1. Introduction
Fe and Mn are found in groundwater in their most soluble form, Fe(II) and Mn(II) ions, and in the oxide form, Fe2O3 and MnO2. Conventionally, raw water is first oxidized, and then filtered to remove the oxide solids. Vigorous oxidation is needed to comply with discharge regulations. Without oxidation, ferrous and manganese ions can easily escape water treatment processes and continue to oxidize to become insoluble oxides in the distribution system, thus causing water discoloration, metallic taste, odor and turbidity [1]. For these reasons oxidation is an important step in water treatment for Fe and Mn removal.