JOHANNESBURG (miningweekly.com) – Flotation tests conducted by Perth-based Independent Metallurgical Operations at Strike Resources’ high-grade Burke graphite project, in Queensland, have confirmed that a concentrate of purity in excess of 95% and up to 99% total graphitic carbon (TGC) can be produced using a standard flotation process.
ASX-listed Strike is now preparing further samples of high-purity graphite concentrate, to be used to determine its suitability for use in lithium-ion batteries. The application of graphite as an anode material for these batteries currently dominates the battery industry.
There is typically more graphite by weight than lithium in a lithium-ion battery and with the use of lithium-ion batteries expected to substantially increase over the coming years, the company believes that there will be great demand for its graphite.
Strike says that the testing will include the preparation of battery electrodes from samples of its graphite and the construction of coin battery cells using these electrodes.
The cells will be repeatedly cycled with electrical charge/discharge and the performance independently assessed and compared with batteries made with baseline natural graphite material.
It is expected that the results of this work will be available by May or June.
Meanwhile, the miner is in ongoing discussions with major Chinese lithium-ion battery manufacturers and graphite companies, which have expressed keen interest in its products. It is also in discussions with Australian universities and research institutions to research the development of commercial applications for its graphite.
GRAPHENE EXFOLIATION
Meanwhile, Strike says it is continuing to optimise the production of graphene from its graphite, using a process known as electrochemical exfoliation (ECE).
Noting that graphene is a recently discovered “wonder material” that offers tremendous opportunities in a range of industries, possessing exceptional qualities of strength, electrical and thermal conductivity and impermeability, it had successfully extracted graphene nano platelets (GNP) directly from natural unprocessed drill-core taken from the Burke project, using the ECE process.
Graphene is technically defined as a single atom layer of crystalline carbon in a two dimensional ‘honeycomb’ type structure, but the term graphene is often extended to include material made up of multiple stacked single layers.
The ECE process is relatively low cost and environment-friendly compared with other processes, yet it can produce high purity graphene products. The ECE process, however, is not applicable to the vast majority of worldwide graphite deposits as it requires a TGC of more than 20%.
“Initial test results are very promising with the current testing evaluating a range of different chemical solutions, anode configurations and graphene harvesting techniques, to improve recovery rates and graphene purity,” the company notes.