Thermoacidophilic bioreduction of elemental sulfur for the recovery of valuable metals

Metallurgy operations produce hot, acidic waste streams that still contain high concentrations of valuable metals. These metals can be recovered through their selective precipitation with sulfide as metal sulfides (MeS).

In situ microbial sulfidogenesis is economically and environmentally more attractive than physicochemical methods, but for the treatment of hot, acidic metalliferous waters this requires microbial sulfidogenic communities thriving at high temperature and low pH. This project will therefore study the ecophysiology and microbiology of acidothermophilic elemental sulfur (S0) reducers, with the aim to (1) improve our fundamental understanding of S0 respiration at these extreme conditions; and (2) contribute to the development of metal recovery technologies based on in situ sulfidogenesis.

Thermoacidophilic elemental sulfur (S0) reducers are microorganisms living in hot, acidic environments such as volcanic hot pools that obtain energy through anaerobic respiration with S0, resulting in the production of hydrogen sulfide (H2S). Although the diversity and abundance of these microbes in such environments indicate that this process plays an important role in the sulfur cycle, knowledge about these organisms is relatively scarce. I therefore study their physiology in more detail, and am particularly interested in the mechanisms for interaction with S0 particles.

Student projects

Are you interested in the physiology of extremophiles and their potential applications in biotechnology, and would you like to discuss opportunities to do your BSc. or MSc. thesis project on this topic? Send me an email or drop by my office.