铁催化剂二氧化碳加氢制烯烃反应机制及反应动力学研究

CO₂高效转化与高值化利用是世界科技热点研究方向，也是国家重大技术需求。铁基催化剂CO₂加氢合成低碳烯烃是实现CO₂转化与高值利用的最佳途径之一。如何通过创新催化剂结构设计，提高目标产品的选择性和产率仍然是该领域的巨大挑战。由于反应体系复杂及研究技术局限，研究者对于催化剂表界面动态结构演变规律及反应机理认知仍然不足，制约着高效催化剂结构设计及工业反应器开发。本项目聚焦铁基催化剂CO₂催化加氢的本征反应动力学、反应机理和铁基催化剂动态结构演化。拟建立CO₂加氢的反应网络、关键速控步骤及本征动力学模型，明晰含碳产物的分布规律；解析反应条件下铁基催化剂结构及其随反应外场变化的演变规律；揭示铁基催化剂结构对CO₂加氢活化和含碳产物生成的反应机理与反应动力学的作用机制。项目顺利实施可为调控高效铁基催化剂活性结构、设计工业催化反应器以调控低碳烯烃的选择性和产率提供理论支撑。

Attempts to utilize and convert CO₂ to high-value products have remained the subject of intense research, and also are the requirement in technological for our state. Hydrogenation of CO₂ over Fe catalysts to synthesize olefins is one of the optimization pathways for the conversion and utilization of CO₂. However, improving the selectivity and yield of target product by innovatively designing the structure of catalyst is still a largely unresolved challenge. This is caused, in large part, by challenge in the complex reaction network and the limitation of research techniques, therefore the dynamic transitions in both bulk and surface of catalyst and the reaction mechanism have not been unambiguously established, and thus restrict the design of the structure of catalyst with high activities and the development of the industrial reactor. In this project, we will probe the intrinsic reaction kinetics, reaction mechanism and the dynamic transition of catalyst during hydrogenation of CO₂ over Fe catalysts, identify the reaction network, kinetically relevant steps and mechanistic kinetic equations at molecular level for hydrogenation of CO₂ and reveal the distributions of carbon containing products, explore the catalytic consequences of the structure of Fe catalysts on the reaction mechanism and kinetics of the activation of CO₂ and the formation of carbon containing products from hydrogenation of CO₂. Successfully completing the proposed project can provide theoretical foundations and strategies for tuning the selectivities and yields of olefins in industrial plants by tuning the structure of Fe catalyst and the industrial catalytic reactor.