Catalysis Letters, Vol.147, No.7, 1704-1713, 2017
Influence of Zirconium Modified USY on Coupled Hydrogenation and Ring Opening of Tetralin Over NiW/USY + Al2O3
There is increasing interest in modification USY in hydrotreating catalysts to attain high activity and targeted product selectivity. Zirconium modification on USY (Zr-USY) was designed in this study. Zirconium highly dispersed, and greatly enriched on the surface of USY zeolites. Zirconium modification slightly induced framework dealumination. Introduction of zirconium increased total acid sites of USY zeolites, probably ascribed to Zr4+ polarizing H2O. The corresponding catalysts NiW/Al2O3 + Zr-USY-1 (40.6 wt%) and NiW/Al2O3 + Zr-USY-2 (41.4 wt%) showed higher selective ring opening products yield compared to NiW/Al2O3 + USY (31.7 wt%). The enhanced ring opening products yield may be due to sufficient cooperation between WS2 and acidity. The results provide further insight into USY modification and its role on hydrotreating catalysts.
Keywords:Zr-USY;Acid sites;WS2;NiW-based catalyst;Hydrogenation and selective ring opening catalysts