The influence of HZSM-5 zeolite on the product composition after cracking of high boiling hydrocarbon fractions

Abstract Cracking of hydrogenated vacuum distillate was investigated on a Y-type zeolite containing catalyst, on a HZSM-5 zeolite (silicon-to-aluminium ratio=35) and on a 1:1 mixture of both. In presence of HZSM-5 the yield of gas increases at the expense of the gasoline yield. In the gasoline fraction a significant enrichment of aromatics takes place, both by cracking of olefinic and paraffinic compounds in this boiling range and by formation of aromatics from gaseous olefins.