Status and advances of deep eutectic solvents for metal separation and recovery

Abstract

The increasing discharge of metal-associated waste not only causes growing concerns on the environment and human health but also accelerates the depletion of natural metal resources. Within this context and...

Choline chloride–ethylene glycol based deep-eutectic solvents as lixiviants for cobalt recovery from lithium-ion battery cathode materials: are these solvents really green in high-temperature processes?

“…The leaching of cobalt is achieved by the reduction of cobalt( iii ) in LCO or NMC to the more soluble cobalt( ii ). 19 Recently, we investigated the use of a choline chloride–citric acid based DES as lixiviant for the leaching of LCO. Quantitative cobalt leaching was achieved after one hour at 40 °C using metallic copper (already present as LIB-current collector) as reducing agent for cobalt( iii ).…”

Fortification of thermal and structural stability of hemoglobin using choline chloride-based deep eutectic solvents

“…[26][27][28] Other than having a low melting point and convenient preparation, DESs have gained superiority due to their high atom economy, biodegradability, and their ability to be easily re-used and recycled. 29 Among many different HBAs, [Ch]Cl is the most commonly used HBA because of its biocompatibility and biodegradability. 30 Moreover, tonnes of [Ch]Cl are produced annually to be used as an animal feed supplement, and therefore, it is not expensive.…”

Solution Thermodynamic Properties of {Tetrabutyl Ammonium Bromide:Glycerol} Hydrophilic DESs at T = 298.15–348.15 K and 0.1 MPa and an Approach over Solvent Extraction of Cr(VI) Using {Tetrabutyl Ammonium Bromide:Decanoic Acid/Oleic Acid} Hydrophobic DESs

“…However, solvent extraction techniques have several advantages over other procedures, including the ability to conduct the removal in atmospheric conditions, the use of relatively basic equipment, being highly economical, having a simple reactor design, depicting ease in scale-up processes, and requiring only modest volumes of extractant . Besides ionic liquids (ILs), solvent extraction using deep eutectic solvents (DESs) is preferred as an alternative, as they are eco-friendly and have an economical approach for efficiently removing heavy metals from polluted water streams . Paul Walden initially discussed 19 ionic liquids in 1914, and no one could have predicted that they would become a major scientific area with widespread technology growth.…”

“…18 Besides ionic liquids (ILs), solvent extraction using deep eutectic solvents (DESs) is preferred as an alternative, as they are eco-friendly and have an economical approach for efficiently removing heavy metals from polluted water streams. 19 Paul Walden initially discussed 19 ionic liquids in 1914, and no one could have predicted that they would become a major scientific area with widespread technology growth. The utilization of ILs varied based on the choices of several types of cations and anions, preparation methods, the molar ratio of binary liquids, the freezing point of the mixture, and others.…”