Our research has uncovered that while REEs are prevalent in AMD, their concentrations are relatively low, posing significant extraction challenges. Utilizing advanced ion exchange technology provided by our partner, Cwenga, we've been able to refine the extraction process for these valuable elements.
Ion exchange technology involves using charged resin materials to capture and “swap” specific ions from a solution, enabling the targeted removal or recovery of desired substances. In our initial phase, many different resins were tested, and it was found that REEs could be extracted from the AMD effectively using cationic exchange resins. However, the high levels of iron (Fe) in AMD present a challenge, as Fe can interfere with the REE ion exchange process. To enhance REE recovery, we are pursuing strategies either to remove the iron or prevent it from binding to the resins.
During this project, our team also identified other Critical Raw Materials (CRMs) in AMD. This discovery broadened our focus, realizing that AMD could be a source not just for REEs but for any CRM (based on economic viability and geographical distribution). Interestingly, these CRMs can migrate from water to the surrounding soil, which has led us to investigate phytoremediation as a potential recovery strategy.