【作者】 李贤均； 黄益平； 谢蕙； 杜宗英；

【Author】 Li Xianjun,Huang Yiping,Xie Hui and Du Zhongying (Department of Chemistry,Sichuan University)

【机构】 四川大学化学系； 西南化工研究院； 四川大学分析测试中心；

【摘要】 <正>表面氢溢流是负载型金属催化剂上较普遍的现象,它不仅与金属性质有关,也与载体性质和引入的其它元素有关,而且和金属催化剂的加氢活性有密切联系。用红外光谱法研究催化剂表面上氢-氘同位素交换反应,对了解铂原子簇衍生出的催化制和传统铂催化剂上氢溢流的差别,认识氢在催化剂表面上的活化和迁移过程机理很有帮助。更多还原

【Abstract】 H-D exchange,which occurred in OH groups on the surface of the catalysts derived from Pt3（CO）₃（PPh₃）₄/γ-Al₂O₃（I）,Pt₄（CO）₅（PPh₃）₄/γ-Al₂O₃(ID,and H₂PtCl₆/ Y-Al₂O₃（IE）,was studied by IR.The exchange processes were in situ measured under evacuated condition in an IR cell. The results showed that the rates of H-D exchange on the catalysts I and II were about twice as fast as that on theⅢ,but the rate of H-D exchange onγ-Al₂O₃ was very slow.The fast exchange rates on the catalyst I and II were related to the high dispersions of platinum and were in agreement with the high activities in benzenehydrogenation.Phosphorus contained in the catalystⅠand II was favourable for platinum dispersion and hydrogen activation.A mechanism of hydrogen activition and spillover on the catalyst surface was suggested.According to the mechanism the migration of the active hydrogen atom on the surface was the rate-determining step in hydrogen spi1lover.更多还原