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

摘要

The kinetics of guaiacol conversion over ReS2/SiO2 and ReOx/SiO2 catalysts in a batch reactor at 300 degrees C and 5 MPa hydrogen pressure was studied. The ReOx/SiO2 catalyst was more active and selective towards deoxygenated products (mainly cyclohexane), while the ReS2/SiO2 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/SiO2 and ReS2/SiO2 catalysts. The results for the guaiacol conversion over ReS2/SiO2 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/SiO2 catalyst was fitted to a model that assumes hydrogen adsorption via homolytic dissociation and a single catalytic site. (C) 2015 Elsevier B.V. All rights reserved.