Surface characteristics and flotation behaviour of platinum and palladium arsenides.

Significant PGM losses may occur due to the poor floatability of arsenides of the platinum group elements which contribute around 21% of those present in Platreef ore from the Bushveld Complex, South Africa. The surface characteristics and flotation behaviour were investigated of synthetic sperrylite (PtAs2) and palladoarsenide (Pd2As). The results showed that both can be recovered by flotation in the presence of xanthate alone, and the addition of copper sulphate as activator resulted in a slight decrease in recovery. A sperrylite sample synthesised using a short initial thermal treatment floated well in the presence of xanthate, while a sample synthesised for a longer period floated poorly irrespective of the reagent suite used. The former sample exhibited many Pt blebs while the latter was more homogeneous. The latter sample when crushed to below 38 micrometres showed increased recovery, possibly due to the exposure of the Pt blebs.
Significant PGM losses may occur due to the poor floatability of arsenides of the platinum group elements which contribute around 21% of those present in Platreef ore from the Bushveld Complex, South Africa. The surface characteristics and flotation behaviour were investigated of synthetic sperrylite (PtAs2) and palladoarsenide (Pd2As). The results showed that both can be recovered by flotation in the presence of xanthate alone, and the addition of copper sulphate as activator resulted in a slight decrease in recovery. A sperrylite sample synthesised using a short initial thermal treatment floated well in the presence of xanthate, while a sample synthesised for a longer period floated poorly irrespective of the reagent suite used. The former sample exhibited many Pt blebs while the latter was more homogeneous. The latter sample when crushed to below 38 micrometres showed increased recovery, possibly due to the exposure of the Pt blebs.