Patent ID: 9663842
Date: 2017-05-30
CPC Classifications: C22B

Claim:
1. A method for recovering a rare earth element from ore including a first group of metals selected from a group consisting of at least one of iron and aluminum, and a second group of metals selected from a group consisting of at least one of the following rare earth elements: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, yttrium and scandium, the method comprising: drying the ore at a temperature from 20° C. to 150° C.; contacting the ore with a sub-stoichiometric amount of sulfuric acid to obtain a mixture of ore and sulfates of the first group of metals; subjecting the mixture to a temperature between 620° C. and 750° C. to convert the sulfates of the first group of metals into a stable species and the second group of metals into sulfates, thereby obtaining a mixture of impurities and rare earth sulfates; adding water to the mixture of impurities and rare earth sulfates, selectively dissolving the rare earth sulfates and forming a rare earth solution; and subjecting the rare earth solution to a purification process.