Chromium (VI) Removal in Packed-Column Microcosm Reactors

This research forms part of the project in which an in situ bioremediation process is being developed to contain Cr(VI) pollution at a contaminated site in Brits, South Africa. The project addresses the need to develop cleanup technologies for chromium-6 contaminated sites in South Africa. The target of the study is to apply an in situ bioremediation process using indigenous bacteria capable of reducing Cr(VI) to remediate or prevent the spread of Cr(VI) into groundwater aquifers in the region. The remediation process was observed in aquifer microcosms in which near 93% of 50 mg/L hexavalent chromium was removed in 45 days of reactor operation. Microbial culture characterisation results showed a change in culture composition after 45 days of reactor operation, indicating Bacillus and Enterobacter species as the most dominant species in reactors that reduced Cr (VI). The outcome of the study will provide an environmentally friendly solution for rehabilitation of Cr (VI) contaminated sites in South Africa. This will be beneficial to SA as SA is the leading chromium ore exporter.