Bioleaching of shale – impact of carbon source

Abstract

Bioleaching is often used for processing low-grade shale feedstock and the microbial community used for that purpose is supplied with nutrients such as sugar and/or Fe2+. In the present study, the leaching efficiency was tested when crushed weathered shale was mixed with aspen wood shavings and kept moist, at the mixtures field capacity. The purpose was to investigate whether a more complex carbon source and a lower content of water may be a feasible way of lowering the cost for bioleaching. After 56 days of incubation the amount of uranium mobilized from the shale reached some 1.7% with a minimum of effort and cost.