method for extraction of zinc from zinkferrithaltigen rueckstaenden

摘要

The improvement in the process for recovering zinc from ferrites which includes treating electrolytic zinc plants residues with a sulfuric acid solution to dissolve the zinc and metals, a solution resulting which contains sulphates of zinc and the other dissolved metals. The undissolved residue is separated in a certain manner from the solution. The solids-free solution is neutralized in a second step with calcine or another neutralizing agent containing zinc until a certain acidity is reached so that the iron remaining in solution separates therefrom in the form of its complex basic sulfate. The solids are settled out and then sent to a neutralization step, which is part of the residue separation scheme, where they are used as seeds of crystals of complex basic sulfate of iron which helps to remove iron in the first neutralization step. This final solution is added to the normal circuit or process flow path of electrolytic zinc plants. Any Fe++ existing or forming during the process is oxidized by MnO2.