from the conferences organized by TANGER Ltd.
The increasing demand for critical metals required for modern technologies has led to recycling waste or any secondary sources containing valuable metals in the present case germanium. Copper slags are generally rich in iron and silicate phases in form of fayalite, which contains trace metals of germanium, gallium, zinc and other critical elements that can be liberated. Although traditional hydrometallurgical techniques offer quick extraction they are linked to significant high energy consumption, extensive chemical use and secondary pollutants which limits their environmental sustainability and sometimes selectivity might be required. According to the review of research for more than a decade bioleaching has shown more selectivity where viable microorganisms like Acidithiobacillus and Bacillus species. These Bacillus are prone to promote an improve dissolution of phases containing within the iron and silicon compounds, increasing the valuable trace metal amount of germanium release. Research has shown that factors like pH, slurry, concentration, aeration and microbial collaborations affected how well bioleaching will work. Additionally, the strain adaptability and mutagenesis increase extraction yields. Although bioleaching has clear benefits over chemical leaching such as selective solubilisation, reduce energy needs and environmental friendliness the slow kinetics leaching remains a challenge. Research conducted examined selective germanium bioleaching from fayalitic copper slag using Bacillus species. Slag characterization employed XRF, XRD, and SEM. Leaching with oxalic acid and hydrogen peroxide at pH 4-5 achieved optimal recovery at 1.5 M within 30 minutes, with leachates analysed using ICP. These findings highlight the potential of this method for efficient germanium recovery.
Keywords: Bioleaching; copper slag; germanium© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.