3. RESULTS AND DISCUSSION
3.1 Cyclic Voltammetry
Figure 1 shows the cyclic voltammetry
result of pentlandite. On the anodic scan, two
oxidation current peaks (A1 and A2) can be
noted, on the cathodic scan, one prominent
cathodic current peak (C1) is present. The peak
A1 starts at about 0 mV and continues in a
wide potential range up to about 300 mV.
This peak is attributed to the following
electrochemical reaction:
(1)
where S0
could also be the metal deficient layer,
and this sulfur-like layer makes the pentlandite
hydrophobic [15, 16], whether the surface
product is element sulfur or metal deficient
layer, which is decided by the extent of
oxidation. When the mineral starts to be
oxidized, the metal ions dissolved from the