Radioisotopic study of CoMo/Al2O3 sulfide catalysts for HDS: Part II. Temperature effects Original Research Article

Using 35S, reaction temperature effects within the range of 300–400 °C on the number and reactivity of active sites of sulfidized Mo/A2O3 catalysts (non-) promoted by Co in thiophene hydrodesulfurization (HDS) have been studied. On the basis of the results of the radioisotopic tests of the catalysts, changes in the number and mobility of the surface SH groups, as well as relationships between them and the coordinatively unsaturated sites (CUS) have been evaluated. Estimated dependencies have been explained in the terms of the “forcing out” mechanism.