Isoamylene Dimerization\nover Mesoporous Y Zeolites

Oligomerization of alkenes is a promising\nway for production\nof\nhigh-quality and eco-friendly liquid fuels, where zeolite catalysts\nare critical. In the zeolite catalysts, mass transfer and accessibility\nin the reaction are normally influenced by intrinsic micropores of\nzeolites, in particular, bulky or branched molecules are employed.\nHere, we report isoamylene (2-methyl-2-butene) dimerization over mesoporous\nHY zeolites obtained by facile NaOH treatments. These mesoporous HY\nzeolites exhibited high activity and good stability for the isoamylene\ndimerization compared with untreated HY zeolite. Powder XRD patterns,\nN<sub>2</sub> physisorption, SEM, TEM, NMR, FTIR, and NH<sub>3</sub>-TPD techniques were used to characterize the porosity and acidity\nof the zeolites. These results showed that mass transfer and accessibility\nto the acid sites of the guest molecules are the key factors for the\nimprovement of catalytic performances.