Studies on Indian Ocean manganese nodules .4. Adsorption of some bivalent heavy metal ions onto ferromanganese nodules

The adsorption behavior of M(2+) ions (M = Cu, Co, Ni, and Pb) onto manganese nodules has been investigated at 3.5 less than or equal to pH less than or equal to 5,6 (acetate-acetic acid buffer) and 30 less than or equal to T (degrees C) less than or equal to 50. Under identical conditions the adsorption capacity for different metal ions increased in the order Ni2+ < CO2+ < Cu2+ < Pb2+. In all cases the extent of adsorption increased with increasing pH and temperature. The behavior of various metal ions released from manganese nodules during adsorption has also been discussed,(C) 1996 Academic Press, Inc.