苯甲酸还原制苯甲醛CeO_2催化剂性能研究

Performance of CeO_2 catalyst for hydrogenation benzoic acid to benzaldehyde

制备并表征了Cat600和Cat800两种CeO2催化剂,考察它们对苯甲酸加氢还原制备苯甲醛的催化性能和寿命.发现两种催化剂的性能皆随反应时间延长而下降,Cat600的性能和稳定性较好.元素分析(EA)证实催化剂表面积炭是导致失活的主要原因.热重/差热分析(TG/DTA)结果表明存在两种类型的积炭.X射线衍射(XRD)结果分析得出晶胞增大和部分CeO2晶相发生破坏也会使活性下降.分别对两催化剂进行了10次性能考评和9次再生,结果表明,失活催化剂在450℃下清除积炭,可使活性很好地得到恢复,Cat600具有更好的可再生性能.

Two kinds of CeO2 catalysts, Cat600 and Cat800, were prepared and investigated for hydrogenation of benzoic acid to benzaldehycle. Both of the two catalysts deactivate with the time on stream, and Cat600 shows better performance and stability. Element analysis （EA） confirms that coke formation on catalyst surface is mainly responsible for catalyst deactivation. Thermogravimetry/differential thermal analysis （TG/DTA） results reveal that two kinds of coke exist. X-ray diffraction （XRD） results indicate that increasing of crystalline size and crystalline disaggregation can also result in catalyst deactivation. According to investigations of catalytic and regeneration performances for 10 and 9 times respectively, the catalytic performance of deactivated catalysts can mainly be regenerated by eliminating the coke at 450 ℃ by air, and Cat600 shows better regeneration performance.