Studies on adsorptive desulfurization by zirconia based adsorbents

This study reports usage of laboratory prepared zirconia samples (normal dried zirconia (ZD383), zirconia calcined at 893 K (ZC893), zirconia sulfated and calcined at 893 K (SZC893)) as adsorbents for the removal of sulfur from model oil (dibenzothiophene, DBT in iso-octane). Bulk densities of adsorbents were found to be in the range of 0.896–0.987 kg/m3. Optimum adsorbent dose was found to be 10 g/l. The adsorption of DBT on zirconia based adsorbents was found to be gradual process with quasi-equilibrium condition reached in 22 h. Brunauer–Emmett–Teller (BET) isotherm best represented the equilibrium adsorption data. The heat of adsorption and change in entropy for DBT adsorption onto zirconia based adsorbents were found to be −165.3 (ZD383), −125.5 (ZC893), −96.7 (SZC893) kJ/mol, and −509.9 (ZD383), −379.4 (ZC893), −284.1 (SZC893) J/mol K, respectively.