Revisiting the Physicochemical Properties and Applications of Deep Eutectic Solvents

Recently, deep eutectic solvent (DES) or ionic liquid (IL) analogues have been considered as the newest green solvent, demonstrating the potential to replace harsh volatile organic solvents. DESs are mainly a combination of two compounds: hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD), which have the ability to interact through extensive hydrogen bonds. A thorough understanding of their physicochemical properties is essential, given their successful applications on an industrial scale. The appropriate blend of HBA to HBD can easily fine-tune DES properties for desired applications. In this context, we have reviewed the basic information related to DESs, the two most studied physicochemical properties (density and viscosity), and their performance as a solvent in (i) drug delivery and (ii) extraction of biomolecules. A broader approach of various factors affecting their performance has been considered, giving a detailed picture of the current status of DESs in research and development

Partitioning behavior of dyes in ionic liquids induced aqueous biphasic systems of PPG 725 & ammonium salts

Polypropylene glycol (PPG) is one of the most utilized polymers in aqueous biphasic systems. The low polarity of the polymer-rich phase restricts the application of the ABSs. The applicability of polymer rich ABSs can be induced by adding little amount of ionic liquids as adjuvants. Therefore, an analysis involving the introduction of a small amount of imidazolium-based ILs to PPG 725 + ammonium salts ABSs was performed. The phase diagrams as well as the partitioning behavior of dyes: Orange II (OII), Eriochrome Black T (EBT) and Brilliant Green (BG) were investigated. The addition of 5% 1-butyl-3-methylimidazolium acetate, [BMIM][AC] modulates the partition behaviors of all the investigated dyes. The employed ILs and dyes partitioned preferentially into the polymer-rich phase. The partition coefficients (Kdye) for all the dyes follow the sequence: BG > EBT > OII in all investigated ABSs. The results obtained are in accordance with the logarithm of octanol-water partition coefficients (log Kow) of the respective dyes. The recovery of BG dye from polymer phase has been studied successfully by adsorption onto chitosan.</p

Revisiting the Physicochemical Properties and Applications of Deep Eutectic Solvents

Recently, deep eutectic solvent (DES) or ionic liquid (IL) analogues have been considered as the newest green solvent, demonstrating the potential to replace harsh volatile organic solvents. DESs are mainly a combination of two compounds: hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD), which have the ability to interact through extensive hydrogen bonds. A thorough understanding of their physicochemical properties is essential, given their successful applications on an industrial scale. The appropriate blend of HBA to HBD can easily fine-tune DES properties for desired applications. In this context, we have reviewed the basic information related to DESs, the two most studied physicochemical properties (density and viscosity), and their performance as a solvent in (i) drug delivery and (ii) extraction of biomolecules. A broader approach of various factors affecting their performance has been considered, giving a detailed picture of the current status of DESs in research and development

Estimation of speed of sound in binary mixtures of cyclohexane with benzene, benzaldehyde or cyclohexylamine, and, cyclohexylamine with benzene in the temperature range (293.15–323.15) K employing empirical and theoretical models

492-497Speed of sound in the binary mixtures of cyclohexane with benzene, benzaldehyde or cyclohexylamine, and, that of cyclohexylamine with benzene over the entire composition range and at (293.15, 303.15, 313.15 and 323.15) K has been estimated employing several models, viz., Nomoto model (NM), Van Dael model (VM), Junjie model (JM), Ernst et al. model (EM), Impedance model (IM), Collision factor theory (CFT), Intermolecular free length theory (FLT), and, Prigogine-Flory-Patterson theory (PFPT). <span style="font-size:9.0pt; mso-bidi-font-size:11.0pt" lang="EN-US">The maximum deviations between estimated and experimental speed of sound by different models NM, VDM, JM, EM, IM, CFT, FLT, and PFPT are –24.5, –23.0, 20.2, –48.3, –22.1, –24.9, 25.0, and 24.4 m s-1, respectively. The values of standard percentage deviations for NM, VDM, JM, EM, IM, CFT, FLT, and PFPT models are in the range of 0.3–1.4, 0.3–1.4, 0.3–1.1, 0.3–2.7, 0.5–1.2, 0.2–1.4, 0.4–1.2, and 0.4–1.2%, respectively. Considering the overall results, the FLT model predicts the most accurate values for speed of sound while the EM model gives the least accurate values. </span