Zhang Yu-cai, Bo Long-li, Wang Xiao-hui, Liu Hai-nan, Zhang Hao
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Huan Jing Ke Xue. 2012 Aug;33(8):2759-65.
The performance in catalytic oxidation of benzene was investigated in two different heating modes, microwave heating and conventional electric furnace heating. The effects of copper (Cu)-manganese (Mn) mass ratio, doping dose of cerium (Ce) and calcination temperature on the catalytic activity of Cu-Mn-Ce/molecular sieve catalyst were also checked in catalytic oxidation of benzene with microwave heating, and the catalysts were subsequently characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that the catalyst had better catalytic activity for the oxidation of benzene under microwave heating than electric furnace heating, and high oxidation efficiency for benzene was reached due to the "local hot spots" and dipole polarization effect of microwave and stable bed reaction temperature. Under the conditions of Cu, Mn and Ce mass ratio 1:1:0.33 and calcination temperature 500 degrees C, the catalyst had the optimal catalytic activity for benzene oxidation, and its light-off temperature and complete combustion temperature were 165 degrees C and 230 degrees C, respectively. It was indicated by characteristics of XRD and SEM that the presence of copper and manganese oxides and Cu1.5Mn1.5O4 with spinel crystal improved the catalytic activity of the catalyst, and the doping of Ce promoted the dispersion and regularization of active components. High calcination temperature led to the sintering of the catalyst surface and agglomeration of active components, which decreased the catalytic activity of the catalyst in the catalytic oxidation
在微波加热和传统电炉加热两种不同加热模式下研究了苯的催化氧化性能。在微波加热苯的催化氧化过程中，还考察了铜（Cu）-锰（Mn）质量比、铈（Ce）掺杂量和煅烧温度对Cu-Mn-Ce/分子筛催化剂催化活性的影响，随后用扫描电子显微镜（SEM）和X射线衍射（XRD）对催化剂进行了表征。结果表明，与电炉加热相比，该催化剂在微波加热下对苯的氧化具有更好的催化活性，由于微波的“局部热点”和偶极极化效应以及稳定的床层反应温度，实现了对苯的高氧化效率。在Cu、Mn和Ce质量比为1:1:0.33且煅烧温度为500℃的条件下，该催化剂对苯氧化具有最佳催化活性，其起燃温度和完全燃烧温度分别为165℃和230℃。XRD和SEM表征结果表明，铜锰氧化物以及具有尖晶石晶体结构的Cu1.5Mn1.5O4的存在提高了催化剂的催化活性，Ce的掺杂促进了活性组分的分散和规整化。较高的煅烧温度导致催化剂表面烧结和活性组分团聚，从而降低了催化剂在催化氧化中的催化活性。
