Cotransformations of n-Hexadecane, Hexene-1, and Cyclohexane over Dual-Zeolite Cracking Catalysts

Abstract

Characteristic features of the conversion of n-hexadecane, hexene-1, cyclohexane, and their mixtures over dual-zeolite catalysts for co-cracking of light and heavy fractions are considered. The maximum yield of olefins (the yield of C₂–C₄ olefins reaches 66.8 wt %) is achieved in the case of the use of hexene-1 possessing maximum reactivity under cracking conditions as a feedstock. Cotransformation of n-hexadecane and hexene-1 do not indicate the presence of any significant interaction between the components. The presence of cyclohexane in the feedstock has substantial influence on the transformation of n-hexadecane, which is due to the high hydrogen donor ability of naphthenes. It is found that the ratio of HREEY and P/HZSM-5 zeolites in the composition of the catalyst has substantial influence on the value of the interaction between the components of the feedstock. The use of hydrocarbons containing “labeled” hydrogen atoms (deuterium) makes it possible to estimate the distribution of the naphthene hydrogen between the main gaseous products.