DESULFURIZATION OF PETROLEUM STOCK

Abstract

The removal of sulfur compounds from petroleum stocks is crucial to producing clean burning fuels. Sulfur compounds poison emission control catalysts and are the source of acid rain. New federal regulations require the removal of sulphur (with maximum sulfur limit of 50 mg/I as per Bharat IV norm) in both gasoline and diesel to very low levels As the oxidative desulfurization is conducted under very mild reaction conditions, much attention has been recently devoted to this process, so ODS can be used to reduce the cost of producing ultra-low sulfur diesel (ULSD). The objective of this thesis is to set up a novel desulfurization technique based on oxidation o DETusing copper oxide impregnated activated alumina and ferrous sulfate. Characterization of catalysts was carried out using standard procedures; scanning electron microscope (SEM), energy dispersive x-ray (EDX), x-ray diffraction (XRD), brunauer-emmett—teller (BET) and tourier transform infrared spectroscopy (1-' /IR). The parameters studied are CuO (wt %) loading on alumina: 5-30 wt%; reaction time (t): 15-120 min; temperature (T): 30-80 °C; and 0/S molar ratio: 10-40. The individual and interactive effects of the above mentioned parameters have been_ studied using Gas Chromatography. Activation energy for DBT oxidation was determined to be 25.45 kJ/mol. The highest removal of DBT was obtained with 15% CuO/A1203 at optimum conditions; t= 90 min, T= 60 °C and 0/S= 30. Copper oxide impregnated alumina was found to give greater removal of sulfur than ferrous sulfate.