CO2-assisted oxidation dehydrogenation of light alkanes over metal-based heterogeneous catalysts

Light olefins are important platform feedstocks in the petrochemical industry, and the ongoing global economic development has driven sustained growth in demand for these compounds. The dehydrogenation of alkanes, derived from shale gas, serves as an alternative olefins production route. Concurrently, the target of realizing carbon neutrality promotes the comprehensive utilization of greenhouse gas. The integrated process of light alkanes dehydrogenation and carbon dioxide reduction (CO₂-ODH) can produce light olefins and realize resource utilization of CO₂, which has gained wide popularity. With the introduction of CO₂, coke deposition and metal reduction encountered in alkanes dehydrogenation reactions can be effectively suppressed. CO₂-assisted alkanes dehydrogenation can also reduce the risk of potential explosion hazard associated with O₂-oxidative dehydrogenation reactions. Recent investigations into various metal-based catalysts including mono- and bi-metallic alloys and oxides have displayed promising performances due to their unique properties. This paper provides the comprehensive review and critical analysis of advancements in the CO₂-assisted oxidative dehydrogenation of light alkanes (C2-C4) on metal-based catalysts developed in recent years. Moreover, it offers a comparative summary of the structural properties, catalytic activities, and reaction mechanisms over various active sites, providing valuable insights for the future design of dehydrogenation catalysts.