HYDROMETALLURGICAL METHOD FOR RECOVERY OF ZINC IN SULPHURIC MEDIUM STARTING FROM SULPHIDIC ZINC CONCENTRATES WITH HIGH IRON CONTENT

摘要

This method is based in the recirculation of an iron free solution or a solution with low iron content in such a manner that the final acidity conditions obtained are ideal for iron to efficiently precipitate as jarosite.;In a variation of the invention the zinc concentrate is subjected to the following stages:
a. Roasting of at least part of the zinc concentrate.b. Neutral leaching where zinc oxide is dissolved.c. Acid leaching where zinc ferrites are leached.d. Reduction of the Fe+++ contained in the solution to Fe++ by adding zinc concentrate and diluting it with a zinc sulphate solution resulting from stage (f) to lower the concentration of Fe++.e. Neutralizing the acidity in the solution with calcine.h. Iron oxidation and jarosite precipitation, free of contaminating solids, by means of the injection of oxygen or oxygen-enriched air and the addition of an alkali or a Na+ o NH4+ salt.