(599b) Co-Production of Methanol and Dimethyl Ether Using a Zinc Carbonate Modified Catalyst System

Authors: 
Ye, L., Ohio University
Lee, S., Ohio University
A carbonate modified dual-catalytic system of Cu/ZnCO3/Al2O3 andγ- Al2O3 was successfully devised and developed using the SEAM’s proprietary condensed-phase reactive modification technology. This catalyst system was also experimentally investigated in a fully continuous, proof-of-concept mini-pilot scale system for a process engineering study of single-stage syngas-to-dimethylether (ssDME) process. The preliminary experimental results have revealed that (1) the modified catalyst exhibits a good potential to maintain the initial catalytic activity for a prolonged time in a typical reaction environment; (2) the catalyst exhibits high CO2 tolerance and reactivity for the CO2-rich feed syngas; and (3) the catalyst possesses an enhanced attrition resistance. This study has also shown that 1) supercritical carbon dioxide is a good medium to convert the conventional Cu/ZnO/Al2O3to the modified Cu/ZnCO3/Al2O3; 2) the modified catalyst exhibits a reduced CuO crystallite size, and a larger surface area when compared with the original unmodified catalyst; 3) the ZnCO3 modified catalyst provided a better resistance to mechanical attrition during harsh reactor operation; and 4) the modified catalyst shows substantially enhanced anti-leaching characteristics against both water and slurry medium of high-boiling mineral oil. The current concept of pre-reduction modification of the catalyst enables the modified catalyst to be commercially producible as an added benefit.