QEM Limited (ASX: QEM) has partnered with The University of Queensland to produce the first high purity vanadium pentoxide (V2O5) from an industrial waste stream in Australia. V2O5 is the essential component of the electrolyte used in vanadium flow batteries.
QEM supplied UQ with the spent catalyst to be used in the project. On 27 June 2023, QEM announced it had entered into an agreement with Incitec Pivot to collect the vanadium-bearing spent catalyst from IPL’s Mount Isa Sulphuric Acid Plant and process this waste into high purity vanadium pentoxide (V2O5).
QEM also entered into a similar agreement in March 2023 for the supply of spent catalyst from Sun Metals’ Townsville Zinc Refinery.
These collaborations with Sun Metals and IPL represent Circular Economy opportunities where industrial waste can be repurposed to a higher use by extracting the critical mineral vanadium as V2O5. V2O5 is the essential component of the electrolyte used in vanadium flow batteries (VFB), critical to achieving Australia’s carbon reduction targets.
Currently the spent catalyst removed from sulphuric acid plants ends up in waste facilities. This project aims to provide a circular economy solution to this industrial waste stream by extracting the vanadium and putting it back into the economy as a high value product.
Test work previously conducted by QEM and Clean-Teq Water, established that 90% of the battery grade vanadium present can be extracted using known techniques. The collaboration with UQ is a further step in demonstrating Vanadium recovery.
The first stage of the collaboration between QEM and UQ involved a small-scale laboratory demonstration of all the processing steps in recycling the spent catalyst into a high purity vanadium oxide product.
This research and development project is led by UQ Associate Professor James Vaughan and is part of the Resources Technology and Critical Minerals Trailblazer which aims to advance critical mineral processing technology readiness.
“This project is an exciting demonstration of the circular economy of vanadium, the key ingredient in vanadium flow batteries which can provide large-scale and long-duration energy storage, complementing renewable electricity generation,” Associate Professor Vaughan said.
QEM Managing Director Gavin Loyden said the waste recycling project with UQ ties strongly to the company’s ESG goals to position its projects and activities at the forefront of environmental and social responsibility within the mining and energy sectors.
“This collaboration with UQ builds on QEM’s umbrella agreement with the university from September 2022 when The University of Queensland’s Sustainable Minerals Institute commenced mineral characterisation and beneficiation work for QEM’s flagship critical minerals project by characterising the mineralogy of QEM’s Julia Creek shale post-oil extraction to assist in optimising vanadium beneficiation to further improve vanadium pentoxide yields,” he said.
“With UQ’s assistance, QEM seeks to accelerate the introduction of Queensland-sourced and processed V2O5 into the market. QEM remains committed to its goal of supplying V2O5 from our primary vanadium resource at Julia Creek,” said Mr Loyden.
The work undertaken by UQ included laboratory test work to determine the required process conditions for an acid leach/solvent extraction flowsheet for the spent catalyst. The program also included assaying the V2O5 that was produced in the study to determine purity of the product.
Acid leaching tests were conducted with various solid loading concentrations, acid concentrations and different feed grind sizes. After filtration of the slurry, oxidation of the leachate and partial neutralisation were performed; then, solvent extraction was utilised to reject impurities and provide a more concentrated feed for ammonium metavanadate (AMV) crystallisation. Finally, calcining of the AMV was performed to obtain V2O5.
The V2O5 sample obtained was then assayed by digestion and Inductively Coupled Plasma Optical Emission Spectroscopy; the largest impurity identified in the V2O5 sample had a value limit of 0.06% while four impurity elements reported a value of 0.02% each.
Twenty-four potential impurity elements reported below detection limits. The results represent a V2O5 purity of >99%, which was the goal of the study.
UQ is optimising processing conditions for subsequent piloting, as well as producing larger samples of V2O5 for potential future marketing purposes.