Bioremediacion de un suelo contaminado con cromo y recuperacion del metal por tecnicas biohidrometalurgicas con monitoreo por bioensayos

SUSANA ESPINOSA, PÍA DI NANNO, CRISTINA PEREZ-COLL Y GUSTAVO CURUTCHET.

Salud Ambiental y Humana: Una Visión Holística

SETAC

Lugar: Buenos Aires; Año: 2006; p. 147 - 149

Abstract Biohydrometallurgical techniques for metal recovery are very well known in the mining industry. Nowadays various commercial plants for gold, copper, cobalt and other metals recovery are operated worldwide.  In almost all the cases these industries use the oxidative metabolism of Acidithiobacillus and other acidophillic bacteria, autotrophs and very resistant to high heavy metal concentrations. These bacteria obtain energy from reduced sulphur compounds and ferrous iron oxidation and generate acid media with different redox properties. These acid media are used to mobilize or immobilize metals. In this work different bioleaching conditions were assayed with the aim to recover chromium from a heavy polluted soil from an abandoned tannery in Quilmes, Buenos Aires province, Argentina. Pneumatically aerated systems were used, inoculated with Acidithiobacillus thiooxidans or Acidithiobacillus ferrooxidans –with or without alternative electron sources like elemental sulphur- and the kinetics of chromium extraction were analyzed. Also chromium(III) toxicity was evaluated using a standard bioassay with Bufo arenarum embryos (ANFITOX). The results obtained demonstrate an interesting chromium leaching from the soil. This chromium is recoverable from the leachate and the soil after the treatment has less toxic properties due to the chromium removal.