Method of processing nuclear fuel scraps

摘要

High-purity uranium can be effectively recovered from gadolinium-containing nuclear fuel scraps by dissolving the scraps in a mineral acid, extracting uranium from the resulting solution with a solvent, washing the organic phase with water or a dilute mineral acid, and counter-extraction with water or a dilute mineral acid. This invention also provides an efficient method of recovering high-purity gadolinium from the acidic washings coming from the above washing step and containing small amounts of radioactive elements (uranium, thorium and others) by adding an alkali, removing the precipitate thus formed, lowering the pH of filtrate to 2 or less, and adding an oxalic acid source to precipitate gadolinium oxalate.