Selective extraction of rare earth elements from phosphoric acid by ion exchange resins

International audienceliterature review has been carried out to identify techniques allowing rare earth element recovery from phosphoric acid. These metals are present at low concentrations in solutions obtained after the attack of phosphate ores by sulfuric acid. The strongly acidic and complexing nature of this medium, as well as the presence of other traces metallic natural impurities (including iron and uranium), require the development of a particularly effective and robust process for the selective recovery of rare earth elements. Commercial solid supports are proposed to be tested, , the most promising seem to be those having functional groups as aminophosphonic acid (Tulsion CH-93, Purolite S940, Amberlite IRC-747, Lewatit TP-260), or as phosphoric acid (Lewatit VP OC 1026), or as phosphonic (Monophos, Diaion CRP200) or as diphosphonic, diphosphoric acid (Diphonix, Actinide-CU). A laboratory protocol test is described and carried out to explore the behavior of every main element with some of these resins in the phosphoric acid medium