Selective synthesis of 3-isopropylindole over modified HY zeolites

Abstract

The vapor-phase alkylation of indole with 2-propanol was carried out over HZSM-5 (30), HY, CuHY, CrHY, LaHY and CeHY zeolites at 300 °C with 0.5 h−1 weight hourly space velocity. The catalytic activity with respect to the yield of 3-isopropylindole followed the order: HZSM-5 (30)<CuHY<HY<CrHY<LaHY<CeHY. The various reaction parameters like effect of temperature, weight hourly space velocity and time on stream have been studied. The maximum yield of 3-isopropylindole of 40.0% at a conversion of 63.0% indole was obtained over 3 wt% CeHY zeolite at 300 °C with 0.5 h−1 weight hourly space velocity. The catalysts are characterized by XRD, BET surface area and STPD of ammonia.