Co-production of dimethyl ether and methanol from CO2 hydrogenation:: development of a stable hybrid catalyst

Efforts have been made aimed at the development of an active active and stable catalyst in the co-production of dimethyl ether (DME) and methanol from CO2-H-2. The stabilities of ZSM-5 catalysts and Cu-ZnO-based methanol synthesis catalysts were investigated separately under water-rich conditions, By combining each stable catalyst, a relatively stable hybrid catalyst, Cu-ZnO-Al2O3-Cr2O3 + H-ZSM-5 (SiO2/Al2O3=80), has been developed. After losing about 5% of its original activity in 120 h, the catalyst exhibited no significant reduction in activity until 350 h in the reaction at 523 K and 3.0 MPa. Also, the catalytic activity was satisfactory at the steady state: the total yield of DME and methanol was higher than 26% with over 90% DME selectivity, but the total yield of hydrocarbons was lower than 0.25%. Copyright (C) 2001 John Wiley & Sons, Ltd.