King River Resources Ltd (ASX:KRR), which hopes to become a world-leading producer of 4N (99.99% purity) high purity alumina (HPA), has produced a 5N (≥99.999%) purity precursor compound.
The precursor production is an important step for the company towards the definitive feasibility study for its High Purity Alumina Project and proposed Kwinana plant near Perth.
King River tapped analytical service provider Source Certain International (SCI) to produce several batches of the high purity 5N precursor.
5N precursor details
The precursor was produced through King River’s ARC HPA process from an industrial aluminium chemical compound feedstock; highlighting the Aluminium feedstock, the use of only Recrystallisation steps in purification and final Calcination.
SCI assayed the precursor using inductively coupled plasma-mass spectrometry (ICP-MS) and ICP-atomic emission spectroscopy (ICP-AES) methods, completing up to 5 duplicate analyses on each batch to improve confidence in the results.
The 5N purity result was calculated by the addition of all the assayed element impurities that reported above the detection limit then subtracting this result from 100%.
The main contaminants in the precursor were potassium (K), silicon (Si) and sodium (Na), with other elements less than 1 part per million (ppm) or below the detection limits.
Repeat assays for Precursor Batches 8-13.
Next steps
A pre-feasibility study (PFS) released in June confirmed the value of the proposed Kwinana HPA plant’s technical and economical viability, and affirmed King River’s decision to initially focus on entering the global HPA market.
The PFS forecast a production rate of 9,000 tonnes per annum of 99.99% high purity alumina (HPA) once at full production, with project revenue of more than $7 billion over 25 years.
HPA is an essential ingredient in the production of LEDs and lithium-ion battery separators, both of which are used in clean energy and high technology applications, such as lighting and electric vehicles (EV) - as such, demand for HPA is expected to increase.
Metallurgical test-work is ongoing to further refine the ARC HPA process for the DFS with the current focus on further improving the precursor product to simplify the final calcination stage.
King River has also begun the development of a mini pilot plant to demonstrate the ARC HPA process works at a larger scale for the DFS and to produce market samples.
The process flowsheet and mass balances have been used to scale the mini pilot plant and enquiries and purchase orders with vessel vendors are underway.
- Daniel Paproth