Propane Aromatization Tuned by Tailoring Cr Modified Ga/ZSM-5 Catalysts

Graphical Catalytic propane aromatization : Post-introducing Cr species to Ga/Z5 catalyst had the maximum dehydrogenated active Cr 3+ species. Propane was effectively converted, and more light alkenes from propane dehydrogenation were converted into BTX on 2Cr/GaZ5 catalyst. Active Cr 3+ species and strong interaction between Ga species and ZSM-5 zeolite on 2Cr/GaZ5 catalyst accelerated the dehydrogenation step in propane aromatization. Accelerating propane dehydrogenation in propane aromatization is vital because it is the first and rate control step. In this study, we introduced Cr to Ga/ZSM-5 by tuning its impregnation sequence and amount, which was expected to accelerate the dehydrogenation step and improve aromatization performance. The impregnation sequence of Cr on catalyst not only affected the interaction between Ga and ZSM-5, but also tuned the amount of dehydrogenation active species Cr 3+ . Due to the plenty of Cr 3+ species and strong interaction between Ga species and ZSM-5, 2Cr/GaZ5 catalyst accelerated the dehydrogenation step and improved the aromatization process. More light hydrocarbons were preferred to be produced and were further converted into BTX on 2Cr/GaZ5 catalyst. Excessive Cr on catalyst caused the formation of Cr 2 O 3 particles with worse dispersion. The aggregated Cr 2 O 3 decreased the strong acidity of catalyst, which could not further promote propane conversion and decreased the aromatization ability of catalyst.