An improved desulfurization process based on H2O2/formic acid oxidation system followed by liquid-liquid extraction.: part 1.: Coker gas oil feedstocks

An improved desulfurization process for CGO (coker gas oil) has been investigated on the basis of the oxidation of sulfur compounds by using hydrogen peroxide and formic acid as oxidation reagents. Thiophenic sulfur in CGO was determined via that thioethers could be oxidized to sulfones with KIO3 in acidic medium and LC (liquid chromatography) method. Aiming at reducing the wasteful decomposition of hydrogen peroxide in the selective oxidation desulfurization H2O2/formic acid system, some additives used in the paper or pulp industry, including EDTA, sodium silicate, and magnesium silicate, were used to improve the oxidative efficiency. The following extraction results of oxidized CGO used DMF, furfural, and NMP as solvent showed that EDTA could stabilize desulfurization liquors by complexing transition metals that catalyze hydrogen peroxide decomposition, thus making oxidation and extraction processes more effective.