Renascor Resources Limited (ASX: RNU) has revealed that advanced mineral processing trials of the company’s eco-friendly purification process undertaken by leading German independent battery mineral consultancy group Dorfner ANZAPLAN have achieved results of 99.99% Carbon (versus anode industry standard of 99.95%.
Renascor Managing Director, David Christensen, said that over the past five years, the company’s technical team has developed an environmentally-friendly and cost-effective technology to purify Siviour graphite to meet the demanding requirements of lithium-ion battery anode manufacturers.
The results today demonstrate that, not only can we produce ultra-high purity graphite, but we can achieve these results whilst also delivering positive ESG outcomes,” Mr Christensen said.
“We expect these results to further support our plans for our 100% Australian-made Siviour Purified Spherical Graphite to become a world-leader in sustainable and ethically-sourced battery anode material for the lithium-ion battery market.”
Over the past five years, Renascor has undertaken comprehensive mineral processing tests on Siviour graphite and has adapted an HF-free caustic roasting technique to produce Siviour graphite concentrates to +99.95% C, the minimum purity level generally accepted for incorporation of natural flake graphite into lithium-ion battery anodes.
Caustic roasting involves using a caustic solution before roasting at low temperature and leaching. An important advantage of our caustic roasting process is that it offers an environmentally friendly process to purify graphite to battery-grade. In contrast, the purification technique generally used in China uses more environmentally harmful HF.
Since the completion of the Siviour Battery Anode Material Study in July 2020, Renascor has continued to develop and refine its HF-free purification technique through programs designed to optimise both the quality of the graphite produced through its use, as well as the projected cost at commercial scale4.
Recent tests have included purification trials undertaken by Dorfner ANZAPLAN, in collaboration with Renascor’s external engineering advisors Wave International.
Dorfner ANZAPLAN is a leading consultancy and engineering company with particular experience in battery minerals. Dorfner ANZAPLAN’s graphite expertise includes testing, developing, piloting and adapting mineral processing parameters to purify graphite concentrates to lithium-ion battery grade levels of +99.95% C. Wave International is an Australian-based resource development and engineering consultancy with extensive experience in the battery minerals sector, including acting in the capacity of external study manager and supervising engineers of Renascor’s Battery Anode Material Project5.
Renascor’s programme with Dorfner ANZAPLAN is designed to utilise Renascor’s historical work and parameters for producing PSG from Siviour graphite concentrates, validate its suitability for producing battery-grade anode material and optimise its application for use at commercial scale.
Initial production trials at ANZAPLAN successfully produced high-purity graphite from Siviour graphite concentrates, with results up to 99.98% C, in excess of the industry standard of 99.95% C6.
The most recent trials, which have included parameters designed to optimise reagent consumption, have achieved results of up to 99.99% C and have also confirmed that Renascor’s purification process can produce graphite that meets or exceeds lithium-ion battery anode purity specifications.
The trials are designed to include varying reagent regimes and to be performed on feedstocks of varying concentrate grade and type. This variation is considered critical to ensure that the processing parameters yield the production of qualifying PSG with all graphite concentrate feedstock expected to feed into the PSG processing plant. Results to date have achieved qualifying purity levels of each selected grade.
Mr Christensen said the results of the recent trials are significant because they provide further validation of Renascor’s eco- friendly purification technique and its suitability to achieve ultra-high, battery-grade purity.
The results are also significant because they further support Renascor’s leading environmental and social credentials, including the ability to achieve ultra-high purity, while using an eco-friendly, HF- free purification process.
Finally, the results offer further support for the efficiency of Renascor’s purification technology and support Renascor’s plans to optimise reagent consumption and produce PSG at globally competitive costs.
The purification trials with Dorfner ANZAPLAN are scheduled to conclude in June 2021, with results to be used for detailed engineering design for construction of Renascor planned PSG manufacturing facility in South Australia.