Highly Active Cu-CeZrO_x/ZSM-5@Si Catalyst for Direct Conversion of Syngas to Aromatics

Syngas (CO/H₂) is generally considered to be a non-petroleum carbon resource for production of liquid fuels and chemicals. Among routes of syngas conversion, the alternative to Fischer–Tropsch is a one-pass process converting syngas into value-added aromatics over metal oxides/zeolites (OX-ZEO). However, achieving high activity and high aromatics selectivity on the OX-ZEO catalysts remains a challenge. Impregnation of an appropriate amount of highly dispersed copper on CeZrO_x can significantly improve CO conversion and selectivity to light aromatics. The characterizations and catalytic performance evaluations revealed that appropriate impregnation of copper on CeZrO_x improves the H₂ activation ability as well as effectively increases oxygen vacancy concentration. The synergistic effect of more active H and oxygen vacancy results in forming abundant oxygenated intermediate species. Furthermore, the optimal catalyst 1/200Cu-CeZrO_x/ZSM-5@Si still maintains 35% CO conversion and 84% aromatics selectivity after 100 h of reaction.