A comparison of two methods of recovering cobalt from a deep eutectic solvent: Implications for battery recycling

Solvometallurgical recovery of cobalt from lithium-ion battery cathode materials using deep-eutectic solvents

“…Choline chloride is an inexpensive chicken feed additive, produced at a large scale. 40,44,45 Citric acid is a renewable, non-toxic and relatively cheap organic acid, produced at large scale as well. 46,47 The choline chloride-citric acid DES is used as a lixiviant and more polar phase in non-aqueous solvent extraction (nonaqueous SX).…”

Metal extraction from a deep eutectic solvent, an insight into activities

“…The estimated standard deviation was 8.1% and the amount of radioactivity recovered from the shaking vials on average within 2.7% of the amount added to the vial. *** The distribution ratio for technetium for 10% aliquat 336 in ethyl benzene when the lower phase was the DES was 2.75 (6). The estimated standard deviation was 2.3% and the amount of radioactivity recovered from the shaking vials on average within 2.6% of the amount added to the vial.…”

“…Using a 30% solution of tetra-(2-ethylhexyl) malonamide in a nontoxic diluent (solvent 70) 43 a series of solvent extraction experiments were conducted at 30 1C using a dilute solution of gold(III) chloride in mixtures of sodium and choline chlorides (total chloride concentration maintained at 3.87 M). Solvent extraction experiments were also performed using solutions of gold chloride in mixtures of ethaline and either aqueous sodium chloride or aqueous choline chloride.…”

“…As the Debye-Hückel term in the SIT equation depends only on the medium and the ionic strength (I, I = [Na + ] + [Ch + ]) § § which was kept constant in our experiments we can simplify our equations greatly. We can write eqn (6).…”

Review on Hydrometallurgical Recovery of Metals with Deep Eutectic Solvents

“…Another possible issue comes from the formation of complexes in the DES. Albler et al ( [58]) found that the formation of cobalt-lactate complexes in the DES inhibits the extraction of cobalt by tri-alkylamines extractants. The DES used for the leaching has to be selected properly to avoid this kind of issue.…”