Biological Reduction of Radionuclides under Facultative Anaerobic Conditions using Radiation Tolerent Consortium

The release of uranium and its decay products from various industries to the environment has been a subject of major concern worldwide. In this study the removal of U(VI) from the aqueous solution was evaluated using facultative anaerobes isolated from the abandoned uranium mine in Phalaborwa, South Africa. This species were able to reduce U(VI) to U(IV) in the presence of nitrate (NO3−), the common co-pollutant existing in the nuclear waste. The removal efficiency of about (80-100%) observed in batch studies at the initial U(VI) concentration up to 400 mg/L under near neutral pH and ambient temperature. Mass balance analysis of uranium species inside and around the cell membrane aided by transmission electronic microscope (TEM) confirmed extracellular U(VI) reduction-precipitation. This finding indicates the possibility easy uranium recovery for commercial purpose and for restoring the site through a biological remediation process.