Desulfurization of model diesel fuel via γAl2O3 and Ni/γAl2O3 adsorbents and determination of their adsorption isotherms

In this work, adsorption of 4,6-dimethyldibenzotiophene (4,6-DMDBT) on Al2O3 and Ni/Al2O3 adsorbents from model diesel fuel (n-hexane-4,6-DMDBT) was investigated in the batch system. At the first, the best alumina selected between 4 type of commercial alumina by adsorption process in the batch system, and then for enhance the adsorption capacity of alumina its surface modified with different percentage of nickel by wetness impregnation method. All adsorption experiments studied in batch systems and equilibrium data obtain after 24 hours in each system. For determination of adsorption capacity, UV-visible spectroscopy used and for characterization of adsorbents, we used XRD, XRF and nitrogen adsorption-desorption analyses. The results indicated that the highest adsorption capacity obtain when 0.15 gram of nickel load on 1 gram alumina (0.15gr Ni/gr Al2O3). Adsorption equilibrium data fitted with Langmuir, Freundlich and Dubinin-Radushkevich isotherms and Langmuir isotherm best described this adsorption process and predicted maximum adsorption capacity 1.253 and 15.97 mg/g for Al2O3 and Ni/Al2O3 respectively.