Effect of hydrochlorination and hydrofluorination of Pt/H-ZSM-5 and Pt–Ir/H-ZSM-5 catalysts for n-hexane hydroconversion

Pt/H-ZSM-5 and Pt–Ir/H-ZSM-5 catalysts were hydrochlorinated or hydrofluorinated with 3.0 wt%HCl or HF, respectively. These mono- and bimetallic catalysts were tested for n-hexane hydroconversion in a pulsed microcatalytic reactor in a flow of H2 gas. The catalysts were characterized via XRD, metal dispersion via H2 chemisorption and acid site strength distribution using temperature programmed desorption of ammonia (TPD). Although metallic promoters frequently cause inhibition of the catalytic activities of Pt and since iridium is less active than platinum, fortunately, Ir was found to enhance the hydroconversion activities of the current catalysts, particularly after hydrochlorination.

Pt and Pt–Ir/H-ZSM-5 catalysts doped with HCl or HF were used to produce iso-C6 and benzene from n-C6. HCl was enhancing, but HF was inhibiting.Figure optionsDownload as PowerPoint slide