Method of recovery of scandium
AssigneeNippon Steel Corporation
InventorsJunichi HIRATA, Kyohei ISHIKAWA, Michihiro AIMOTO, Yusuke SHIMADA, Manabu HOSHINO
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Abstract
A method of recovery of scandium, in recovery of scandium in iron and steel slag, for recovering scandium from the iron and steel slag while also roughly separating the scandium and other rare earth elements, comprising leaching out rare earth elements including scandium from the iron and steel slag several times in different ranges of pH and, furthermore, combining the leaching solution acquired using this method with a step for separating elements to recover the scandium with a high efficiency.
Claims18
A method of recovery of scandium (Sc) from iron and steel slag produced by an ironmaking process, the method of recovery of scandium comprises:
- adjusting a pH of a leaching solution obtained by bringing a first acid into contact with the iron and steel slag to within a first pH range to obtain a first leaching solution,
- separating solids from the first leaching solution, and
- adjusting a pH of a leaching solution obtained by bringing a second acid into contact with the solids separated by the separating to become within a second pH range lower than the adjusting the pH of the leaching solution obtained by bringing the first acid into contact with the iron and steel slag to obtain a second leaching solution, and
- where the first acid and the second acid include nitric acid or sulfuric acid, the first pH range is 1.1 or more and less than 6.7, and the second pH range is −1.0 or more to the first pH range.
Dependencies are inferred from the claim text.