正己烷在铂铬重整催化剂上的反应

The Conversion of n Hexane over Pt Cr Catalyst

考察了在连续流动条件下，正己烷在铂铬重整催化剂上的反应行为。结合ＴＰＲ、环己烷脱氢及异丙苯裂解等手段，研究铬的还原特性及其对催化剂双功能的调变。结果表明，低铬质量分数的催化剂（当ｗ（铬）＝３．００％时），不仅能提高铂催化剂的芳构化产率，抑制氢解，且能保持铂催化剂的初活性和稳定性。但催化剂中铬的质量分数较高时，铬破坏了催化剂原有的双功能匹配，使高铬质量分数催化剂性能呈现劣势。铬的这种作用与它本身的可还原程度及其对催化剂的调变功能密切相关。铬的引入使铂催化剂的金属功能略有下降，更主要的是调变了催化剂的酸功能。当双功能相互匹配时，铂铬催化剂才体现较好的催化剂的反应性质。

The performance of Pt Cr/Al 2O 3 in the conversion of n hexane in the presence of H 2 has been investigated in a continuous flow microreactor.TPR,cyclohexane dehydrogenation and cumene cracking are used to characterize the reduction reaction and the effect of Cr on bifunctionality.The results indicated that the catalytic performance of Pt Cr catalyst is dependent on the Cr content.Low loadings(with 3 00 % Cr content)lead to an increase in aromatic yield and to suppression of hydrogenolysis.Furthermore,the additives hardly change the initial activity and stability.However,these are reduced at high loadings due to the effect of Cr on the bifunctionality.These characteristics are related with the reduction and the effect of Cr on the bifunctionality.Cr slightly reduces the metallic function and significantly varies the acidic function.Catalytic performance of Pt Cr catalyst is promoted when the bifunctionality of the catalysts matches with each other.