Different influences of V2O5/Al2O3 introduction on initial conversion of n-heptane over fresh and equilibrium ZSM-5 catalyst

摘要

Previous studies showed that the introduction of V2O5/Al2O3 could improve catalytic performances of ZSM-5 catalyst for n-heptane cracking. In order to clarify influences of V2O5/Al2O3 introduction on the initial reaction of n-heptane, performances of n-heptane cracking over fresh and equilibrium ZSM-5 catalyst without and with V2O5/Al2O3 introduction were comparatively studied in this paper. The results showed that the introduction of V2O5/Al2O3 brought significant influences to initial reactions of n-heptane over the equilibrium ZSM-5 catalyst. The initial reaction rate was significantly improved, and the product selectivity was greatly changed by V2O5/Al2O3 introduction. But no such effect was observed for the fresh ZSM-5 catalyst. It was supposed that the presence of V2O5/Al2O3 offered another pathway for initial conversion of n-heptane, and this reaction path played a more important role in the reaction over the mixed V2O5/Al2O3 and equilibrium ZSM-5 catalyst. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.