Influence of Ga content on the acidic characteristics and methanol to aromatics performance of Ga-ZSM-5 zeolites

Ga-ZSM-5 zeolite has excellent performance for methanol to aromatics (MTA) reactions, but introducing Ga metal into ZSM-5 zeolite leads to a complex acid species. The present study investigated the effect of Ga metal content on the acid amount and MTA reaction products in the hydrothermal synthesis of Ga-ZSM-5 zeolite. Lewis acid mainly formed at a Ga/Al ratio below 2.0, and at a Ga/Al ratio higher than 2.0, framework Ga species formed, increasing Brønsted acid content. Ga 2.0 -ZSM-5 zeolite exhibited the lowest B/L acid ratio (0.48), excellent BTX selectivity (40.26%), and the highest H 2 selectivity (8.93%). This finding indicates the most pronounced synergistic hydrogenation of Brønsted and Lewis acids. Ga 3.0 -ZSM-5 produced more xylene with more Brønsted acid compared to Ga 1.0 -ZSM-5, although they both had the same B/L acid ratio. The alterations in acidic species at different content of Ga metal appear to be conducive to the regulation of acidity in Ga-ZSM-5 zeolites.