Efficient catalytic oxidative desulfurization of liquid fuels over tungsten oxide supported on metakaolin surface

Abstract A new high yield and inexpensive composite was fabricated by supporting tungsten oxide on metakaolin via the incipient wetness impregnation method to use in oxidative desulfurization reaction and produce ultra‐clean fuel. The prepared catalyst was characterized by various techniques like XRD, FTIR, FESEM, EDX and N 2 adsorption–desorption isotherms, which indicated the catalyst was properly constructed. Initially, desulfurization was examined by loading different amounts of tungsten on the metakaolin surface. Based on the results, 15 % W/metakaolin showed high catalytic activity for the model and real fuels. Moreover, the influence of the main operating variables was studied through the Box–Behnken experimental design. The maximum sulfur removal reached to 99.3 % at a reaction temperature of 60 °C, oxidant to sulfur molar ratio12, catalyst dosage 0.04 g and oxidation time 40 min. Desulfurization from gasoline and gas oil with initial sulfur contents of 300 ppm and 7550 ppm was done under optimum conditions, which represented an efficiency of 60 % and 74 %, respectively. Performing the recycling tests proved the great durability of the catalyst after five runs. This research sheds light that the employed catalyst has excellent activity for industrial applications in the desulfurization process.