低温碳基催化剂协同控制NOx和CVOCs的机理研究

A large amount of nitrogen oxide (NOx) and highly poisonous chlorine volatile organic compounds (CVOCs) exists in waste incineration flue gas containing. However, the general garbage incineration flue gas temperature is lower, and contains a large amount of SO2 and alkali metal fly ash, existing mature technology of flue gas denitration or CVOCs control is difficult to direct application. The design and poisoning mechanism research of bifunctional catalysts at low temperature is seldom in DeNOx and CVOCs removal. We put forward the idea of denitration collaborative CVOCs removal at low temperature, and solve the scientific problem: one is to reveal the catalytic removal of two kinds of pollutants synergy or inhibition mechanism; the second is to make clear the characteristics of flue gas pollutants poisoning mechanism and the thoughts of improve poisoning resistance. This proposal intends to use the transition metals such as vanadium, iron modified activated carbon preparation of new type low temperature denitration and CVOCs removal catalyst, regulating redox site and acid site distribution on surface of catalyst by dope rare earth element such as cerium, optimize proportion and method of dope rare earth element to improve performance of the denitration collaborative CVOCs removal at low temperature; to reveal the mechanism of SO2 and alkali metal poisoning of catalyst using ammonia probe. The expected results are to provide theoretical guidance of controlling of NOx and CVOCs emission simultaneously.

我国垃圾焚烧烟气中含有大量的氮氧化物（NOx）和剧毒的含氯挥发性有机物（CVOCs）等大气污染物。一般垃圾焚烧烟气温度较低，且含有SO2、HCl和碱金属飞灰等，现有烟气脱硝或脱CVOCs控制技术难以应用。本申请书拟设计研发低温双功能催化体系，探索低温协同催化还原NOx和氧化CVOCs的途径。本项目拟采用钒、铁等过渡金属改性活性炭制备新型低温脱硝脱CVOCs（氯苯等）催化剂，通过掺杂铈等稀土元素助剂调控催化剂表面氧化还原位和酸性位分布，优化掺杂助剂比例和方法提高低温协同脱硝脱CVOCs（氯苯等）性能，揭示催化脱除两种污染物的协同或抑制作用机理；利用氨气探针分子揭示催化剂的SO2和碱金属中毒过程，从分子原子水平上明确烟气特征污染物的中毒机制，进一步指导抗中毒催化剂的设计和再生，为实现高效协同脱除NOx和CVOCs提供理论依据。

针对垃圾焚烧烟气中含有的大量NOx及剧毒的含氯挥发性有机物CVOCs等污染物的协同净化，设计开发高表面活性炭负载过渡金属（V、Fe）及稀土元素活性组分和助剂的催化体系，研究新型碳基催化剂低温SCR催化还原NOx协同CVOCs（氯苯等）氧化脱除作用机制及污染物协同净化过程中复杂反应的各种促进和抑制作用机理。结合催化剂分析表征，揭示NOx催化还原活性位和CVOCs吸附及氧化活性位，获得优化的双功能SCR催化剂配方，并从原子水平上考察垃圾焚烧烟气中特征污染物SO2及碱金属元素对反应的抑制机理，以确定催化剂在SCR脱硝协同CVOCs氧化反应的构效关系和决定反应的关键因素，并用于指导催化剂配方优化，在开拓新型低温双功能催化体系和开发高效协同控制多污染物技术方面取得创新性成果。