Direct evidence for the incorporation of univalent indium into high-silica zeolite, H-ZSM-5, by thermal auto-reductive solid-state ion exchange.

In mechanical mixtures of H-ZSM-5 and In2O3 thermal auto-reductive solid-state ion exchange (AR-SSIE) was found to proceed upon treatment in high vacuum at 840 K resulting in the incorporation of In+ ions into, and in an increase of the thermal stability of, the zeolitic component.