目前,加拿大安大略省埃利奥特湖铀矿山有大量含稀土、钍的贫铀溶液被废弃,这是铀矿石的硫酸浸出液经清液离子交换法回收铀后的贫液。现在那里只有一个矿山用烷基磷酸的溶剂萃取法从离子交换法回收铀后的贫液中回收稀土浓缩物。但为了回收稀土,须先分离钍和铀。目前所采用的是 At present, a large amount of depleted uranium solution containing rare earth and thorium is discarded at the Elliott Lake uranium mine in Ontario, Canada, which is a lean solution after uranium is recovered from the uranium ore sulfuric acid leachate by the supernatant ion exchange method. There is now only one mine where rare earth concentrates are recovered from spent leachate recovered by ion exchange using solvent extraction of alkylphosphoric acid. However, in order to recover rare earths, thorium and uranium must be separated first. Currently used is