SYSTEM AND METHOD OF EXTRACTION OF RARE EARTH ELEMENTS

文件类型：PDF文档
文件大小：1456K
FIELD : chemistry. SUBSTANCE : invention relates to a process of recovering rare earth elements from low grade ores, comprising a first metal selected from the group consisting of at least one metal selected from iron and aluminium and a second metal selected from the group consisting of at least one of rare earth elements, such as lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, yttrium and scandium. The method comprises the steps of : (i) contacting the ore with sulfuric acid to produce sulfates of metals of the first group, (ii) exposure to high temperatures to convert the first sulphate groups phosphates or other stable substance, and the second group - a sulphate, (iii) adding water to cooling the mixture and selective dissolution of the rare earth elements, and (iv) cleaning solution. EFFECT : reduction of impurities in the recovered product. 12 cl, 9 dwg, 5 tbl, 4 ex