SO2与NO在新型核壳材料上的分层同时吸附及其构效关系研究

For the purpose of the integrated control of a variety of air pollutants, the research on simultaneous removal of SO2 and NO emission from coal-fired flue gas are of great significance. However, due to the adsorption competitive of SO2 and NO, the NO adsorption removal efficiency is limited by the traditional materials during simultaneously desulfurization and denitrification. Therefore, in order to achieve high efficiency of simultaneously desulfurization and denitrification in flue gas, it is necessary to develop a new adsorbent material. According to the different physical and chemical properties of SO2 and NO in coal-fired flue gas, a new-type adsorbent of core-shell structure materials will be designed and developed via the adsorbent molecular structure to achieve the simultaneous removal of SO2, NO in this project, and the removal efficiency of SO2 and NO reach 90% and 60% respectively. The project intends to study the effective shell-forming methods and mechanisms of different core materials and the impact on the adsorption performance of different core-shell material surface physical and chemical property, structure, constitution and distribution of active components. This work will also investigate the influence law on the adsorption process of the flue gas temperature, humidity, oxygen content and flue gas flow. Furthermore, the interaction and the physical and chemical effect between the denitrification reaction on the core surface and desulfurization reaction on the shell surface will be achieved. This project will provide a new theoretical basis and method for efficiently and simultaneously desulfurization and denitrification from the coal-fired flue gas.

基于多种大气污染物综合控制的目的，研究燃煤烟气中SO2和NO的同时吸附脱除意义重大，但由于SO2和NO存在吸附竞争，采用传统材料同时脱除时，NO的去除效果有限。因此，为实现烟气的高效同时脱硫脱硝，开发新型吸附材料十分必要。本项目拟通过实验和计算模拟相结合，根据SO2和NO不同的理化性质，从吸附剂分子结构层面着眼设计，研发新型核壳结构吸附剂，使其具有相对独立、互不干扰的分别适用于SO2和NO分子吸附的活性位，实现烟气中SO2、NO的同时脱除，脱除效率分别达到90%和60%。项目拟系统研究不同核体材料的有效成壳方法及其作用机制，不同核壳材料表面物化特性、结构、有效组分构成、活性物质分布等对同时脱硫脱硝的影响，获得烟气温度、湿度、含氧量、烟气量等对吸附过程的影响规律；深入研究核表面的脱硝反应与壳表面的脱硫反应之间的相互影响和理化作用等本质科学问题，为烟气同时高效脱硫脱硝技术提供新思路和理论依据。

多污染物的协同去除是当今环境领域研究的热点。本项目针对SO2和NO同时吸附去除时存在竞争吸附问题，在前期工作的基础上，根据两种气体的化学特性，筛选了核、壳材料，采用不同设计理念设计并制备了多种核壳结构吸附剂，研究了合成条件及吸附过程影响因素对SO2和NO吸附行为的影响，并探讨了SO2、NO在核壳材料上同时吸附脱除机理研究。通过核、壳材料的表面改性，调控吸附剂的物理化学性能，从而进一步提高吸附剂的同时脱硫脱硝性能。本项目测定了多种常见吸附剂（MnOx、TiO2、Al2O3、SiO2、分子筛等）同时脱硫脱硝性能，筛选出适宜得核、壳材料，得到最佳制备条件。制备得到具有较好同时脱硫脱硝性能的Ni/Fe类水滑石吸附剂及Fe3O4-TiO2复合吸附剂，以及根据不同设计理念合成了SiO2-MnOx、SAPO-34@Al2O3、Al2O3@TiO2、MgO@OC、MgO@CeO2-MnOx核壳结构吸附剂，实现了对SO2和NO的同时高效去除，通过改性进一步提高了Al2O3@TiO2核壳结构吸附剂的同时脱硫脱硝性能，并通过相关表征及动力学计算，对吸附剂同时脱硫脱硝机理进行了探讨。相关研究成果，发表论文12篇，其中SCI检索论文10篇，核心论文2篇，申请发明专利两项（均已公开），培养硕士生4名，博士生1名。本项研究为环境治理及多污染物协同去除提供了科学依据，为吸附剂的设计与制备提供了新的思路，对大气污染控制具有十分重要的意义。