Copper-nickel sulfide ores are one of the main sources of platinum. One of
the ways to extract precious metals from such ores involves melting of a
concentrate in electric ore smelting furnaces, where the melt is divided
into matte and slag. Platinum is generally concentrated in matte; however,
some its part remains in the slag, thus leading to metal losses. In order to
reduce platinum losses, the forms of platinum in these phases should be
studied. It was found that during the melting of this ore, iron, nickel, and
copper are reduced. The mineral composition of matte has been studied.
Platinum in matte is present in the form of intermetallics with Fe and Ni.
The PtFe intermetallic is a dispersed needle formation with a length of 20
to 500 ?m and a thickness of up to 10 ?m. The size effect is revealed: the
content of platinum in the PtFe intermetallic decreases with decreasing the
thickness of needle formations. The decreases in the content of platinum in
dispersed needle formations can be explained by an increase in the
thermodynamic activity and changing properties of the dispersed substance
and a corresponding increase in solubility. It was found that matte drops,
together with their associated platinum-containing particles of no more than
5-7 ?m in size, were carried into the slag by gas bubbles using flotation.
The conditions for the rise of a matte drop, together with a bubble in the
slag, consist in the fact that the adhesive force of the drop with the
bubble and the buoyancy force acting on the bubble must be greater than the
gravity of the drop.
Effect of Silver Ions on Bacterial Leaching of Flotation Concentrate of Copper-Nickel Sulfide Ores.
