CH4-CO2重整新型高抗积炭碳化钼催化剂的设计、性能与催化机理研究

The reforming reaction turns two greenhouse gases (CH4 and CO2) into synthesis gas, which is one of the best route for greenhouse gas emission reduction and utillization. The key to the industrialization of CH4-CO2 reforming is developing a cheaper catalyst system with high activity and high coke-resistance. Based on the high coke-resistance performances of noble metal and transition-metal carbide catalysts, we firstly prepared noble metal/Mo carbide composite catalysts with ultra low content (≤0.1 wt.%)of noble metal for CH4-CO2 reforming. The deactivation of Mo carbide is due to CO2-induced oxidation on Mo carbide surface. This problem can be resolved from the following ways: by promoting CH4 activation by noble metals, by adjusting crystal lattice stability of Mo carbide through controlling the morphology and by using the interaction between noble metal and Mo carbide. Therefore, we can obtain a highly efficient and stable CH4-CO2 reforming catalyst system. The microstructure and surface properties of the composite catalysts are associated with their catalytic activities to reveal the interactions between carbides and noble metals and their similarities in chemical properties, which can provide a theoretical basis for developing transition-metal carbides as new catalytic materials to replace or partially replace noble metals. Additionally, the feasible approach to the stabilization of carbide crystal lattice and lattice carbon transfer rules can be obtained to provide a basis for designing and developing carbides as new highly efficient catalysts.

两种主要温室气体CH4和CO2重整制合成气是温室气体减排和利用的最佳技术路线之一。研发高活性、高抗积炭性且廉价易得的催化剂体系是该重整反应工业化的关键。本项目利用贵金属和过渡金属碳化物这两类重整催化剂的高抗积炭性能，首次构建CH4-CO2重整新型超低量（≤0.1 wt.%）贵金属/碳化钼复合催化剂。通过贵金属促进CH4活化、碳化钼形貌控制调控晶格稳定性以及利用贵金属与碳化钼之间的相互作用，解决碳化钼因CO2深度氧化导致失活的技术难点，实现CH4-CO2重整催化剂的高效和稳定。通过研究该复合催化剂微观结构和表面性质与催化性能之间的关联，揭示碳化物与贵金属具有相似化学性质及相互作用的微观本质，为碳化物作为新型催化材料替代或部分替代贵金属提供理论依据。同时，本项目所获得的碳化物晶格稳定化的可行途径和晶格碳迁移规律将为碳化物作为新型高效催化剂的设计和研发提供基础。

两种主要温室气体CH4 和CO2 重整制合成气是温室气体减排和利用的最佳技术路线之一。研发高活性、高抗积炭性且廉价易得的催化剂体系是该重整反应工业化的关键。本项目利用过渡金属碳(磷)化物与贵金属具有相似的催化性质，将其应用到CH4-CO2 重整反应。通过碳纳米管与碳化钼之间的相互作用，促进碳化钼氧化碳化循环，解决碳化钼因CO2 深度氧化导致失活的技术难点，实现CH4-CO2 重整催化剂的高效和稳定。通过研究该复合催化剂微观结构和表面性质与催化性能之间的关联，揭示碳化物与贵金属具有相似化学性质及相互作用的微观本质，为碳化物作为新型催化材料替代或部分替代贵金属提供理论依据。另外，研发了新型磷化钼重整催化剂，该催化剂比碳化钼催化剂具有更好的稳定性。本项目所获得的过渡金属碳（磷）化物晶格碳（磷）迁移规律将为他们作为新型高效催化剂的设计和研发提供基础。