CO2-mediated oxidative dehydrogenation of light alkanes to olefins: Advances and perspectives in catalyst design and process improvement

Simultaneous valorization of anthropogenic CO2 and underutilized light alkanes (C2-C4) in shale gas and other feedstock into valuable platform chemicals (olefins) is a highly promising green alternative. The route involves CO2-assisted oxidative dehydrogenation of the feedstock (CO2-ODH) with zero direct H2 input, and can bring about a paradigm shift in the chemical industry towards becoming more environmentally benign. Herein, we reviewed and discussed recent advances in these processes under common themes related to activation mechanism, catalyst development, and process improvement. Notably, we elucidated various catalyst design and tuning strategies that can potentially guide in future design of novel CO2-ODH catalysts with high activity, high olefin selectivity, and long-term stability. The design strategies were illustrated in the light of crucial catalytic features and various nanoscale phenomena such as oxygen mobility, charge transfer, defect creation, interfacial synergy, and balanced acidity that strongly influence and regulate overall catalytic performance. In addition, the review captured a discussion on prospects of dual-function materials for integrated CO2 capture-utilization via CO2-ODH. Moreover, challenges and perspectives have been provided to stimulate further progress in the CO2-ODH processes towards becoming commercially and industrially viable alternatives.