Catalytic performance of the exchanged Y faujasites by Ce3+, La3+, UO22+, Co2+, Sr2+, Pb2+, Tl+ and NH4+ cations in the disproportionation reaction of toluene

The catalytic performance of exchanged Y faujasites by Ce3+, La3+, UO22+, Co2+, Sr2+, Pb2+, Tl+ and NH4+ ions were studied in a disproportionation reaction in the gaseous phase. It was shown that total acidity generated by exchanged ions is responsible of the catalytic activity. Rare earths (cerium, lanthanum and uranium) catalysts have appreciable performance and allowed one to obtain an important xylenes proportion at 400 to 450 C. The decrease of xylenes and trimethyl-benzenes proportion in studied catalysts shows the implication of xylenes in toluene disproportionation reaction. (authors)