Surface Tension Deviations Research Articles

Experimental and theoretical study of surface tension of binary mixtures of (n-alkyl acetates + heptane, benzene, and toluene)

Surface properties of binary mixtures of (n-alkyl acetates + heptane, benzene, and toluene) have been measured by surface tension method at T = 298.15 K and atmospheric pressure. Also, the surface tension has been predicted based on the Suarez method. This method combines a model for the description of surface tension of liquid mixtures with a group contribution method for the calculation of activity coefficient. The mean relative standard deviations obtained from the comparison of experimental (measured) and calculated surface tension values for the eight binary systems are less than 1.5%, which leads to concluding that the model shows a good accuracy in different situations in comparison with other predicted equations. In addition, the relative Gibbs adsorption and the surface mole fraction have been evaluated using this model. The surface tension deviations were calculated from experimental results and have been fitted to the Redlich–Kister type polynomial relation.

Surface Properties of Binary Mixtures of Ethylene Glycol with a Series of Aliphatic Alcohols (1-Pentanol, 1-Hexanol, and 1-Heptanol)

Surface tensions of binary mixtures of ethylene glycol and a homologous series of aliphatic alcohols (1-pentanol, 1-hexanol, and 1-heptanol) were measured as a function of composition using the ring detachment method in the temperature range between (298.15 and 318.15) K. Temperature influence on the behavior of surface tensions and surface properties of binary mixtures has often been used to obtain information about solute structural effects on ethylene glycol. Values of surface tension were correlated with temperature and mole fraction. The experimental data have been used to calculate the surface tension deviation, δσ, as a function of mole fraction, and values obtained are fitted to the Redlich−Kister polynomial equation to obtain the coefficients and the standard errors. The maximum deviation was in both cases always less than 0.5 %. The temperature dependence of σ at fixed composition of solutions was used to estimate surface enthalpy, Hs, and surface entropy, Ss.

Excess Molar Volumes and Surface Tensions of 1,2,4-Trimethylbenzene and 1,3,5-Trimethylbenzene with Isopropyl Acetate and Isobutyl Acetate at (298.15, 308.15, and 313.15) K

Densities and surface tensions for the binary mixtures of 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene with isopropyl acetate and isobutyl acetate have been measured over the whole composition range. The measurements were made under normal atmospheric pressure and at the temperatures (298.15, 308.15, and 313.15) K. The excess molar volumes and surface tension deviations are derived from the experimental data. The excess molar volumes for all the binary systems are positive, and the surface tension deviations are negative.

Effect of Relative Humidity of Air on Density, Apparent Molar Volume, Viscosity, Surface Tension, and Water Content of 1-Ethyl-3-methylimidazolium Ethylsulfate Ionic Liquid

The effect of relative humidity (RH) of air on the water content, density, apparent molar volume, dynamic viscosity, and surface tension of the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate has been studied. Physical property measurements were conducted at a temperature of 298.15 K, at atmospheric pressure, and in a RH range of (0 to 100) %. The experimental data were fit to first- and third-order polynomials that relate the physical properties with the relative humidity of air and the water content of [emim][EtSO4] with correlation coefficients higher than 0.9. The apparent molar volume was fit by the Redlich−Mayer equation with a relative standard deviation (σ) less than 2 cm3·mol−1. Excess molar volumes, viscosity, and surface tension deviations of a mole fraction average were calculated, and a second- and third-order Redlich–Kister polynomial was applied (σ equal to 0.01 cm3·mol−1, 0.5 mPa·s, and 0.6 mN·m−1, respectively).

Surface Tension of Binary Mixtures of N-Methyldiethanolamine and Triethanolamine with Ethanol

Surface tensions of binary mixtures of N-methyldiethanolamine and triethanolamine with ethanol were determined at (15 to 40) °C over the entire range of concentrations to analyze the influence of both variables. The Redlich–Kister equation was employed to fit surface tension deviation obtained from experimental values.

Study of the Temperature Dependence of Surface Tensions of Some Alkanol + Hexane Mixtures

Surface tensions of binary mixtures of ethanol, 1-butanol, or 2-butanol with hexane have been measured in the temperature range 283.15 K to 313.15 K with a drop volume tensiometer. The corresponding surface tension deviations have been calculated and correlated. Using the temperature dependence of surface tensions, the entropy change and enthalpy change of surface formation per unit area were evaluated at 298.15 K.

