稀土金属氧化物负载氧化铜纳米催化材料对VOC燃烧的催化作用研究

【作者】 杨东；

【导师】 陈霭璠；

【作者基本信息】 北京化工大学 ， 工业催化， 2004， 硕士

【摘要】 VOC是工业生产中大量排放的废气，通过催化燃烧将有机废气转化为无害的CO2和H2O是处理有机废气（VOC）的有效方法，不仅可以消除它对大气的污染，而且还可还可以回收利用燃烧释放的热量。与普通燃烧方式相比，催化燃烧是无焰燃烧，VOC与空气进行预混合后，均匀通过催化剂床层，在活性粒子的催化作用下实现燃烧，具有很高的燃烧效率，而且催化燃烧能显著降低燃烧温度，避免了其燃烧时将空气中氮气同时氧化，形成氮氧化物，从而避免了酸雨的产生。VOC催化燃烧所用的催化剂很多，基本可分为有贵金属催化剂和过渡金属催化剂两大类。CuO被认为活性最高的过渡金属氧化物活性组分之一，被广泛用于催化氧化－还原反应中。负载CuO催化剂被认为是贵金属催化剂的潜在替代品，因而于近年得到广泛的关注。本论文尝试以CuO为活性组分，CeO2 为载体，制备成CuO/CeO2和CuXCeOδ催化材料，以甲烷燃烧为模型反应对其催化活性进行了评价，并对其进行了表征。在此基础上，用ZrO2对其进行了掺杂，制备成Cu0.08ZrXCe!-X(X=0.2,0.4,0.6,0.8)三元催化材料，同样对其对甲烷燃烧的催化活性进行了评价，并对其进行了表征。本论文的成果如下：1, 用浸渍法，共沉淀法，溶胶－凝胶法和柠檬酸络合法制备了CuO/CeO2和CuXCeOδ（X＝0.01,0.04,0.08,0.12,0.15）二元催化材料，分别评价了对甲烷燃烧的催化活性进行，得到了不同方法制备的催化材料达到最佳催化活性时的CuO含量，并考察了不同焙烧温度对催化材料活性的影响。2, 柠檬酸络合法制备了Cu0.08ZrXCe!-X(X=0.2,0.4,0.6,0.8)三元催化材料，评价了对甲烷燃烧的催化活性，。得到了不同方法制备的催化材料达到最佳催化活性时的锆铈比。并考察了不同焙烧温度对催化材料活性的影响。 <WP=4>3,用XRD，BET，TEM, TG-DTA，激光粒度分析仪等手段对各种催化材料的性能进行了表征，考察了各种催化材料的形貌。4,初步探讨了该系列催化材料对甲烷燃烧的催化作用机理。更多还原

【Abstract】 Volatile Organic compound(VOC) comes massively from industrial production ,as main air pollutant. Catalytic combustion is an exclusively effective method for the removal of VOC, in which toxic VOC is totally decomposed ino H2O and CO2. Moreover, heat coming from the catalytic combustion may be re-used. Compared with conventional combustion, catalytic combustion is fameless, in which VOC is pre-mixed with air, then passes homogenously catalyst bed and burned efficiently. More significantly，because catalytic combustion may be performed under lower temperature, N2 in air is free of being oxidized into NOX, which is responsible for the formation of acidic rain ,at the same time when catalytic combustion happens.There are many kinds of catalysts used in catalytic combustion, generally including noble metal catalysts and transition metal oxide catalysts. Regarded as one of the most active component , CuO is used widely in catalysts for redox reactions. The catalysts , CuO loaded on carriers , are thought of the potential substitutes of noble metal catalysts, which have excellent low-temperature activities, and are paid more attention in recent years.In this paper, CuO/CeO2和CuXCeOδ catalytic materials were prepared, in which CuO was active component, CeO2 was carrier. Employing CH4 combustion as the probe reaction, the activities of these catalytic materials were measured. Their properties were characterized. Then, doped with ZrO2, Cu0.08ZrXCeOδcatalytic materials were prepared. As the same as the above, their activities were measured and their properties were characterized.The works we have done in this paper are below:1,Two-component catalytic materials,CuO/CeO2 and CuXCeOδ(X＝0.01,0.04,0.08,0.12,0.15),were prepare by impregnation method ,co-precipitation method and citric method. Their activities were measured in methane combustion. <WP=5>The optimal CuO content and the influence of calcination temperature on activities were detected.2,Three- component catalytic materials, Cu0.08ZrXCe!-X(X=0.2,0.4,0.6,0.8), were prepared by citric method. Their activities were measured in methane combustion. The optimal ratio of Ce/Zr and the influence of calcination temperature on activities were detected.3, The properties and appearances of catalytic materials were characterized with XRD，BET，TEM, TG-DTA and laser diameter analyst.4, Catalytic mechanism of the prepared catalytic materials were discussed simplely.更多还原