How Impact Minerals Plans to Revolutionise WA’s Potash and Acid Supply

A New Development Pathway Emerges

Impact Minerals Limited (ASX – IPT) has announced a significant advancement in its Western Australian portfolio with the identification of a standalone development pathway to produce sulphate of potash (SOP) and hydrochloric acid (HCl) from lake clays. This initiative operates independently from, yet complements, the company’s existing Lake Hope High Purity Alumina (HPA) project.

The breakthrough comes from metallurgical test work demonstrating exceptionally high recoveries of sulphate, exceeding 94%, and chlorine extraction rates above 98%. These results suggest the potential to produce SOP fertiliser and hydrochloric acid efficiently, sidestepping the evaporation pond methods that have historically hindered Australian SOP projects.

Strategic Location and Market Opportunity

Impact Minerals has secured several lake tenements near Salmon Gums, strategically positioned to serve Western Australia’s Wheatbelt farming regions with potash and the Eastern Goldfields mining sector with hydrochloric acid. The Salmon Gums project, held within an 80 – 20 joint venture with Playa One Limited, leverages proximity to these markets, potentially reducing logistics costs and improving supply reliability.

Australia currently imports all of its SOP requirements, a premium fertiliser valued for its high sulphur content and low chloride levels, essential for chloride-sensitive crops. Meanwhile, hydrochloric acid remains in high demand across the Goldfields for gold processing and emerging rare earth element projects, with local supply constrained.

Innovative Salt Calcination Process

The process under investigation involves salt calcination, where lake clays are mixed with chloride salts and heated. This releases potassium and sulphate into solution for SOP recovery and chlorine gas that can be captured as hydrochloric acid. Notably, this method produces an aluminium-rich residue, potentially adding further value.

Unlike traditional SOP production reliant on evaporation ponds vulnerable to weather and operational challenges, this calcination approach is climate-independent and yields a potassium–sulphate dominant solution, simplifying crystallisation and potentially enabling a more compact plant design.

Next Steps and Market Engagement

Impact Minerals is advancing the opportunity with ongoing metallurgical optimisation, refinement of SOP crystallisation, and further chlorine capture testing. A Scoping Study is underway to evaluate capital and operating costs, product specifications, and development scale. Results from this next phase are expected in the second quarter of 2026.

Managing Director Dr Mike Jones emphasised the potential to fill a noticeable supply gap for both fertiliser and industrial acid in Western Australia, highlighting the strategic advantage of the Salmon Gums location and the complementary nature of this project alongside the Lake Hope HPA development.

Engagement with fertiliser, chemical, and industrial partners is planned to explore market development and potential collaborations, signalling a proactive approach to commercialisation.