| 摘要 |
<p>The invention concerns a method for treating waste stripping solutions to obtain ferrous chloride solutions sufficiently concentrated in whole iron and depleted in zinc and other metal impurities. The method comprises three successive operational steps: a first step for neutralizing the waste stripping acid by reaction between the residual acid consisting essentially of HCl and iron oxides or hydroxides consisting essentially in Fe2O3, Fe3O4, FeOOH, Fe(OH)3; a second step for reducing the ferric iron (Fe3+) present in the bath solutions through metal iron; and a third step for eliminating the heavy metals, in particular Zn?2+, Pb2+, Sn2+, As2+, Cu2+, Co2+, Ni2+, Cd2+¿ in the form of sulphides by precipitation, thereby obtaining a solution for use in economical conditions for producing ferric chloride or in plants purifying waste water or effluents.</p> |
