铜锰铈三元催化剂的制备及其催化燃烧甲苯性能的研究

发布时间：2018-03-04 20:01

  本文选题：铜锰铈　切入点：负载量　出处：《浙江工业大学》2016年硕士论文　论文类型：学位论文

【摘要】：鉴于贵金属过高的成本,铜锰氧化物作为常见的过渡金属氧化物常被用于催化氧化有机挥发性污染物(VOCs)。CeO_2具有较好的储氧功能,常与铜锰氧化物形成二元或三元催化剂来提高催化剂的催化性能。本论文中,采用浸渍法制备了以TiO_2为载体的铜锰二元复合氧化物催化剂和铜锰铈三元复合氧化物催化剂。通过XRD、BET和H2-TPR表征技术考察了Cu/Mn摩尔比及负载量、Cu/Mn/Ce摩尔比及负载量对催化剂晶相结构和氧流动性的影响。然后,采用溶胶凝胶法制备了铜锰铈三元复合氧化物催化剂,通过XRD、BET和H2-TPR表征技术考察了焙烧温度对催化剂晶相结构和氧流动性的影响。并采用常压气-固反应装置以甲苯作为探针反应,评价催化剂催化燃烧甲苯的性能和稳定性。得到的结果如下所示:1.采用浸渍法制备的Cu-Mn/TiO_2催化剂在焙烧温度为500℃时通过固相反应生成了复合氧化物Cu1.4Mn1.6O4。在复合氧化物Cu1.4Mn1.6O4中,铜锰之间的协同作用提高了催化剂的催化氧化性能。当Cu/Mn摩尔比为1:1、负载量为30%时,铜锰二元氧化物催化剂的催化性能最佳,其T95为277.5℃。2.采用浸渍法制备Cu/Mn/Ce摩尔比为1:1:4、负载量为30%的铜锰铈三元氧化物催化剂催化性能最佳,其T95为274.7℃。CeO_2的加入可以提高Cu1.4Mn1.6O4的分散度,提高了氧的流动性,从而降低了催化剂的H2-TPR还原峰温。进而提高了催化剂的催化氧化性能。且催化剂有很好的稳定性,在275℃下反应30天,转化率和选择性不变。3.与浸渍法制备的负载型铜锰铈氧化物催化剂(负载量为30%、摩尔比为1:1:4)相比,溶胶凝胶法制备的铜锰铈三元复合氧化物催化剂(摩尔比为1:1:4、焙烧温度为500℃)催化性能更佳,其T95为236.2℃。主要由于溶胶凝胶法制备的不加载体的催化剂活性组分具有更大的比表面积,活性中心(CuO,Cu1.4Mn1.6O4等)分散度更高,形成的活性位点更多,从而提高了催化剂催化氧化甲苯的性能。此外,催化剂有很好的稳定性,在236℃下反应30天,转化率和选择性基本不变。
[Abstract]:In view of the high cost of precious metals, Cu-Mn oxides, as common transition metal oxides, are often used to catalyze the oxidation of volatile organic pollutants (VOCsN). CeOSP _ 2 has a better oxygen storage function. Binary or ternary catalysts are often formed with Cu-Mn oxides to improve the catalytic performance of the catalysts. The copper-manganese binary oxide catalysts and copper-manganese cerium ternary oxide catalysts supported on TiO_2 were prepared by impregnation method. The molar ratio of Cu/Mn and the amount of supported Cu / mn / ce were investigated by XRDX BET and H2-TPR characterization techniques. Effect of catalyst phase structure and oxygen fluidity. Then, The copper-manganese and cerium ternary oxide catalysts were prepared by sol-gel method. The effects of calcination temperature on the crystal structure and oxygen fluidity of the catalyst were investigated by means of XRDX BET and H2-TPR characterization techniques, and toluene was used as a probe in the atmospheric pressure gas-solid reactor. The performance and stability of catalyst for toluene combustion were evaluated. The results are as follows: 1. The Cu-Mn/TiO_2 catalyst prepared by impregnation method has been prepared by solid state reaction at 500 鈩，

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