Protic ionic liquid‐based deep eutectic solvents with multiple hydrogen bonding sites for efficient absorption of NH₃

Abstract

The emerging of ionic liquids (ILs) provides an efficient and sustainable way to separate and recover NH 3 due to their unique properties. However, the solid or highly viscous ILs are not suitable for traditional scrubbing. Therefore, an effective strategy was proposed by combining the protic ILs (PILs) with acidic H and low viscous ethylene glycol (EG) to form IL-based deep eutectic solvents (DESs) for NH 3 absorption. The results indicated that these PIL-based DESs not only have fast absorption rate, but also exhibit exceptional NH 3 capacity and excellent recyclability.The highest mass capacity of 211 mg NH 3 /g DES was achieved by [Im][NO 3 ]/EG with molar ratio of 1:3, and was higher than all the reported ILs and IL-based DESs, which was originated from multiple hydrogen bonding between acidic H and hydroxyl groups of the DESs and NH 3 . This work will provide useful idea for designing IL-based solvents for NH 3 separation applications.

Remarkable NH3 absorption in metal‐based deep eutectic solvents by multiple coordination and hydrogen‐bond interaction

“…Therefore, the effect of water on NH 3 solubilities in metal‐based DESs prepared in this work is very minor. Table 2 presents the comparison of NH 3 solubilities in different DESs and ILs 25,36–50,65–76 . It is found that the solubilities of NH 3 in metal‐based DESs prepared in this work are remarkably high, especially at low pressures.…”

“…Therefore, DESs have the potential to replace ILs for highly efficient and reversible gas absorption. [31][32][33][34][35] As for the application of DESs in reversible NH 3 absorption, there have been some impressive examples such as ChCl + PhOH + EG DESs, 36 NH 4 SCN + Gly DESs, 37 EaCl + Gly DESs, 38 ChCl + TetrZ + EG DESs, 39 MAA + TetrZ DESs, 40 [Im][NO 3 ] + EG DESs, 41 [emim]Cl + BenTriz DESs, 42 [ImH] Cl + Gly DESs, 43 LiCl/EG DESs, 44 and [MeC OH 3 N]Cl/U. 45 After careful examination on these DESs, it can be found that they are typically constituted by one weak acidic compound (e.g., PhOH, NH 4 46 EaCl + Res DESs, 47 and [TMPDA]Cl 2 + PhOH DESs 48 ).…”

“…25,[36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][65][66][67][68][69][70][71][72][73][74][75][76] It is found that the solu-…”

Utilization of Deep Eutectic Solvents to Reduce the Release of Hazardous Gases to the Atmosphere: A Critical Review

“…The extraction efficiency of sulfur compounds depends on the alkyl-chain length of the HBA; for example, the DES with longer alkyl chain length on the HBA had a higher thiophene distribution capacity. Warrag et al [ 128 ] found very high selectivity (higher than that of ILs and DESs) for thiophene using TEAC/gly (1:2) DES but the distribution capacity was lower using the same glycerol but DESs. When glycerol was replaced with EG in the DES, higher distribution coefficient was achieved compared to glycerol-based DES owing to the higher thiophene solubility in the EG-based DES.…”

Performance and mechanism of the separation of C8 α‐olefin from F‐T synthesis products using novel Ag‐DES

“…Compared with the traditional solvent ILs, most of DESs exhibit a lot of remarkable advantages such as desirable biodegradability, environmental friendliness, ease of preparation for large‐scale applications, and show great interests in many fields 17,19 . DESs have been widely used in the extraction separations, 19 natural products extraction, 20 gaseous mixture separations, 21,22 catalysis, 23,24 dissolution and modification processes, 25 electrochemistry, 26 and material chemistry 27 . Jiang et al 28,29 have achieved a favorable separation performance in ethylene/ethane by a novel supported liquid membrane with DESs as the carrier.…”