|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Rare Metal Extraction & Processing
||Uranium and Thorium Removal from Rare Earth Sulfate Solutions by Ion Exchange and Solvent Extraction
||David Dreisinger, Mike Johnson, Niels Verbaan, Greg Andrews
|On-Site Speaker (Planned)
The Search Minerals Direct Extraction Process involves direct acid treatment of crushed ore, water leaching and neutralization for iron and impurity removal and mixed carbonate precipitation. The rare earth carbonate is redissolved in sulfuric acid and treated by pH adjustment to remove silica and aluminum followed by ion exchange for uranium removal and solvent extraction for thorium removal. The treated solution is then sulfidized to remove zinc and subsequently processed to make either a mixed oxide rare earth or a mixed carbonate rare earth product for separation into high purity individual rare earths. The bench and pilot plant processing of rare earth sulfate solutions derived from the Foxtrot Deposit for uranium and thorium removal is described.