Treatment of sugar and amount charcoals, containing different amounts of combined oxygen and hydro­gen, with carbon disulphide or hydrogen sulphide results In appreciable fixation of sulphur, the effect being maximum at 600°. The amount of sulphur fixed decrease with decrease in the hydrogen and oxygen contents of the charcoal. The results Indicate that the fixation of sulphur involves addition at the unsaturated sites and substitution of hydrogen or oxyhydrogen groups present on the charcoal surface.