Flotation of coal and sulphur from a typical South African ultrafine
colliery waste has been achieved in laboratory-scale batch flotation
tests, using dodecane, kerosene, and oleic acid as coal collectors, and
xanthates to float the sulphide minerals (with the aid of dextrin as a
coal depressant). The use of oleic acid as collector, in conjunction
with MIBC frother, produced a coal yield of 56 per cent (much more
than was obtained with dodecane or kerosene) at an ash content of
18 per cent, from a feed ash of 34.4 per cent; and a low- sulphur
tailings. Sulphide flotation using potassium xanthate (PAX)
recovered 26.3 per cent of the total sulphur in the concentrate.
Staged addition of xanthate increased the total sulphur recovery to
42.1 per cent and reduced the sulphur content of the tailing further