Separation of pyrites arsenopyrite and pyrrhotite by flotation

摘要

Pyrites is separated from arsenopyrite by subjecting a mixture of them to conditioning with sufficient alkali metal permanganate to depress the arsenopyrite and then subjecting the conditioned material to froth flotation in the presence of a promoter for pyrites so that a concentrate is obtained which is rich in pyrites and a tailing rich in arsenopyrite. If the mixture also contains pyrrhotite, it is first conditioned by the addition of a small amount of permanganate sufficient to depress the pyrrhotite but not the arsenopyrite. The conditioner material is then subjected to froth flotation in the presence of a sulphide promoter to obtain a concentrate rich in pyrites and arsenopyrite and a tailing containing most of the pyrrhotite. The concentrate is then treated with an additional amount of permanganate sufficient to depress the arsenopyrite and is then subjected to froth flotation in the presence of a sulphide collector so that a concentrate rich in pyrites is obtained and a tailing containing the arsenopyrite. In both processes the flotation takes place in the presence of a collector containing the dithiophosphoric acid radical, xanthates and mercaptobenzothiazole.