The ion exchange of trace amounts of Cu2+, Zn2+and Pb2+with the hydrogen-form of hydrated ferric oxide as a function of nitric acid concentration has been studied at 25, 30,35 and 60°C. Ion exchange of these cations increases with increasing temperature in the investigated temperature range. From these results, equilibrium constants for the Cu2+/H+, Zn2+/H+and Pb2+/H+ion exchange on hydrated ferric oxide and thermodynamic quantities for these reactions were calculated, and some predictions made for the exchange process taking place in this material. The selectivity series is Zn2+> Cu2+> Pb2+.