Israeli minerals technology company SelectREE has recorded in its latest laboratory results clear and repeatable element-specific electrochemical responses across its electrode systems, which marks meaningful progress in the company's proprietary effort to replace the conventional solvent extraction stage in rare earths separation with an electrochemical process.

The company's laboratory work covered four elements over dozens of runs conducted over several weeks, providing the first technical indication that SelectREE's approach to rare earth separation can consistently distinguish between individual elements.

"Consistently differentiating between elements is a foundational requirement for any selective separation process and provides the basis for the company’s next phase of development using real-world feed materials," SelectREE CEO Dr David Malka explains.

SelectREE's process is designed to be smaller, more modular and deployable closer to the source material, compared with conventional solvent extraction technologies.

Rare earths are typically found together and have very similar chemical properties, thereby making separation into individual, high-purity elements one of the most technically challenging stages of the supply chain. In fact, separation remains one of the most consequential bottlenecks in the critical minerals supply chain, says Cove Capital's Pini Althaus, who is a major investor in SelectREE.

The conventional method - solvent extraction - generally requires large chemical plants with hundreds of stages. These facilities can be capital-intensive, time-consuming to build and difficult to permit.

SelectREE's proprietary platform, in turn, is designed to change the separation stage and not the upstream leaching process. Ore or recycled material would still be leached using a solution selected for the relevant feedstock. The solution would then be processed through SelectREE's electrode-based system rather than through hundreds of solvent extraction stages.

The company's development plan consists of three principal stages, starting with demonstrating that its electrodes can distinguish between elements; validating the process using real feed materials; and deploying a pilot unit at a customer site.

In the longer term, SelectREE aims to enable mine operators, manufacturers and recyclers to separate metals closer to the point of production or recovery without waiting for a conventional centralised separation plant to be built.

The SelectREE platform is being developed for primary ore, end-of-life magnets, manufacturing swarf and other material streams.

The company also intends to evaluate applications of its technology beyond rare earths as a broader electrochemical tool for mineral separation and refining.