Comparison of direct and CO2-oxidative dehydrogenation of propane

Propane dehydrogenation to propylene has received increasing attention due to the fast growth in propylene demand and the exploration of shale gas containing propane. Direct dehydrogenation of propane (DDHP) offers high propylene selectivity but is limited by quick deactivation due to coke formation. CO2-assisted oxidative dehydrogenation of propane (CO2-ODHP) can consume CO2 and meanwhile reduce coke deposition via the reverse Boudouard reaction. In the current review, direct and CO2-assisted dehydrogenation of propane has been compared from three aspects: reaction mechanisms, catalyst compositions, and CO2 footprint analysis. As the average CO2 emissions from electricity generation decrease due to the utilization of renewable energy, CO2-ODHP potentially leads to a net-negative CO2 footprint while DDHP cannot.