Physicochemical studies on the effect of protic ionic liquid (PIL) on monomer unit of cellulose are needed to understand the structural interactions taking place between carbohydrate polymers and ILs. Therefore, we have studied the volume and enthalpy of dilution of D(+)-glucose and D(+)-xylose in water and in (0.10, 0.15, 0.20, and 0.25) mol kg-1 aqueous solutions of newly synthesized N-methyl-2-pyrrolidonium formate; [NMP][For] and N-methyl-2-pyrrolidonium propionate; [NMP][Pro] at T=(288.15-318.15) K. Further, nuclear magnetic resonance spectroscopy (NMR) has also been employed to understand the nature of interactions occurring in ternary solutions (PIL + water + monosaccharides). The dominance of hydrophobic type of interactions between monosaccharides and PILs in aqueous solutions has been observed. The results obtained from thermophysical and spectroscopic techniques complement each other and can be used to understand key factors determining the cellulose dissolution process. © 2016 Elsevier B.V.

Ramesh L. Gardas

Department Of Chemistry

Somenath Panda

cellulose

glucose

Ionic liquids

Liquids

Magnetic Resonance Spectroscopy

Solutions

Spectroscopic analysis

CARBOHYDRATE POLYMERS

CELLULOSE DISSOLUTIONS

Heat of dilution

Partial molar volume

Physicochemical studies

PROTIC IONIC LIQUIDS

Spectroscopic technique

STRUCTURAL INTERACTIONS

Nuclear magnetic resonance spectroscopy

dilution

nuclear magnetic resonance

xylose

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Fluid Phase Equilibria

The precise and accurate thermophysical properties determination of ionic liquid (IL)-solvent binary system is needed for understanding the molecular interactions occurring between these components. The nature of ion-ion and ion-solvent interactions can be studied either experimentally on the basis of apparent and partial molar properties and corresponding infinite dilution properties or by computational studies. In this regard, we have measured the thermodynamic properties of binary aqueous solutions containing newly synthesized N-methylpyrrolidone based protic ionic liquids (PILs) in the temperature range (288.15–328.15) K and at ambient pressure. Experimentally measured density and speed of sound data have been used to calculate the infinite dilution partial molar properties and the corresponding empirical parameters through the Redlich-Mayer type of equation. It is observed that the studied PILs interacts strongly with water, however the ion-solvent interactions decreases with increase in anionic chain length and increase in temperature. Observed intra-ionic and inter-ionic interactions in studied aqueous ionic liquid mixtures were also supported by Density Functional Theory (DFT) calculations. © 2017 Elsevier B.V.

Understanding ion-ion and ion-solvent interactions in aqueous solutions of NMP based protic ionic liquids through partial molar properties and DFT calculations

In order to analyze the extent of solvation behaviour and stability of ascorbic acid (AA) in water or aqueous ionic liquid (IL) solutions, the knowledge of their thermodynamic properties is prerequisite which gives an appropriate idea about interactions involved in solutions. In addition, experimental and derived thermodynamic data is essential in effective process and product design involving these systems. In this report, we studied the volumetric and acoustic properties of AA in aqueous solution of synthesized IL, [HxTzm][CF3SO3] i.e. (1-Hexyl-4-(4-sulfobutyl)-1H-1,2,4-triazol-4-ium trifluoromethanesulfonate) in temperature range of (293.15–328.15) K and at atmospheric pressure. Further, the experimentally measured thermodynamic properties were used to calculate apparent molar and partial molar properties, which elucidate the solvation behaviour of AA in presence of studied IL. Further, on the basis of the structural interaction model, various type of interactions which is stirring between AA and IL have been discussed in terms of partial molar properties at infinite dilution, transfer parameters and pair and triplet interaction coefficients. © 2017 Elsevier B.V.

Journal of Molecular Liquids

Exploration of the solvation behaviour of ascorbic acid in aqueous solutions of 1,2,4-triazolium based ionic liquid

The densities, ρ and speeds of sound, u of d(-)-ribose in aqueous solutions of ammonium based protic ionic liquid i.e., 3-hydroxypropylammonium acetate (3HPAAc) have been measured at temperatures (298.15-318.15) K and at atmospheric pressure. These experimental data were used to calculate apparent molar volumes, V<inf>2,φ</inf>, apparent molar isentropic compressibilities, K<inf>s,2,φ</inf>, infinite dilution partial molar volumes, V<inf>2</inf>°, and partial molar isentropic compressibilities, K°<inf>s,2</inf> and the corresponding volumes of transfer (Δ<inf>t</inf>V<inf>2</inf>° and Δ<inf>t</inf>K°<inf>s,2</inf>). Both Δ<inf>t</inf>V<inf>2</inf>° and Δ<inf>t</inf>K°<inf>s,2</inf> values were found to be positive, which increase with cosolute (3HPAAc) concentration and temperature, which indicate the presence of hydrophilic-ionic types of interactions between d(-)-ribose (Rib) and ions of 3HPAAc. Various derived parameters such as expansion coefficients, hydration numbers, pair and triplet interaction coefficients for Rib in aqueous 3HPAAc solutions have also been evaluated and discussed. © 2015 Elsevier B.V. All rights reserved.

