High carbon utilization for CO2 conversion with chloromethane to aromatics over acidic zeolite catalyst

Carbon dioxide (CO2) and methane (CH4) are major greenhouse gases, and the use of these C1 resources to produce high-value chemicals is significant for sustainable chemistry. Due to the high stability and C-C coupling barriers, simultaneous conversion of CO2 and CH4 to aromatics remains challenging. Herein, we report a sustainable strategy for utilizing greenhouse gases based on the conversion of CO2 and CH3Cl, an alternative of CH4, that yields a high aromatics selectivity (71.3%) with -50% BTX selectivity using H-ZSM-5 as catalyst at 723 K and 3 MPa. In situ characterization and 13C isotope-labeling experiments demonstrate that CO2 directly participates in the formation of aromatics via lactone species instead of undergoing a classical reverse water-gas shift reaction. Furthermore, a unique mechanism for CO2 conversion is proposed, involving the formation and subsequent transformation of lactone and cyclopentenone species. This work expands high carbon utilization pathways for converting greenhouse gases into chemicals.