Effect of Fe-Ions on Pyrite-Xanthate Interaction in Chemically Manipulated Electrochemical Conditions

Abstract

The effect of ferrous and ferric ions on pyrite-xanthate interaction was investigated with contact angle
measurements and UV-visible spectroscopy studies. Experimental works were conducted in chemically manipulated
electrochemical conditions between 0-500 mV potential ranges. KMnO4 and Na2S2O5 were used to manipulate potential
as oxidizing and reducing agents, respectively. Xanthate improved hydrophobicity of pyrite due to coverage of mineral
surface with dixanthogen, but the contact angle decreased with the addition of ferrous and ferric ions. Pyrite displayed
hydrophobic property in mild to moderately oxidizing conditions, whereas lower contact angle values were obtained at
higher potentials due to the increase in the number of hydrophilic sites on the surface both in the absence and presence of
xanthate and Fe-ions. UV spectroscopy study and contact angle measurements proposed that although the ferric hydroxy
xanthate complex species could form at highly oxidizing potentials, the main hydrophilic species inhibiting the collector
adsorption would be ferric oxyhydroxides in pyrite-xanthate system in the presence of ferric and ferrous ions.