Study on alkylation reaction of thiophenic compounds for desulfurization of fcc gasoline on zeolite catalysts

摘要

Zeolite catalysts HY,Hbeta,HZSM-5,and SAPO-llwere investigated in the alkylation reaction of thiophenic compounds.As a result,HZSM-5,which has large contents of both strong acid sites and BrOnsted acid sites,had the highest alkylation activity and selectivity.Certain sulfur-containing impurities could be converted to higher molecular weight products with the boiling point in the range of that of diesel fraction.Sulfur compounds' cracking in this research is simultaneously not an undesirable reaction.ZSM-5 type zeolite has its unique tunnel structure,and therefore there was no resinification of thiophenic compounds.At the same time,olefins extensive oligomerization was not been found and coke yield was very low,which would lead high yield of gasoline products.Based on quantum mechanics,kinetic minimum cross-sectional diameter and diffusion energy of some sulfur compounds were given by molecular simulation techniques.The mechanism of alkylation of thiophenic compounds with olefins was proposed.