The rate of leaching of iron from ilmenite (FeTiO 3 ) in hydrochloric acid (HCl) solutions is greatly enhanced by the presence of ultraviolet (UV) light. The magnitude of the air purged UV light illuminated leaching rate is approximately twofold higher than the N 2 purged leaching rate under dark conditions. The enhanced rate is attributed to the photo dissociation of polymeric titanium oxy species via oxidising radicals OH and HO 2 formed through Fe 3z /Fe 2z /H 2 O Fenton type reactions. Photo dissociation and consequent non-deposition of polymer species in the pores of ilmenite particles cause the chemical reaction between FeTiO 3 and HCl acid in stirred solutions to become the rate determining step. The addition of H 2 O 2 to the reaction mixture, in the presence and absence of UV light, further enhances iron leaching rate, confirming the role of radical species.

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