Mn and Zn doped ZSM-5 zeolite catalysts

Manganese was incorporated into a ZSM-5 zeolite by a special impregnation method which practically prevented the deposition of the metal ions on the internal surface of the zeolite pores. As a result, the production of light olefins increased sharply while that of aromatics did not significantly change. The double incorporation of Zn (by ion-exchange) and of Mn (by this impregnation technique) led to catalysts which could produce more aromatics and more light olefins (mainly ethylene and propylene) than the parent ZSM-5 zeolite.