Mn基LDOs@TiO2低温脱硝材料的构筑及其强化N2选择性与抗硫稳定性机制研究

低温选择性催化还原技术（LT-SCR）是高效去除NOx的重要发展方向，然而低温Mn基脱硝催化剂仍存在热稳定性差、N2选择性低、长期运行下抗硫稳定性不足等亟待解决的问题。本项目利用类水滑石衍生氧化物（LDOs）材料独特的优势，制备结构/性质可调控的核壳结构型Mn基LDOs@TiO2复合材料。Mn基LDOs材料结构的可调控性、金属组分的高分散等特性，可作为高效稳定的核层材料，在此基础上，筛选气体扩散阻力小以及与SO2吸附力较弱的TiO2壳层材料，构筑低温催化活性高、N2选择性高、活性温度窗口宽且长期运行抗硫稳定性能优异的新型低温脱硝催化剂。探究材料的理化特性对脱硝性能和抗硫性能、机理的影响，揭示构-效-理关系。结合DFT理论计算，从分子水平阐释反应物和中毒影响因素在复合材料上的活性位点、中间产物、催化机理及抑制机制，为设计高效SCR脱硝工艺及其产业化提供理论基础和技术支撑。

Low-temperature selective catalytic reduction technology (LT-SCR) is emerging important development direction for high-efficiency removal of NOx. However, low-temperature Mn-based denitration catalysts still have the problems of poor thermal stability, low N2 selectivity, and insufficient sulfur resistance stability under long-term operation. This project utilizes the unique advantages of layered double oxides (LDOs) materials to prepare core-shell structured Mn-based LDOs@TiO2 composite materials with adjustable structure/properties. The controllability of the structure of Mn-based LDOs and the high dispersion of metal components can be used as an efficient and stable core material. And TiO2 material with low gas diffusion resistance and weak SO2 adsorption are screened as shell material. This project intends to construct a novel LT-SCR catalyst with high catalytic activity, high N2 selectivity, wide active temperature window and excellent sulfur resistance stability. The influence of the physical and chemical properties on the denitration and sulfur resistance performance and mechanism are explored to reveal the structure-activity-physical relationship. Combining DFT theoretical calculations to analyze the active sites, intermediate products, catalytic reaction pathways and inhibition mechanisms of reactive species and influencing factors on composite materials from the molecular level. The project will provide theoretical basis and technical support for the design of high-efficiency SCR denitration process and its industrialization.