sulfuration

CONT: Activation des minéraux sulfurés oxydés. [...] Les minéraux oxydés de plomb, zinc et cuivre sont difficiles à flotter. [...] En général, on transforme la surface du minéral oxydé en sulfure par action du sulfure de sodium. Parfois, on nettoie les surfaces avant la sulfuration pour éviter de fortes consommations en sulfure de sodium. Après sulfuration, les thiosels comme les xanthates ont une action collectrice satisfaisante.

CONT: Soluble sulphides are often used as activators in the conditioning of oxidised sulphide surfaces. They can also act as depressants if added in excess. ... The metal-sulphide layer at the oxidised mineral surface, so long as it can be sustained, is available for the attraction of xanthate and flotation of the particle bearing this sulphidised surface. ... The durability of the sulphidization by the added S [valence of negative 2] ions is determined by its depth, and therefore by the rate of diffusion into the surface during conditioning.