BIOLEACHING OF ORES FROM NEUQUÉN ARGENTINA USING A PERCOLATION COLUMN

CHIACCHIARINI PATRICIA; LAVALLE LAURA; DONATI EDGARDO

Ouro Preto Brasil

Congreso; XII ENTMME / VII MSHMT; 2007

The aim of this work was to evaluate the efficiency of the bioleaching of two zinc low grade ores from Cerro Yeguas Vetas and Sofía mine, in the province of Neuquén, Argentina. Pure and mixed cultures of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans were used. Bioleaching experiments were carried out at 30°C in glass columns with the percolation of the medium through the ores. The 9K medium without iron at initial pH 1.8 was used. The particle size of ore samples was between 1.19 and 2.00 mm. Solubilized zinc was determined by atomic absorption spectrophotometry while bacterial populations in solution were evaluated using a Petroff-Haüsser counting chamber in a phase contrast microscope. Metal recovery was significantly enhanced by inoculation. The highest percentages of zinc leached for both ores were reached in the systems where mixed cultures were used.