STUDY ON THE PREPARATION OF ZINC SULFATE FROM CHLORIDE- CONTAINING HOT DIP GALVANIZING ASH

Abstract

This study aimed to develop a zinc sulfate preparation process from
chloride-containing zinc ash formed during the hot dip galvanizing. Zinc sulfate
solution was formed by the hydrometallurgy of zinc ash in sulfuric acid. The main
impurities included in the solution such as iron and aluminum were removed by
pH-controlled precipitation using 10% NaOH solution as a neutralizing agent. In
order to remove chloride, copper (I) oxide was used. The results showed that the
hydrometallurgy of zinc ash achieved the highest yield (98.05% zinc was
extracted) under the conditions: sulfuric acid concentration of 2 M, temperature
of 55oC, liquid to solid ratio of 8/1 and leaching time of 90 min. Zinc sulfate with
the purity of 98.37% was crystallized from refined - zinc sulfate solution.