Abstract
Zn, Cd and Mn bearing ferrites suspensions were obtained by air oxidation of heavy metal and ferrous hydroxide, Fe2+/M2+ molar ratio in the initial suspensions were 2-32 at initial pH 12 and 60°C. The pH of ferrite suspensions were adjusted to 1-7 and the dissolution of heavy metals from these suspensions was studied. The metal ions corporated into the ferrite are stable at pH 2.5-4.5.
The ferritization of Zn, Cd and Mn ions was estimated by the stability (=1 - the dissolved heavy metal ratio at pH3-3.5.)
The stability in the ferritization linearly increased with aeration time and stopped at completion of Fe2+ oxidation, detected by DO concentration of the suspension. The optimum initial pH was near 12 by considering the effects on final pH in the ferritization, heavy metal ions concentration of treated water and the stability.
