Abstract:

The recovery of Zn and Mn from spent alkaline and Zn-C batteries with a biohydro-metallurgycal process was studied in a pilot plant that consists in an air lift bio-reactor with a sulfur packed bed where Acidithiobacillus thiooxidans produces an acid-reducing medium; a leaching reactor where the acid-reducing medium is mixed with the battery powder and a recovery reactor where metals are recovered from the leaching liquor by electroly-sis. Results shows that with a 350 mM in proton me-dium produced in 12 days by Acidithiobacillus thiooxidans in the bio-reactor, an extraction of the 100% of Zn and 67% of the Mn present in the bat-tery powder was reached. The presence of polithionates in the medium produced in the bio-reactor allows the dissolution of the manganese. The solid remaining after bioleaching is a manganese oxide. The electrolysis of the leaching liquor pro-duced a cathodic deposit of metallic Zn and an an-odic deposit of a high surphase manganese oxide in one step at room temperature.

Author affiliation: Thomas, Horacio Jorge. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Planta Piloto Multiproposito; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina

Author affiliation: Falco, Maria Lorena Romina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Planta Piloto Multiproposito; Argentina

Author affiliation: Di Nanno, Maria Pia. Universidad Nacional de San Martin. Instituto de Inv. E Ingenieria Ambiental. Cent.de Estudios Ambientales; Argentina

Author affiliation: Martinez, Analia Beatriz Luján. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Planta Piloto Multiproposito; Argentina

Author affiliation: Curutchet, Gustavo Andres. Universidad Nacional de San Martin. Instituto de Investigaciones e Ingenieria Ambiental. Cent.de Estudios Ambientales; Argentina