Abstract
SummaryThere are a need for novel, economical and efficient metal processing technologies to improve critical metal sustainability, particularly for cobalt and nickel which have extensive applications in low‐carbon energy technologies. Fungal metal biorecovery processes show potential in this regard and the products of recovery are also industrially significant. Here we present a basis for selective biorecovery of Co and Ni oxalates and phosphates using reactive spent Aspergillus niger culture filtrate containing mycogenic oxalate and phosphate solubilized from struvite. Selective precipitation of oxalates was achieved by adjusting phosphate‐laden filtrates to pH 2.5 prior to precipitation. Co recovery at pH 2.5 was high with a maximum of ~96% achieved, while ~60% Ni recovery was achieved, yielding microscale polyhedral biominerals. Co and Ni phosphates were precipitated at pH 7.5, following prior oxalate removal, resulting in near‐total Co recovery (>99%), while Ni phosphate yields were also high with a recovery maximum of 83.0%.
Highlights
In recent years, much attention has focussed on improving the security of supply and sustainability of critical metal resources through the development of cheaper and environmentally friendly systems for metal processing and extraction from low-grade ores, sludges and recycled materials (Watling, 2015; Werner et al, 2018)
We present a basis for selective biorecovery of Co and Ni oxalates and phosphates using reactive spent Aspergillus niger culture filtrate containing mycogenic oxalate and phosphate solubilized from struvite
Co recovery at pH 2.5 was high with a maximum of ~96% achieved, while ~60% Ni recovery was achieved, yielding microscale polyhedral biominerals
Summary
Much attention has focussed on improving the security of supply and sustainability of critical metal resources through the development of cheaper and environmentally friendly systems for metal processing and extraction from low-grade ores, sludges and recycled materials (Watling, 2015; Werner et al, 2018). Co is one such critical metal resource that faces steep projected increases in demand because of strategically important industrial applications in alloys, electrochemical materials and catalysts (Petavratzi et al, 2019). Since metal phosphates are soluble at low pH while simple divalent metal oxalates readily precipitate, we hypothesised that selective recovery of oxalates and phosphates could be achieved by manipulation of solution pH, thereby avoiding the simultaneous precipitation of oxalates and phosphates
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
