用于1,2-二氯乙烷催化氧化反应的Ru-LaMnO3催化剂的制备及其协同作用机制的研究

Catalytic oxidation technology has been extensively applied for the abatement of chlorinated volatile organic compounds because of its advantages such as low energy consumption, high efficiency and free of pollution. LaMnO3 perovskite oxide owning low cost and excellent redox ability has broad applications in this field. Currently, rapid deactivation and polychlorinated byproducts formation induced by chlorine deposition on catalysts surface remain to be resolved urgently. This project will employ Ru modification strategy to efficiently eliminate surface chlorine species via Deacon Reaction catalyzed by Ru active species, and thus improve the catalytic stability and desired products selectivities for the catalytic oxidation of 1,2-dichloroethane. The correlationship between the physicochemical properties and catalytic performances over Ru-LaMnO3 catalysts will be elucidated. The effect of the interaction between Ru and LaMnO3 on the catalytic reaction will be eventually determined after modifying the surface properties of Ru domains on LaMnO3 oxide and analyzing the reaction pathways of chlorine dissociation, migration and desorption processes. The determination of active sites for key catalytic reaction pathways and the clarification of synergistic mechanism on Ru, Mn active species will be achieved after exploring the similarities and differences of catalytic reaction pathways on single or dual active species with the combination of catalysts characterizations at different reaction stages. This project is aiming at providing fundamental knowledge for developing novel metal oxide catalytic materials and improving catalytic performances of catalysts.

催化氧化技术因其能耗低、高效、环保等优势被广泛应用于含氯挥发性有机化合物的净化处理。LaMnO3钙钛矿氧化物价格低廉且具备优异的氧化还原能力，在该领域具有广阔的应用前景。然而因氯物种富集导致的催化剂失活及多氯副产物产生仍是目前研究中亟需解决的难题。本项目拟采用Ru修饰手段，通过Deacon反应有效脱除表面的氯物种，提高催化剂催化氧化1,2-二氯乙烷的反应稳定性和目标产物选择性, 并探明催化剂的物化性质与催化反应性能的关联规律；通过Ru在LaMnO3氧化物上负载状态的调控，研究氯解离、迁移及脱除过程的反应路径，明确Ru与LaMnO3间相互作用对催化反应的影响效应；通过单一及双活性物种上的催化反应路径分析，并结合不同反应阶段的催化剂物化表征，确定关键催化反应路径的活性中心，揭示Ru、Mn活性物种间的协同作用机制。该项目为开发新型的金属氧化物催化材料、提升催化剂的反应性能提供重要的理论研究基础。

低温催化氧化技术因操作温度低、净化效率高、无二次污染等优势被广泛应用于工业挥发性有机污染物净化。作为该技术的核心和关键要素，设计和开发低成本、高催化活性和稳定性的催化材料一直是这一领域的研究热点。本项目从金属氧化物的改性和金属-载体间相互作用的强化角度出发，采用酸处理、过渡金属掺杂、载体形貌控制、尺寸和结构调控等策略制备了Co3O4、LaMnO3金属氧化物以及RuCoOx/Al2O3、MnOx/HZSM-5负载型催化剂用于甲苯、丙烷、氯乙烯等典型挥发性有机污染物的低温催化氧化反应。重点研究了酸处理浓度、Ni掺杂量、Al2O3形貌以及HZSM-5分子筛的尺寸和结构对催化氧化反应性能的影响效应，确定了催化材料物理化学性质和催化性能间的关联规律；通过多种原位表征和动力学手段对气相反应物分子在催化剂表面的吸附、活化、氧化行为和转化路径进行研究，揭示了不同催化体系下挥发性有机物表面催化过程的反应机理。本项目的开展为开发新型的催化氧化材料、提升其反应性能并促进其在工业有机废气净化领域的产业化应用提供重要的研究基础。