Excess Molar Volumes and Surface Tensions of 1,2,4-Trimethylbenzene and 1,3,5-Trimethylbenzene with 1,1-Diethoxyethane and 2,2-Dimethoxypropane at (298.15, 308.15, and 313.15) K

Densities and surface tensions for binary mixtures of 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene with 1,1-diethoxyethane and 2,2-dimethoxypropane have been measured over the whole concentration range. Measurements were made under normal atmospheric pressure at (298.15, 308.15, and 313.15) K. The experimental data are used to calculate the excess molar volumes and the surface tension deviations, respectively.

Densities and Surface Tensions of Propyl Acetate + Xylenes or + Ethylbenzene from (298.15 to 308.15) K

Densities and surface tensions for binary systems of (propyl acetate + o-xylene, + m-xylene, + p-xylene, + ethylbenzene) were measured under normal atmospheric pressure over the entire mole fraction range from (298.15 to 308.15) K. The excess molar volumes V E and surface tension deviations δσ for the above systems were calculated and fitted to the Redlich−Kister polynomial equation. The V E for the systems of (propyl acetate + m-xylene, + ethylbenzene) are nearly zero, but for the systems of (propyl acetate + o-xylene, + p-xylene) are negative. The δσ values are negative for all of the four systems. The V E of the four systems hardly change with increasing temperature, but their absolute values of δσ decrease with increasing temperature.

Surface tension of binary mobile phases for liquid chromatography

The dependences of the surface tension of some binary mobile phases for normal and reversed-phase liquid chromatography on the volume fraction of modifiers are considered. The dependences are described by polynomial functions containing surface tensions of the initial components along with empirical coefficients. The compositions with extrema of surface tension deviations from additive values were determined.

Densities, surface tensions, and derived surface thermodynamics properties of (trimethylbenzene + propyl acetate, or butyl acetate) from T = 298.15 K to 313.15 K

Densities ( ρ) for binary systems of (1,2,4-trimethylbenzene, or 1,3,5-trimethylbenzene + propyl acetate, or butyl acetate) were determined at four temperatures (298.15, 303.15, 308.15, and 313.15) K over the full mole fraction range. The excess molar volumes ( V E) calculated from the density data show that the deviations from ideal behaviour in the systems (all being positive, excepting 1,2,4-trimethylbenzene + butyl acetate system) become more positive with the temperature increasing. Surface tensions ( σ) of these binary systems were measured at the same temperatures (298.15, 303.15, 308.15, and 313.15) K by the pendant drop method, the surface tension deviations ( δσ) for all system are negative, and decrease with the temperature increasing. The V E and δσ are fitted to the Redlich–Kister polynomial equation. Surface tensions were also used to estimate surface entropy ( S σ ) and surface enthalpy ( H σ ).

Density and Surface Tension Variation with Temperature for Heptane + 1-Alkanol

New experimental densities and surface tensions for binary mixtures of {heptane + 1-butanol, + 1-hexanol, and + 1-octanol} in a temperature range of (288.15, 293.15, 298.15, 303.15, and 308.15) K are reported for the whole composition range. Densities were measured with an Anton Paar DMA 4500 densimeter. Surface tensions were measured using a Lauda TVT2 automated tensiometer, which uses the principle of the pending drop volume. The experimental data of pure liquids and mixtures have been used to calculate excess molar volumes and surface tension deviations of the mixtures as a function of mole fractions.

Densities and Surface Tensions of Trimethylbenzene + Dimethyl Carbonate or + Diethyl Carbonate at 298.15 K and 313.15 K

Densities and surface tensions for binary systems of (1,2,4-trimethylbenzene or 1,3,5-trimethylbenzene + dimethyl carbonate or diethyl carbonate) have been measured under normal atmospheric pressure over the entire mole fraction range at 298.15 K and 313.15 K. The excess molar volumes and the surface tension deviation have been calculated. The excess molar volumes and the values of the surface tension deviation are fitted to the Redlich−Kister polynomial equation. The excess molar volumes for all the binary systems are positive over the whole composition range, and the surface tension deviations are negative.

Density and Surface Tension of Binary Mixtures of Acetonitrile + 1-Alkanol at 293.15 K

Surface tension and density of {acetonitrile + methanol, ethanol, 1-propanol, 1-butanol, or 1-pentanol} at the temperature 293.15 K and normal atmospheric pressure have been measured as a function of mole fraction. The Redlich−Kister polynomial equation was fitted to each of the experimental surface tension deviation and excess molar volume results. Using the resulting polynomial equations, the surface tension deviations and the excess molar volumes (Δσ, ) were calculated over the entire composition range. The results obtained are discussed and interpreted in terms of the type and nature of the specific intermolecular interaction between the components.

