The effect of the alkyl chain length and ligand type of thiol collectors on the heat of adsorption and floatability of sulphide minerals

Both the heat of adsorption and microflotation recoveries increased with increasing collector chain length for xanthate homologues on all mineral types. There was a positive linear correlation between the heats of adsorption and microflotation recoveries. However, this relationship was not sustained for collectors with different ligand types. The heat of adsorption of diethyl-DTC was always higher than that of diethyl-DTP for all the minerals. In fact, diethyl-DTP barely interacted with any of the sulphide minerals although it produced unexpectedly high chalcopyrite recoveries. It was found that the heat of adsorption is not a robust indicator of hydrophobicity for collectors of different ligand types. However, for collectors of the same ligand type, but differing alkyl chain lengths, it is a strong predictor of hydrophobicity.