Si-Sn-MCM-41 (Si/Sn = 110) mesoporous molecular sieve was synthesized by hydrothermal sol-gel method using cetyltrimethylammonium bromide (CTAB) as surfactant and SnCl4 center dot 5H(2)O as a metal source. To generate surface acidity of Si-Sn-MCM-41, 12-tungstophosphoric acid (HPWA) is impregnated on it. The acidity of HPWA loading on Sn-MCM-41 was investigated by temperature programmed desorption of NH3. The diffused reflectance spectra of ultraviolet radiation, Raman spectra, FT-IR, Si-29-MAS NMR and P-31-MAS NMR techniques revealed the intact of alpha-Keggin anions on Sn-MCM-41. The wide angle XRD results showed that the HPWA is well dispersed on the support. The total acidity was enhanced with increase in loading of H3PW12O40. The catalytic activity was examined in desulfurization of dibenzothiophene in vapor phase system. Among the catalysts 18% HPWA loaded Sn-MCM-41 showed good catalytic activity in desulfurization at 325 degrees C. The HPWA/Sn-MCM-41 are a suitable solid acid catalyst for converting organic sulfur into insoluble sulfone. (C) 2014 Elsevier Ltd. All rights reserved.