Cracking of long chain n-paraffins on silica—alumina and rare earth exchanged Y zeolite

Abstract

Abstract The present work reports for the first time a study of cracking of model paraffinic compounds in the boiling range of vacuum gas oil. The cracking reactions are investigated on commercial silica—alumina catalysts and rare earth exchanged Y zeolite (RE-Y) using the ASTM procedure for microactivity test. Effect of alumina content, temperature and hydrothermal treatment on activity and product selectivity is studied. Increase in alumina content results in higher activity without significant difference in product selectivity. Hydrothermal treatment results in decrease in the quantity of C 1 -C 4 products. RE-Y exhibited higher activity as compared to silica—alumina. The yield of gasoline and middle distillate range products was found to be higher on RE-Y. The product patterns are analysed on the basis of a detailed mechanism in the following paper.