摘要
研究CeO2改性得到的CuO/CeO2/沸石催化剂,进行催化氧化(燃烧)销毁乙醇、丙酮、甲苯和苯的实验,并用TPR和XPS对所制备的催化剂进行表征。研究结果表明:使用CuO/CeO2/沸石作为催化剂时,四种VOCs(挥发性有机物)催化燃烧的起燃和完全燃烧温度都明显低于当使用CuO/沸石作为催化剂时四种VOCs催化燃烧的起燃和完全燃烧温度,这表明CuO/CeO2/沸石催化剂的活性明显高于CuO/沸石催化剂的活性。TPR分析表明CeO2的添加有助于增强催化剂中Cu的还原性;XPS表征分析显示,CeO2的添加增加了铜在表面的分布,并且引起Cu2p3/2的结合能由933.8eV变到932.8eV和933.4eV,在催化剂表面呈现出Cu2+和Cu+的形式。此外,在VOCs催化燃烧过程中,稀土Ce存在有部分还原变价过程(Ce4+→Ce3+),也使催化剂的活性得到提高。
CuO/CeO2/zeolite catalysts were prepared by doping CeO2 on CuO/zeolite. Experiments of the catalytic oxidation/combustion of some volatile organic compounds （VOCs）, ethanol, acetone, toluene and benzene, were carried out over the catalysts. The ceria doped catalysts were characterized respectively by temperature-programmed reduction with H2 （H2-TPR） and X-ray photoelectron spectroscopy （XPS）. Results show that the light-off temperature and total conversion temperature of catalytic oxidation reaction of the VOCs on CuO/CeO2/zeolite are much lower than those on CuO/zeolite and the activity of CuO/CeO2/zeolite is much higher than that of CuO/zeolite. The TPR results show that the addition of CeO2 increases the reducibility of Cu. The XPS results indicate that CeO2 doping greatly promotes the surface copper distribution and makes the binding energy of the Cu 2p3/2 level decreases from 933.8 eV to 932.8 eV and 933.4 eV, which indicates that Cu existes on the catalyst surface in the form ofCu^2＋ and Cu^＋, and the XPS also discloses that the reduction ofCe^4＋ to Ce^3＋ during the catalytic combustion is beneficial to catalytic activity.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2005年第6期776-780,共5页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金资助项目(20336020)
教育部博士点基金(20020561010).
