Liquid Densities and Excess Quantities for the Green Esterification Process

Abstract

Liquid densities of deep eutectic solvents (DESs) such as choline chloride + glycerol {[ChCl]­[Gly]}, choline chloride + acetic acid {[ChCl]­[AA]}; ionic liquids (ILs), such as 1-ethyl-3-methylimidazolium hydrogen sulfate {[EMIM]­[HSO4]}, 1-ethyl-3-methylimidazolium ethyl sulfate {[EMIM]­[EtSO4]}, and 1-butyl-3-methylimidazolium acetate {[BMIM]­[Ac]}; and mixture of DESs + ILs as well as organic mixtures, such as n-butyl acetate + butanol and n-butyl acetate + acetic acid were measured at different temperatures from 293.15 to 343.15 K with an increase of 5 K. From this measured density, isobaric expansivity, excess molar volume, partial molar volume, excess partial molar volume, and apparent molar volume were calculated to understand and characterize the solution behavior as well as solvent–solvent interactions for the entire mole fraction at different temperatures. The excess molar properties showing positive deviation for DESs + ILs system, which indicates a creation of volume in the binary mixtures and disruption of H-bonds in the solution environment. Further, the sign and magnitude of all of the studied binary systems gave a good estimate of the attractive and disruptive interactions, chemical aggregation, H-bond formation, salt (choline chloride)–H (imidazolium) interaction, and salt (choline chloride)–O (acetate anion) interaction between those two components in the binary mixtures. The Redlich–Kister equation was used to fit the excess molar volume data and their corresponding regression coefficients (R 2) were also found. The σ-profile and σ-potential for the compounds in the present study have been generated and analyzed by means of specific molecular interactions between all of the studied compounds using the conductor like screening model for real solvents model.

Deep eutectic solvents on extraction of bisphenol A from water matrices: COnductor like Screening MOdel for Real Solvents prediction and experimental validation

“…This is an indication of the presence of strong ion‐solvent interaction in the binary mixture which is strengthened at lower temperatures. This type of behavior is also reported by Rajendran Startha Christabel et al 47 for several ILs and DESs + organic solvent systems. The regression coefficient values obtained with the linear fit were above 0.98 for all the binary mixtures which imply a better fit.…”

“…Also, the negative values indicate that the temperature does not show a significant influence of the volumetric expansion of this range. Likewise, the positive values in other mixtures indicate that the temperature has significant influence between the unlike molecules than like–like molecules in the mixtures 47 …”

“…Isobaric expansion (α) provides the knowledge of the temperature and pressure dependence for the physical–chemical properties and volume expansion of a component in the solution. The DESs, in general, do not expand appreciably in the temperature range of 293.15 to 343.15 K due to their high thermal stability nature 47 . From the obtained density data, the temperature dependence of the isobaric expansion coefficient was derived at different temperatures using the following equation; where α, ρ, and T denote the isobaric expansion coefficient of the mixture, density and temperature, respectively.…”

Investigation of molecular interaction, performance of green solvent in esterification of ethanol and acetic acid at 298.15 K and at 1 atm

“…All the chemical species used in this work were listed in Table 1. The detailed procedure for the synthesis of [ChCl][Gly] and [ChCl][HAc] were given in literature 10–13 . The molecular interaction of choline chloride (HBA) with glycerol and/or acetic acid forming deep eutectic solvent were represented in Table S3.…”

Comments on “Experimental and theoretical investigation of molecular interaction and molecular polarity of organic solvent with ionic liquids and deep eutectic solvents at T (298.15–343.15) K and 1 atm”

“…The error in the mathematical expressions used by Ramalingam and coworkers 1 in calculating their apparent molar volumes is that the algebraic sign on the right‐hand side of Equations and should be a plus sign, rather than a negative sign. The error likely propagated from earlier papers in the Journal of Chemical and Engineering Data 2 and South African Journal of Chemical Engineering 3 . Errors in published papers often become propagated in the literature unless the errors are identified and corrected.…”