuel security issues in a cost-effective way. This membrane reactor was equipped with superior hydrophilic NaA zeolite membranes and bifunctional Cu–ZnO–ZrO2–Al2O3/HZSM-5 catalysts. The effects of the reaction temperature and gas hourly space velocity (GHSV) on the DME synthesis were investigated. Compared with the fixed bed catalytic reactor, the catalytic membrane reactor with a unique NaA membrane significantly enhanced the DME yield and CO2 conversion from 8.71 and 21.4 to 22.8 and 33.7%, respectively. The highest DME production rate of 1.31 kg/day was achieved at 300 °C and a GHSV of 8400 mL/(g·h). This work demonstrates the feasibility of the catalytic membrane reactor for DME production via CO2 hydrogenation as an approach to market readiness.