Separation of rare earths and other valuable metals from deep-eutectic solvents: a new alternative for the recycling of used NdFeB magnets

Abstract

Neodymium and dysprosium can be separated using a new extraction system based on a deep-eutectic solvent and Cyanex® 923 diluted in toluene.

Synthesis and Dissolution of Metal Oxides in Ionic Liquids and Deep Eutectic Solvents

“…A significantly better performance was found for choline chloride-lactic acid (molar ratio 1:2), attributed to the presence of acidic protons. Furthermore, the coordinating abilities of lactate or choline are assumed to have a positive effect [152].…”

Phenolic hydrogen bond donors in the formation of non-ionic deep eutectic solvents: the quest for type V DES

“…4 In the last decade, a large amount of research on DES has been carried, from fundamental studies to applications. [4][5][6][7][8][9] The binary nature of DES allows for the formulation of a tailored solvent for a given application through judicious selection of its constituents. However, most DES are based on at least one ionic species and dominated by strong hydrogen bonding interactions, rendering the resulting mixture hydrophilic.…”

Green solvents in urban mining

“…The Binnemans group performed several very interesting works on the recycling of real NdFeB magnets [38][39][40], mainly differing by the leaching step: mineral acid [38], ILs [40] or DES [39]. This impacts the consecutive extraction steps: thiocyanate ionic liquid and phosphorylated extractant in toluene [39], chloride-based IL [38] or change in temperature to induce the biphasic state [40]. Finally, precipitation is always performed with oxalic acid.…”

“…Finally, precipitation is always performed with oxalic acid. The great care dedicated to the recycling of all chemicals [40] and the scability [39] should be commended.…”