Adsorptive desulfurization and denitrogenation of model fuel using HPW and NiO-HPW modified aluminosilicate mesostructures

The performance of the aluminosilicate mesostructure (MSU-S) and its modified forms with phosphotungstic acid (HPW) and nickel oxide-HPW (NiO-HPW) for desulfurization and denitrogenation of model diesel fuels were studied. According to the results of characteristic tests (N-2 adsorption-desorption, XRD, SEM, and NH3-TPD), HPW incorporation causes higher acidity along with a negligible loss in structural aspects, while NiO-HPW impregnation leaves a negative effect on mesoporous structure, crystalline phase, and particle shape along with a high positive impact on surface acidity. With NiO-HPW modification, the maximum increase of 33.18% and 6.88% is occurred for the adsorption loading of total sulfur and total nitrogen, respectively. Both modified adsorbents perform selective towards nitrogen removal over sulfur compounds. The pseudo-second order model can best fit the kinetics data and Freundlich model can best describe the equilibrium isotherm for all species over NiO/HPW-MSU-S. (C) 2015 Elsevier Inc. All rights reserved.