The oxides formed from chlorinated ferrous solution are designated Fe oxides, while those from chlorinated ferrous mixed with manganese solution are designated Fe–Mn oxides. The chlorinated feed water was continuously pumped into the dead-end MF unit for 30 min at a constant transmembrane pressure (TMP) of 1 kg/cm2. To make up the background ions in natural groundwater, CaCl2 and MgCl2 were simultaneously added into the feed water (i.e., 100 mg/L Ca and 20 mg/L Mg). The pH of the chlorinated feed water before membrane filtration was about 8.