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采用溶胶-凝胶法和浸渍法制备选择性催化还原(SCR)脱硝反应复合纳米催化剂Ce-V/TiO2,在不同的实验条件下制备出一系列的TiO2凝胶用作催化剂载体。然后通过浸渍法依次负载CeO2和V2O5于多孔TiO2载体。用氨气作为还原性气体,对选择性催化还原NOx进行实验研究。在不同的TiO2载体煅烧温度、CeO2和V2O5负载量以及催化还原反应温度等条件下,对催化剂的表面结构和催化性能采用BET、XRD、SEM等手段进行表征分析。结果表明,纳米Ce-V/TiO2固溶体复合催化剂以及对其制备工艺技术参数的优化可增大催化剂的比表面积和微孔体积,使催化剂的催化活性有很大的提高。此外,相当数量的多孔纳米TiO2大大增加了光催化活性的有效面积,有利于增大与反应物的接触面积和提高光催化活性。当载体TiO2的煅烧温度和催化还原反应温度为500℃时,5%Ce-10%V/TiO2催化剂反应的NOx转化率可达96.2%。
Selective catalytic reduction (SCR) denitration reaction of composite nano-catalyst Ce-V / TiO2 was prepared by sol-gel method and impregnation method. A series of TiO2 gels were prepared under different experimental conditions for use as catalyst carriers. Then by impregnation followed by loading of CeO2 and V2O5 porous TiO2 carrier. Ammonia was used as reductive gas to study the selective catalytic reduction of NOx. The surface structure and catalytic properties of the catalyst were characterized by BET, XRD and SEM under different conditions of calcination temperature of TiO2 carrier, CeO2 and V2O5 loading and catalytic reduction temperature. The results show that the nano-Ce-V / TiO2 solid solution composite catalyst and the optimization of its technical parameters can increase the specific surface area and the micropore volume of the catalyst, greatly improving the catalytic activity of the catalyst. In addition, a considerable amount of porous nano-TiO2 greatly increases the effective area of the photocatalytic activity, which increases the contact area with the reactants and improves the photocatalytic activity. When the calcination temperature and catalytic reduction temperature were 500 ℃, the conversion of 5% Ce-10% V / TiO2 catalyst reached 96.2%.