Density and surface tension variation with temperature for n-nonane + 1-hexanol

New experimental densities and surface tensions for n-nonane + 1-hexanol at 288.15, 298.15 and 308.15 K are reported. Densities were measured with an Anton Paar DMA 4500 densimeter, and surface tensions using a Lauda TVT2 automated tensiometer, which uses the principle of the pending drop volume. The experimental data of pure liquids and mixtures have been used to calculate excess molar volumes and surface tension deviations of n-nonane + 1-hexanol as a function of mole fractions. A comparative study of these properties together with those available in the literature for the n-alkane + 1-alkanol mixtures has been performed. In addition, the magnitude of these experimental quantities is discussed in terms of the nature and type of intermolecular interactions in binary mixtures.

Excess Molar Volumes and Surface Tensions of Trimethylbenzene + Ethylene Glycol Ester at 298.15 K and 313.15 K

Densities for binary systems of [1,2,4-trimethylbenzene or 1,3,5-trimethylbenzene + ethylene glycol monomethyl ether (2-methoxyethanol) or ethylene glycol dimethyl ether (1,2-dimethoxyethane)] have been determined under normal atmospheric pressure at 298.15 K and 313.15 K over the entire mole fraction range. The excess molar volumes were calculated. Surface tensions of these binary systems have been measured at 298.15 K and 313.15 K by the pendant drop method, and the values of the surface tension deviation were also derived. The excess molar volumes and the values of the surface tension deviation are fitted to the Redlich−Kister polynomial equation. The excess molar volumes for all the binary systems are positive over the whole composition range, and their surface tension deviations are negative.

Densities, Surface Tensions, and Refractive Indexes of Propyl Propanoate + Hexane + m-Xylene at 298.15 K

This paper reports experimental densities, surface tensions, and refractive indexes of the ternary system (propyl propanoate + hexane + m-xylene) at the temperature 298.15 K and atmospheric pressure over the whole composition range. Also, the corresponding binary mixtures not published before are presented. The excess molar volumes, surface tension deviations, and changes in the refractive index on mixing have been calculated. Finally, we will compare the experimental data of surface tension and refractive index with different theoretical and empirical approximations.

Surface Behavior of the 1-Bromobutane with Isomeric Butanol Mixtures

Surface tensions of the 1-bromobutane with isomeric butanol mixtures were measured in the temperature range 283.15 K (or 298.15 K for 2-methyl-2-propanol) to 313.15 K with a drop volume tensiometer, and the corresponding surface tension deviations were calculated. Using this information together with bulk thermodynamic properties a thermodynamic study on surface formation was presented. This study includes the calculation of excess surface compositions and excess properties of surface formation.

Thermophysical study of 1,4-dioxane with cycloalkane mixtures

Densities, refractive indices, and surface tension for the binary mixtures 1,4-dioxane with cyclopentane or cylohexane have been determined at ambient pressure and at T = (283.15, 298.15, and 313.15) K. Excess volumes and refractive index and surface tension deviations have been calculated from the experimental data. Several relations between the thermophysical properties studied here have been tested using our experimental results.

Thermophysical properties of the binary mixtures of 2-methyl-tetrahydrofuran with benzene and halobenzenes

Densities, speeds of sound, heats of mixing, refractive indices and surface tensions for the binary mixtures of 2-methyl-tetrahydrofuran with benzene, fluorobenzene and chlorobenzene have been determined at atmospheric pressure at the temperature of 298.15 K. Excess molar volumes, excess isentropic compressibilities, excess molar enthalpies, refractive index deviations and surface tension deviations have been calculated from the experimental data and fitted to a Redlich–Kister polynomial function. The Prigogine–Flory–Patterson theory has been used to predict the excess thermophysical properties of the binary mixtures.

Study of the Surface Tension of Chlorocyclohexane or Bromocyclohexane with Some Cyclic Ethers

Experimental surface tensions for mixtures formed by chlorocyclohexane or bromocyclohexane and a cyclic ether (tetrahydropyran, tetrahydrofuran, 2-methyltetrahydrofuran, or 2,5-dimethyltetrahydrofuran) have been measured with a drop volume tensiometer at temperatures of 298.15 K and 313.15 K. The surface tension deviations for the binary mixtures, that is, for each mixture, the deviation of the surface tension from a mole fraction average, have been calculated from the experimental data.