Kinetic study of the conversion of 2-methoxyphenol over supported Re catalysts: Sulfide and oxide state

Abstract The kinetics of guaiacol conversion over ReS 2 /SiO 2 and ReOx/SiO 2 catalysts in a batch reactor at 300 °C and 5 MPa hydrogen pressure was studied. The ReOx/SiO 2 catalyst was more active and selective towards deoxygenated products (mainly cyclohexane), while the ReS 2 /SiO 2 catalyst was more selective towards the formation of phenol. Langmuir–Hinshelwood kinetic models were developed in order to identify changes in the reaction mechanism with the ReOx/SiO 2 and ReS 2 /SiO 2 catalysts. The results for the guaiacol conversion over ReS 2 /SiO 2 catalyst were fitted to a model that assumes the presence of two different kinds of active sites and that hydrogen adsorption is generated through heterolytic dissociation. The conversion of guaiacol over the ReOx/SiO 2 catalyst was fitted to a model that assumes hydrogen adsorption via homolytic dissociation and a single catalytic site.