Isomerization of heptane on molybdenum oxide catalysts with a small amount of nickel

Abstract

The catalytic performances of molybdenum oxides for the isomerization of heptane have been investigated at 623 K under atmospheric pressure. After a long induction period, MoO₃ became an active and selective catalyst for this reaction. The catalytic activity, however, declined gradually with time on stream. Loading small amounts of Ni onto MoO₃ was effective in stabilizing the isomerization activity without a change in isomerization selectivity. The isomerization activity became stable against deactivation when Ni/SiO₂ was mixed with MoO₃. We conclude from these results that Ni acted as a port of spilled-over hydrogen, which stabilized the isomerization activity of MoO₃.