Process for the manufacture of dimethyl disulphide

Process for the manufacture of dimethyl disulphide from methyl mercaptan and sulphur, comprising:

• (a) reacting methyl mercaptan and sulphur in a first reaction zone maintained at a pressure not above 50 bars but sufficient to maintain the methyl mercaptan in the liquid state, wherein the methyl mercaptan and sulphur are introduced in an excess of methyl mercaptan such that the methyl mercaptan/sulphur ratio is between 3 and 6 to selectively produce dimethyl disulphide and minimize methyl mercaptan recycling, and wherein said methyl mercaptan and sulphur are reacted at an elevated temperature in the presence of a catalyst that oxidizes mercaptans with sulphur,
• (b) treating products originating from the first reaction zone in a degassing zone, said products comprising dimethyl polysulphides, to selectively remove at least partially the dissolved hydrogen sulphide, wherein at least 50% of the hydrogen sulphide is removed, and
• (c) bringing the products originating from the degassing zone into contact with a catalyst in a second reaction zone to convert the dimethyl polysulphides with the excess methyl mercaptan.