Isopropylation of naphthalene over mordenite zeolites: Effect of Si/Al ratio

Isopropylation of naphthalene with propylene was carried out over mordenite zeolites with various Si/Al ratios in the range of 23 and 112. The reaction was carried out in a fixed-bed reactor at 300 °C, 7 kg/cm², WHSV = 1 h^-1, and the molar ratio of propylene to naphthalene of 6. All mordenite zeolites exhibited significant shape selective properties. The naphthalene conversion decreased with an increase in the Si/Al ratio of the zeolite. Also, the selectivity of 2, 6- and 2, 7-diisopropylnaphthalene (DIPN) in total DIPN increased with an increase in the Si/Al ratio. The compositions of 2, 6-DIPN in total DIPN and the ratios of 2, 6-/2, 7 isomers for all zeolites are far above equilibrium values. Both of them increased with an increase in the Si/Al ratios. The shape selective properties would become more significant with an increase in the Si/Al ratio and the reaction time on stream.