Recent progress in Cr-based catalysts for oxidative dehydrogenation of light alkanes by employing CO_(2) as a soft oxidant

CO_(2) can be used as a soft oxidant for oxidative dehydrogenation of light alkanes(CO_(2)-ODH),which is beneficial to realize the reuse of CO_(2) and meet the demand for olefins.The core of this reaction is the catalyst.Cr-based catalysts have attracted much attention for their excellent catalytic performance in CO_(2)-ODH reactions due to their various oxidation states and local electronic structures.In this paper,the synthesis and modification methods of Cr-based catalysts for CO_(2)-ODH are reviewed.The structure-activity relationship and reaction mechanism are also summarized.Moreover,the reasons for the deactivation of Cr-based catalysts are analysed and the main challenges faced by Cr-based catalysts in the CO_(2)-ODH process,as well as the future development trend and prospect,are discussed.