A procedure for the efficient extraction and separation of rare earths and other valuable elements from used NdFeB permanent magnets is presented. In a first step, an iron free leachate is prepared from an used magnet using nitric acid. Cobalt is separated through a liquid–liquid extraction in aqueous nitrate media using as organic phase the ionic liquid trihexyl(tetradecyl)phosphonium nitrate ...

X-ray absorption and magnetization experiments are used to describe the oxidation states of the rare earth ions R=Ce, PI and Tb in the double layer high-Tc superconducting series RBa2Cu307 and Pb2Sr2R1-,CaXCu3O8. We obtained the same oxidation states for the rare earths in these two classes of compounds, namely, R=Ce tetravalent and R=Pr and Tb trivalent.

Three fungal strains were found to be capable of bioleaching rare earth elements from monazite, a rare earth phosphate mineral, utilizing the monazite as a phosphate source and releasing rare earth cations into solution. These organisms include one known phosphate solubilizing fungus, Aspergillus niger ATCC 1015, as well as two newly isolated fungi: an Aspergillus terreus strain ML3-1 and a Pae...