The present invention related to a process for sweetening of LPG light petroleum distillates by liquid liquid extraction using metal phtalocyanine sulphonamide catalyst which comprises extracting the mercaptanes contain in LPG, light petroleum distillate like pentanes, light straight run naphtha by liquid-liquid extraction using an aqueous or alcoholic solution of alkali metal hydroxide of concentration ranging between 1 wt % to 50 wt % in the presence of a metal phthalocyanine sulphonamide catalyst in the concentration ranging from 5-4000 ppmw, at a temperature ranging from 10° C. to 80° C. at a pressure ranging from 1 kg/cm2-50 kg/cm2 in a continuous or batch manner, converting the mercaptanes present in above said extract into corresponding disulphides by passing air, oxygen or any oxygen containing gas at the above same temperature and pressure, regenerating the alkali solution containing catalyst for recycling by separating the upper layer of disulphides from said alkali solution of catalyst.