Advances in the studies of CO2-assisted oxidation dehydrogenation of light alkanes over metal-based heterogeneous catalysts

The CO₂-assisted dehydrogenation of light alkanes not only enables the production of basic chemicals like light olefins but also promotes the resource utilization of CO₂, co-producing feedstocks such as CO and H₂. In the context of the "dual carbon" goals, developing this technology and its catalysts is crucial for optimizing energy structures and fostering the sustainable development of the petroleum and chemical industries.

Significant progress has been achieved in catalytic technologies for CO₂-assisted oxidative dehydrogenation of light alkanes in recent years. Various metal-based catalysts exhibit different catalytic performances due to their unique properties. This review summarizes the catalytic performance of different metal-based catalysts in CO₂-assisted oxidative dehydrogenation of light alkanes, along with common elements involved in the reported active components and supports. The active components range from noble metals to transition metals and metal oxides, as well as single metals to bimetallic, and high-entropy alloy systems.

For different types of catalysts, CO₂ plays distinct roles in the dehydrogenation of light alkanes, summarized as follows: (1) Consuming the hydrogen species derived from dehydrogenation reaction via reverse water-gas-shift reaction that shifts the equilibrium of dehydrogenation reaction; (2) Replenishing active oxygen species consumed by oxidative dehydrogenation reaction to refill oxygen vacancies based on the Mars-van Krevelen mechanism; (3) Eliminating coke deposits on the surface of active metal sites through the reverse Boudouard reaction, thereby regenerating active sites; (4) Oxidizing the reduced metal sites that facilitates the cleavage of C-C bonds to suppress side reactions.

This review published by prof. Xiangxue Zhu and prof. Xiujie Li from Dalian Institute of Chemical Physics, Chinese Academy of Sciences, summarizes the catalytic performance of various metal-based catalysts in the CO₂-assisted oxidative dehydrogenation of light alkanes, with the goal of identifying catalyst systems that hold great potential for further development. Exploring the role of CO₂ in alkane dehydrogenation aims to elucidate the mechanisms of CO₂ activation and transformation. Analyzing the types of active sites, their chemical valence states, coordination environments, as well as the functional roles of additives and supports, the goal is to develop bifunctional or multifunctional composite catalysts of synergistically activating C=O and C-H bonds. The precise construction of multifunctional sites, in situ analysis of the kinetic behavior of active sites, and diversified development of catalytic systems will be crucial for achieving breakthroughs in CO₂-assisted dehydrogenation of light alkanes with heterogeneous metal catalysts. The review was published in the Chinese Journal of Catalysis (https://doi.org/10.1016/S1872-2067(24)60094-X).

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About the Journal

Chinese Journal of Catalysis is co-sponsored by Dalian Institute of Chemical Physics, Chinese Academy of Sciences and Chinese Chemical Society, and it is currently published by Elsevier group. This monthly journal publishes in English timely contributions of original and rigorously reviewed manuscripts covering all areas of catalysis. The journal publishes Reviews, Accounts, Communications, Articles, Highlights, Perspectives, and Viewpoints of highly scientific values that help understanding and defining of new concepts in both fundamental issues and practical applications of catalysis. Chinese Journal of Catalysis ranks among the top one journals in Applied Chemistry with a current SCI impact factor of 15.7. The Editors-in-Chief are Profs. Can Li and Tao Zhang.

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