【摘要】 采用回流法合成了OMS-2,同时以OMS-2为载体,采用浸渍法负载CeO₂制备了Ce/OMS-2催化剂,运用X射线衍射、拉曼光谱、BET、H₂-TPR和NH₃-TPD等方法对催化剂进行表征,并考察CeO₂/OMS-2催化剂催化氧化二氯甲烷和乙酸乙酯的性能。结果表明,CeO₂的加入并未改变OMS-2较好的八面体分子筛结构,CeO₂的晶粒很小且以高分散的形式存在;负载CeO₂的OMS-2催化剂比表面积都有增大趋势;随着CeO₂负载量的增加,低温和高温的还原峰都先向低温方向偏移再向高温方向偏移;随着CeO₂负载量的增加,高温处强酸性峰先向低温方向偏移再向高温方向偏移。反应活性结果表明,CeO₂/OMS-2催化剂活性比载体OMS-2的活性好,随着铈负载量的增加,催化活性先升高再降低,其中,CeO₂负载质量分数为1.0%（1.0Ce/OMS-2）时催化剂效果最好,这可能是由于铈的加入活化了OMS-2中的氧,影响了整体催化剂的酸性,进而影响反应性能。更多还原

【Abstract】 OMS-2 was synthesized using a reflux method,and CeO₂/OMS-2 catalysts were prepared by the impregnation method. The as-prepared catalysts were characterized by XRD, Raman, BET, H₂-TPR and NH₃-TPD techniques. The performance of CeO₂/OMS-2 catalysts for catalytic oxidation of dichlo-romethane and ethyl acetate were investigated. XRD results indicated that the octahedral molecular sieve structure of OMS-2 was not changed with the addition of CeO₂ and CeO₂ particles were highly dispersed on the surface of OMS-2. BET results showed that the surface area of the catalyst increased with the addition of CeO₂. H₂-TPR results indicated that with the increase of CeO₂ loadings,low temperature and high temperature reduction peaks first shifted to low temperature and then to high temperature. NH₃-TPD results indicated that with the increase of CeO₂ loadings, high temperature desorption peak assigned to strong acid first shifted to low temperature and then to high temperature. The results of reaction activity showed that the activity of Ce/OMS-2 catalysts were better than that of OMS-2 support. The highest reac- tivity was obtained over 1. 0Ce/OMS-2 catalyst （CeO₂ loading mass fraction 1.0% ） , probably due to the enhanced oxygen mobility and the weakened acidity of the catalyst by the addition of CeO₂.更多还原