Thermochimica Acta

Effect of protic ionic liquid on the volumetric properties of ribose in aqueous solutions

In this work, a new series of low viscous protic ionic liquids based on N-methylpyrrolidone cation and carboxylate anions with different chain length has been synthesized and characterized. Density, speed of sound and viscosity have been measured for these ionic liquids in the temperature range from 293.15 to 343.15. K. The density data have been fitted to linear equation as well as correlated with group contribution method developed by Gardas and Coutinho. From the density correlation, molecular volume data for cation and anion constituents of studied ionic liquids have been proposed. By using experimental density and speed of sound data, the isentropic compressibility, coefficient of thermal expansion, standard entropy, intermolecular free length and lattice energy have been calculated for studied ionic liquids. Viscosity data were correlated with the Vogel-Tammann-Fulcher equation. To understand the nature of the ionic liquids and structure-property relationship, the effect of anion alkyl chain length has been studied and correlated. Ionic liquids studied in this work are comparatively cheaper in price and can be promising in bio-macromolecule solubilization and other commercial fields. © 2014 Elsevier B.V.

Measurement and correlation for the thermophysical properties of novel pyrrolidonium ionic liquids: Effect of temperature and alkyl chain length on anion

In this work, we report the densities, ρ and apparent molar volumes of imidazolium based ionic liquid (1-butyl-3-methylimidazolium bromide, [Bmim]Br) in water and in aqueous solutions of two pentoses namely d(-)-ribose (Rib) and d(-)-arabinose (Arb) at different temperatures (288.15 to 318.15) K and at atmospheric pressure. The infinite dilution partial molar volume, V<inf>2</inf>° and empirical parameters (S<inf>v</inf> and B<inf>v</inf>) were evaluated by using Redlich-Mayer type of equation. The volume of transfer (Δ<inf>t</inf>V<inf>2</inf>°) for [Bmim]Br from water to aqueous monosaccharide solutions were found to be positive and decrease in the following order: Rib > Arb. The S<inf>v</inf>, B<inf>v</inf> Δ<inf>t</inf>V<inf>2</inf>° and other parameters such as expansion coefficients and interaction coefficients were discussed in terms of interactions occurring between monosaccharides and ionic liquid. Modulation of volumetric properties of BmimBr in mixed aqueous solutions has also been discussed in relation to the stereochemistry of monosaccharides. © 2015 Elsevier B.V. All rights reserved.

Volumetric properties of 1-butyl-3-methylimidazolium bromide in aqueous solutions of d(-)-ribose and d(-)-arabinose at different temperatures

Densities, ρ, and speeds of sound, u, of two disaccharides (D-(+)-maltose and D-(+)-cellobiose) in water and in the presence of protic ionic liquid (PIL) (i.e., benzyldimethylammonium acetate, BDMAAc) were measured at different temperatures (288.15-318.15) K at atmospheric pressure. These data were used to calculate the apparent molar volume, apparent molar isentropic compressibility, infinite dilution partial molar volume, infinite dilution partial molar isentropic compressibility, and corresponding transfer parameters (Δ<inf>t</inf>V°<inf>2</inf> and Δ<inf>t</inf>K°<inf>s,2</inf>) for disaccharides from water to aqueous PIL solutions. The effect of BDMAAc on the basic taste quality of disaccharides was evaluated from apparent specific volume and apparent specific isentropic compressibility, as these parameters are grouped in various taste qualities. © 2015 American Chemical Society.

Journal of Chemical and Engineering Data

Volumetric Properties of Disaccharides in Aqueous Solutions of Benzyldimethylammonium Acetate as a Function of Temperature

In this work, apparent molar volume and apparent molar isentropic compressibility of sucrose in aqueous solutions of ammonium based protic ionic liquid (PIL) have been evaluated from experimentally determined values of density and speed of sound at T = (293.15, 298.15, 303.15, 308.15, 313.15 and 318.15) K and at 101.3 kPa. The types of interactions occurring between sucrose and PIL (3-hydroxypropylammonium formate; 3HPAF) in aqueous solutions were studied and are discussed on the basis of infinite dilution partial molar volumes, V2°, and isentropic compressibility, Ks,2°, transfer volume and compressibility (Δ<inf>t</inf>V2° and Δ<inf>t</inf>Ks,2°), expansion coefficients, [(δV2°/δT)<inf>P</inf> and (δ2V2°/δT2)<inf>P</inf>], interaction coefficients, (Y<inf>AB</inf> and Y<inf>ABB</inf>) and hydration numbers, N<inf>w</inf>. Further, apparent specific volume, ASV and apparent specific isentropic compression, ASIC were determined and analysed to evaluate the effect of PIL on the basic taste quality of sucrose. © 2015 Elsevier Ltd. All rights reserved.

Journal of Chemical Thermodynamics

Volumetric and ultrasonic properties of ternary (sucrose + water + protic ionic liquid) solutions

Solvation behavior of monosaccharides in aqueous protic ionic liquid solutions: Volumetric, calorimetric and NMR spectroscopic studies

Journal	Data powered by TypesetFluid Phase Equilibria
Publisher	Data powered by TypesetElsevier B.V.
ISSN	03783812
Open Access	No