SELECTIVE REDUCTION OF DIPHENYLDISULFIDES CATALYZED BY SULFIDES - INFLUENCE OF THE NATURE OF THE CATALYST

The catalytic activities of a series of sulfide catalysts have been examined for the reduction of diphenyldisulfide into benzenethiol. This reaction was studied in a gas-liquid-solid batch reactor. The first step of this study was devoted to the hydrodynamic of the reactor in order to ensure that the reaction proceeds under chemical control. The catalytic activities of the various catalysts vary in a wide range, the most efficient being one of the industrial hydrotreating catalyst tested, i.e., a NiMo/Al2O3. Whatever the nature of the active phase, the reaction was 100% selective toward the formation of benzenethiol. The effects of reducing pretreatments on the catalytic activities as well as the results of TPR and TPD studies suggest reaction mechanism in which M-H (M = transition metal ion) and SH groups intervene simultaneously. © 1993 Academic Press, Inc.