The potential of mesoporous silica-alumina (MSA) modified by acid leaching as alternative support for Pt catalysts was studied in hydrodesulfurization (HDS) of thiophene and benzothiophene The supports were characterized by N-2 adsorption XRD (27)AL MAS NMR electron microscopy (SEM HRTEM) and by activities in cyclohexene isomerization and cumene cracking The composition of the catalysts and Pt dispersion were determined by ICP and H-2 or CO sorption respectively Progressive leaching of the parent MSA from 50% Al2O3 to 11% Al2O3 content led to increase of the BET surface area and exposition of strong acidity This positively affected the activities of the reduced Pt catalysts in thiophene HDS Deposition of 1 5 wt % Pt on MSA (11% Al2O3) by using Pt(NH3)(4)(OH)(2) as precursor gave the best catalyst several times more active in thiophene HDS than the weight equivalents of sulfided CoMo/Al2O3 or reduced Pt/HY zeolite In benzothiophene reaction its activity was slightly above that of CoMo/Al2O3 and about twofold compared to Pt/HY (C) 2010 Elsevier B V All rights reserved