Process for waste treatment

Organic sulphides are extremely malodorous compounds that are found in gaseous or aqueous effluents from many industries such as paper and pulp manufacture, hydrocarbon refinering, tanneries, and in the synthesis of organic sulphur compounds. Their removal is necessary before such effluents can be discharged into the environment. In the present invention their removal is effected using hydrogen peroxide at a pH controlled to pH 8.5 to 11.5 and in the presence of a catalytic amount of a soluble tungstate. Such a process is especially applicable to the removal of dialkyl disulphides, which are regarded as being especially difficult to remove oxidatively. In especially preferred conditions, the pH is about pH 11 and about 3-4 moles H2O2 is used per mole equivalent of sulphur, in the presence of at least 20 ppm sodium tungstate (as W).