Electrochemical promotion of catalysis for pollution control

涉及氮氧化物(NOx)、碳氢化合物、挥发性有机化合物和一氧化碳的催化转化的反应对于消除固定来源和汽车来源的有毒排放具有重要的环境意义。利用多相催化，有毒化合物可以转化为无害的非污染物。在氧气过剩的情况下，通过轻烃还原氮氧化物，这是稀燃和柴油发动机排气的典型特征，这是一个巨大的技术挑战。传统催化剂存在成本高、寿命短、在催化过程中不能控制其活性等缺点。最近发现的电化学促进催化(EPOC)与经典的多相催化相结合的现象可以用来克服上述一些问题。固体电解液支撑的金属或金属氧化物薄膜的催化剂-电极电位的可控变化导致了催化活性和选择性的显著变化。已经证明，电化学促进不限于任何特定的电解液、导电催化剂或反应类型。EPOC商业化的主要障碍是缺乏有效的催化剂和反应器设计。拟议研究计划的目标是开发有效的系统设备来去除有毒污染物(NOx、碳氢化合物、一氧化碳等)。利用电化学法促进柴油和稀燃汽车尾气的排放。短期和中期的总体目标是设计具有特定尺寸和结构的纳米结构催化剂，并将其应用于NOx还原。长期目标是建立对纳米结构催化剂的电化学促进作用的全面理解。这一跨学科研究的重大成果将回答多相催化中的许多基本问题，并导致纳米催化系统用于空气污染防治的新阶段。

Reactions involving the catalytic conversion of nitrogen oxide (NOx), hydrocarbons, volatile organic compounds and carbon monoxide are of major environmental importance for the removal of toxic emissions from both stationary and automotive sources. Toxic compounds can be converted to harmless non-pollutants using heterogeneous catalysis. The reduction of nitrogen oxides by light hydrocarbons in the presence of excess of oxygen, typical of the exhaust of lean-burn and Diesel engines, presents a great technological challenge. Conventional catalysts show several disadvantages, such as high cost, short life time, and fail to control their activity during the catalytic process. The recently discovered phenomenon of Electrochemical Promotion of Catalysis (EPOC) combined with classical heterogeneous catalysis could be applied in order to overcome some of the above mentioned problems. The controlled variation in the catalyst-electrode potential of metal or metal oxide films supported on solid electrolytes is responsible for considerable changes in catalytic activity and selectivity. It has been demonstrated that electrochemical promotion is not limited to any particular electrolyte, conductive catalyst, or type of reaction. The major obstacles towards commercialization of EPOC are the lack of efficient catalysts and reactor design. The objective of the proposed research program is to develop efficient system devices for the removal of the toxic pollutants (NOx, hydrocarbon, carbon monoxide, etc.) from Diesel and lean-burn automobile exhausts using electrochemical promotion. The overall goal in the short to medium term is to design nano-structured catalysts of defined size and structure, and their application to NOx reduction. The long term objective is to establish a comprehensive understanding of the electrochemical promotion with nano-structured catalysts. The significant output of this interdisciplinary research will answer many fundamental questions in heterogeneous catalysis and lead to a new stage of nano-sized catalytic systems for air pollution prevention.