Hydrometallurgical method for recovery of zinc in sulphuric medium starting from sulphidic zinc concentrates with high iron content

摘要

#$%^&*AU2012350339B220160331.pdf#####ABSTRACT HYDROMETALLURGICAL METHOD FOR RECOVERY OF ZINC IN SULPHURIC MEDIUM STARTING FROM SULPHIDIC ZINC CONCENTRATES WITH HIGH IRON CONTENT 5 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: 10 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 15 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. 20