A method of sweetening of lpg, light petroleum distillates by liquid - liquid - extraction under use of a metal phthalocyanine sulfone amide - catalyst, comprising extracting the in lpg, light petroleum distillates mercaptans contained by liquid - liquid - extraction under the use of an aqueous or alcoholic solution of an alkali metal hydroxide a concentration in the range from 1 – 50 w -% of the alkali metal hydroxide in the aqueous or alcoholic solution, in the presence of a metal phthalocyanine sulfone amide - catalyst in the concentration range of 5 – 4000 ppm (weight), based on the alkali solution, at a temperature in the range of 10 – 80°C. in the case of a pressure in the range from 1 – 50 kg / cm2 in a continuous or discontinuous manner, the conversion of the in the above extract existing mercaptans in the corresponding disulfides by passing air, oxygen or an oxygen-containing gas in the above temperature and the above pressure, and the regeneration of the alkali solution containing the catalyst by separating off the upper layer of disulfides of the alkali solution of the catalyst.