Recovering critical minerals with 'super fungi'

A ‘superpowered’ fungus engineered at UQ’s Biosustainability Hub could be used to extract critical minerals from toxic mining waste while also helping to remediate sites.

AIBN’s Dr Denys Villa-Gomez and Fernanda Soto-Montandon are growing unique fungal strains that can be used to detoxify mining tailings and capture traces of important rare earth elements without the need for harsh chemicals.

Alternative to harsh chemicals

Critical minerals are currently recovered from mining tailings using a method called leaching, which relies on acids and solvents that are expensive and can be damaging to the environment. 

A new leaching method pioneered by Dr Villa-Gomez instead uses ‘super fungi’ strains that produce organic acids capable of cleaning mine waste and recovering valuable metals.

“We take fungi that grows naturally in mining areas and then we engineer them so they can cope with toxic environments and tolerate harsh conditions,” Dr Villa-Gomez said.

“We know the process works well for extracting high-value critical minerals such as vanadium and scandium which are integral for making grid-scale batteries, strengthening steel and producing light weight alloys.”

Remediating mine sites

Dr Villa-Gomez said exploring the use of fungus as a bioleaching tool was an environmentally responsible and cost-effective alternative to traditional mineral extraction processes.

“In the future, it’s hoped we could deploy these fungi directly at mine sites, recovering minerals while helping remediate the land at the same time,” she said.

“We are engaging with industry partners to test these technologies in the field.”

Evolution of super strains

The creation of the ‘super fungi’ is done through adaptive laboratory evolution, where the fungi are put under challenging conditions over time so that only the strongest survive and evolve into more effective strains.

“It’s like a superhero gaining powers,” Dr Villa-Gomez said.

The researchers then process the mining waste by combining it with the engineered fungi (and their feedstock) in state-of-the-art bioreactors at UQ’s Biosustainability Hub.

Metabolism provides value 

Ms Soto-Montandon said as the fungi consumes the feedstock they begin producing natural organic acids as part of their metabolism.

“Those acids then break down the mining waste, destabilising the mineral structure and releasing the trapped metals into a liquid form,” she said.

“From there, the metals can be recovered and reused, turning what was once waste into a valuable resource through a low impact biological process.”

Dr Villa-Gomez is also a Senior Lecturer at UQ’s School of Civil Engineering.

UQ's Biosustainability Hub uses synthetic biology to help the world’s biggest businesses transition to net zero.
Funded by government, industry and UQ, the $70 million Biosustainability Hub is a one-stop-shop for big companies to transform their production practices and create carbon neutral economically viable products and materials.