Effect of supercritical fluid of CO_2 drying during Cu/ZnO catalyst preparation on methanol synthesis from syngas at low temperature

摘要

A copper-based catalyst can be utilized to synthesize methanol from syngas containing carbon dioxide as well as water at low temperature and low pressure. However, the agglomeration of the metallic copper and zinc oxide decreased the catalyst surface area and the Cu-specific surface area. In order to prevent the sintering, the supercritical CO_2 was used to extract water from the catalyst precursor. Our results demonstrate that the Cu-specific surface area was the essential factor to affect the catalytic activity. A larger Cu-specific surface area would cause higher methanol synthesis activity. The optimized supercritical CO_2 drying condition was at 308 K and 8.0 MPa for 3 h when the methanol yield reached 44.8%.