Characterization of used alkaline batteries powder and analysis of zinc recovery by acid leaching

This paper discusses the spent alkaline batteries characterization and leaching stage experiments results with sulfuric acid as leachant, as part of a complex system, involving purification and electrolytic stages, aiming the Zn recovery. After dismantling batteries by mineral processing techniques, the black powder sample produced was submitted to X-ray diffraction and atomic absorption spectrophotometry in order to identify its composition. Batch laboratory experiments were conducted for acid leaching procedure to determine appropriate leaching conditions from the viewpoint of maximum zinc extraction. On these tests an amount of dry powder was added to sulfuric acid at different conditions and after leaching and filtration, the aqueous solutions were submitted to atomic absorption spectrophotometry analysis to verify the Zn content.