Study of a pilot plant for the recovery of metals from spent alkaline and zinc-carbon batteries with biological sulphuric acid and polythionate production

FALCÓ, L.; MARTINEZ, A.; DI NANNO, P.; THOMAS, H.; CURUTCHET, G.

LATIN AMERICAN APPLIED RESEARCH

PLAPIQUI(UNS-CONICET)

Lugar: Bahia Blanca; Año: 2014 vol. 44 p. 123 - 130

0327-0793

recovery of Zn and Mn fromspent alkaline and Zn-C batteries with a biohydrometallurgycalprocess was studied in a pilot plantthat consists of an air-lift bioreactor with a sulphurpacked bed where Acidithiobacillus thiooxidans producesan acid-reducing medium; a leaching reactorwhere the acid-reducing medium is mixed with thebattery powder, and a recovery reactor where metalsare recovered from the leaching liquor by electrolysis.Results show that with acid medium (350mM[H+]) produced in 12 days by Acidithiobacillusthiooxidans in the bioreactor, an extraction of 100%of Zn and 67% of the Mn present in the batterypowder was reached. The presence of polythionatesin the medium produced in the bioreactor allows thedissolution of the manganese. The solid remainingafter bioleaching is a manganese oxide. The electrolysisof the leaching liquor produced a cathodicdeposit of metallic Zn and an anodic deposit of amanganese oxide