Recycling of rare earths from NdFeB magnets using a combined leaching/extraction system based on the acidity and thermomorphism of the ionic liquid [Hbet][Tf₂N]

Abstract

A new recycling process was developed to recover rare earths from roasted NdFeB magnets using the thermomorphic and acidic properties of the ionic liquid [Hbet][Tf2N] to achieve a combined leaching/extraction system.

Selective leaching of rare earth elements from bauxite residue (red mud), using a functionalized hydrophobic ionic liquid

“…HbetTf2N and Sc, Fe ions than the other REE and base metal ions. This affinity has been confirmed also in other studies (Dupont and Binnemans, 2015b;Hoogerstraete et al, 2013;Onghena and Binnemans, 2015) and can be utilized in the process for generating a Sc enriched stream after consecutive stripping steps. Decreasing volume ratio of the stripping solution/IL can provide a more concentrated REE stream, overcoming issues associated with high acid consumption and generation of large aqueous waste streams.…”

“…Metals dissolved into HbetTf2N are extracted in a subsequent stripping step with an acidic solution at ambient temperature regenerating the IL which due to hydrophobicity is separated from the aqueous solution for reuse. This leaching strategy has been studied for phosphor lamps waste powder and neodymium magnets where selective dissolution of the REE against other metals was successfully proven (Dupont and Binnemans, 2015a;Dupont and Binnemans, 2015b).…”

Dissolution of the Rare‐Earth Mineral Bastnaesite by Acidic Amide Ionic Liquid for Recovery of Critical Materials

“…Ionic liquids have also been extensively used to dissolve metal oxides, minerals, and other compounds. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] The BASIL TM (Biphasic Acid Scavenging utilizing Ionic Liquids) process, developed by BASF, displays the green chemistry opportunities of ionic liquid applications by producing photoinitiator precursor alkoxyphenylphosphines and allowing the recycling of the IL post-process. [30] In this work, the acidic amide IL N,N-dimethylacetamidium bis-(trifluoromethylsulfonyl)imide (DMAH + NTf 2 -) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIM + NTF 2 -) diluent was used to dissolve froth flotation concentrate bastnaesite and synthetic bastnaesite analogues [RE(CO 3 )F].…”

Unusual seeding mechanism for enhanced performance in solid-phase magnetic extraction of Rare Earth Elements

“…Solvent extraction is industrially the most extensively used separation technique at present141516171819 and although it is possible to accomplish rather high extraction and separation factors, it is associated with considerable challenges such as the need in big volumes of extractant in high concentrations, which translates into elevated costs and environmental hazards. Ionic liquids (IL) have been also intensively investigated20212223 and appeared as a promising and environmentally friendlier alternative to compared to conventional solvent extraction. However, they usually require operation at elevated temperatures (which results in high costs), and some of them, for instance fluorinated IL, being harmful compounds both for human health and environment.…”