The function of Cu(II) ions in the Mo/CuH-ZSM-5 catalyst for methane conversion under non-oxidative condition

Non-oxidative aromatization of methane was carried out over Mo/CuH-ZSM-5 an d compared with that over Mo/H-ZSM-5. Cu(II) ions act as promoter in this r eaction and improve the activity of the Mo/H-ZSM-5 catalyst notably. The ef fect of Cu species on the chemical state of Mo species and the changes of C u species itself after reaction were studied by ESR and XPS methods. The in troduction of Cu ions by ion-exchange method altered the reduction of Mo sp ecies, suppressed the dealumination of ZSM-5 framework and decreased coke f ormation over the catalyst. The results showed improved catalytic performan ce of Mo/H-ZSM-5 catalyst. The amount and nature of the coke which were inf luenced by the introduction of Cu ions were also investigated. (C) 1999 Els evier Science B.V. All rights reserved.