The adsorption behavior of heavy metal ions such as Cu, Pb, Zn, Cd, Co, and Ni, which exist as a cation, and arsenous acid on deep sea manganese nodules, were studied for the recovery of the metal ions contained in waste waters from the mines. It was observed that heavy metal ions were well adsorbed on the nodules at moderately low pH, provided the reaction is given sufficient time, though the adsorption of arsenous acid is low. The order of activities of the ions for adsorption was: Pb>Cu, Cd>Zn>Ni>Co>>As. The chemical compositions and mineral compositions of the nodules show scarecely effects on the adsorption of heavy metal ions. However, the nodule which is relatively rich in Fe and Co, adsorbs larger amount of As than that which is more abundant in Mn, Ni, and Cu and is composedof 10 Å manganite.
