Prospective directions for biohydrometallurgy

Abstract

Biohydrometallurgy has been commercially applied for the extraction of base metals from low-grade sulfidic ores and the pre-treatment of refractory sulfidic gold-containing minerals. Recent research explores its potential for other types of commodities, such as rare earth elements, and ores found in deep subsurface of the Earth, ocean floor and outer space. The application of biohydrometallurgy for extracting resources from waste streams is also gaining increasing interest to support the move towards a circular economy. The utilisation of complex feedstock is associated with new challenges, which may require the integration of various unit processes that combine biological approaches and/or electrochemistry, with physical or chemical processing. New biolixiviants are also being explored to mitigate harmful environmental impacts. The range of biocatalysts available for biohydrometallurgy can be increased through bioprospecting of novel biomining microbes, increasing the metabolic capability of microbes through adaptive evolution and engineering microbes through synthetic biology. New modelling and artificial intelligence tools are also expanding the opportunities for optimising biotechnical processes. This paper reviews recent trends and prospective directions for biohydrometallurgy.