Pt/H-ZSM-5 and Pt-Ir/H-ZSM-5 catalysts were hydrochlormated 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 H-2 gas. The catalysts were characterized via XRD, metal dispersion via H-2 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. (c) 2007 Elsevier B.V. All rights reserved.