Biomodulation of mineral surfaces for selective separation of pyrite from chalcopyrite: a ftir study

This paper discusses the utility of FTIR spectra in understanding the mechanism of selective separation of chalcopyrite from pyrite after biomodulation using Acidithiobacillus ferrooxidans cells. Consequent to interaction with bacterial cells, pyrite remained depressed even in presence of collector while chalcopyrite exhibited significant flotability. FTIR spectra indicated that the major species formed when pyrite and chalcopyrite were interacted with an aqueous solution of potassium ethyl xanthate was dixanthogen and copper (I)alkyl xanthate respectively. The observed difference in the flotability of the two minerals after interaction with the cells and collector is explained based on FTIR studies