ABSTRACT
In parallel the increasing success of application of bioleaching in hydrometallurgy and mining, microorganisms involved in bioleaching have been investigated for potential application in other fields. The sediment is a polyphasic environmental matrix that forms by natural sedimentation of particulate materials within the water column, which in turn, originate by a variety of different natural processes: e.g., erosion, transport by rivers, deposition of organic particles, weathering of primary minerals, mineral (bio-)precipitation. Metals and semi-metals can enter a water body as a result of multiple processes such as atmospheric deposition, erosion of the bed-rock minerals as well as intake by a variety of anthropic activities. Sediment bioleaching is usually investigated as the bio-augmentation with selected microorganisms or consortia with specific key biogeochemical functions. A variety of heterotrophic acidophiles have been isolated from the same environment as Fe/S oxidizers. Some have been already reported to favor bioleaching processes. pH is one of the most important variables that influence (semi-)metal bioleaching from solids.
