Microbiological Advances in Biohydrometallurgy

Abstract

The most exciting advances in biohydrometallurgy are occurring in the field of microbiology. The two main technologies employed in biohydrometallurgy, agitated tanks for the processing of refractory concentrates and heaps and dumps for the processing of low-grade ores, are technologically sound and widely practised at commercial scale, but their development began at a time when very little was known of the microorganisms that assisted metals extraction from sulfide ores. During and subsequent to those developments it has been shown that microbial communities in metals extraction are more diverse than originally thought, and extremely robust and adaptable to different and variable environments. Recent advances in genomics and proteomics, exploiting hugely increased computing power and speed, have made it possible to describe not only which microorganisms are present in bioleaching systems, but also what physiological functions are being exercised. The body of knowledge being acquired through the application of molecular biology methods will be used increasingly to monitor microbial behaviour, optimise conditions for more appropriate microbiological activity and/or infer the "microbiological health" of bioreactors (tanks and heaps).

Desulfurization of Iron Ores: Processes and Challenges

“…The principal acid‐generating microorganism affiliated with mineral leaching is Thiobacillus ferrooxidans , which oxidizes both reduced sulfur and iron compounds in acidic conditions . The perceived importance of A. ferrooxidans in bioleaching environments was largely a consequence of the relative ease of its enrichment and isolation, and its rapid growth in acidic iron(II) media, by which it out‐competed other members of its microbial community . Furthermore A. ferrooxidans is an effective toxin resistant microorganism in bioleaching process.…”

Resource Recovery from Low‐Grade Ore Deposits and Mining Residuals by Biohydrometallurgy and Membrane Technology. Potentials and Case Studies

“…The technical implementation of biohydrometallurgy is mainly realized by heap leaching, stirred tank reactors, and in‐situ leaching . The apllications will be explained in the following section.…”

Biooksidasi: Teknologi Alternatif Pengolahan Bijih Emas Refraktori

“…Mikroorganisme yang paling penting adalah yang bersifat autotrof dan menggunakan karbondioksida sebagai sumber karbon. Walaupun sumber energi bervariasi tergantung jenis mineralnya, mikroorganisme ini tumbuh dengan mengoksidasi ion fero, atau ion sulfur, atau keduanya (Rawlings dan Johnson, 2007;Schippers dkk., 2013;Watling, 2016 (Anonymous, 2008) Semua bakteri kemolitotrof dianggap sebagai bakteri obligat aerob, yaitu membutuhkan oksigen sebagai akseptor elektron atau agen pengoksidasi. Terdapat beberapa bukti bahwa sebagian bakteri kemolitoautotrof, pada kondisi tertentu, menjadi fakultatif aerobik ketika bakteri itu mendapatkan energi dengan menggunakan ion feri sebagai oksidan.…”