Probing synergistic effect of active Cu0 species and surface acidity of chainlike ZSM-5 supported copper catalysts in methanol dehydrogenation to methyl formate

A series of chainlike ZSM-5 supported Cu catalysts with the addition of citric acid (CA) was conveniently prepared using a complexation-impregnation method and employed in the methanol dehydrogenation to methyl formate (MF). The catalytic performance of Cu x /CZ5 first increased and then decreased with increasing CA/Cu ratio, reached 35.0% methanol conversion and 88.3% MF selectivity for Cu1.8/CZ5, significantly higher than that of Cu/CZ5. The superior catalytic performance might be principally explained by the higher Cu 0 concentration combined with abundant Brønsted acid sites, which are responsible for methanol conversion and MF selectivity, respectively. This work provides new insights into the synergy between Cu 0 species and surface acidity of Cu x /CZ5 catalysts for methanol dehydrogenation and offers a feasible and effective strategy for enhancement of the catalytic performance of copper-based catalysts.