Abstract: The coupling reaction of ethane dehydrogenation with reversed water-gas shift reaction over Cr/SiO2 catalysts was studied. The Cr/SiO2 catalyst promoted by Mn oxide has already been found to be active and selective in the reaction at around 740 ℃, with the selectivity to ethylene of about 99.7% at 47.7% ethane conversion. XPS results showed that Cr6+, Cr3+ and Mn4+ occupied on the surface of the catalysts. The addition of Mn benefited the redox cycle between reactants and catalyst and enhanced reaction activity.

Key words: ethane dehydrogenation, ethylene, reversed water-gas shift, Cr-Mn/SiO2 catalysts

摘要： 分别制备了以Mn、Ce、Cu、Zn、K等为助剂的Cr/SiO2催化剂，考察了助剂在逆水煤气变换耦合乙烷脱氢制乙烯反应中对Cr/SiO2催化剂反应性能的影响。结果表明，高温下Mn的加入有利于催化活性的提高，Cr-Mn/SiO2催化剂显示了较好的催化活性。在740 ℃、n(CO2)/n(C2H6)＝7的条件下，乙烷转化率为47%，乙烯选择性为99%。XRD、XPS、UV-DRS和TPR技术的表征表明催化剂表面存在Cr3+、Cr6+、Mn4+物种，Mn的加入使得催化剂还原性能增强，有助于反应过程中氧化还原循环的进行，提高了反应活性。

关键词: 乙烷脱氢, 乙烯, 逆水煤气变换, Cr-Mn/SiO2催化剂