METHOD OF DETERMINING IMPURITIES IN SCANDIUM OXIDE Russian patent published in 1997 - IPC

FIELD: analytical methods. SUBSTANCE: invention deals with method in which scandium oxide sample is treated with mineral acid solution at heating, solid part is separated, and aqueous solution containing impurities is analyzed by atomic emission method. According to invention, sample is treated by 45-50% hydrofluoric acid with initial sample to acid solution ratio 1: (34-68) and treated material is then heated until dry residue containing scandium fluoride with impurities is obtained. Subsequent separation of main element is accomplished by treating dry residue with dilute (from 1:40 to 1: 50) hydrochloric acid solution under 10-15-min heating to produce solution containing impurity elements and insoluble scandium fluoride residue. Solution-residue mixture is supplemented with polyacrylamide solution with concentration 2-3 g/l and solids/liquid ratio is adjusted to 1:(2-13) by adding hot dilute HCl solution. Mixture is allowed to stand for some time and clarified part of solution is decanted to be analyzed for impurity elements by atomic emission technique. EFFECT: increased reliability of analysis. 3 cl, 1 tbl