Surface Tension Deviations Research Articles

Isothermal Vapor + Liquid Equilibrium and Thermophysical Properties for 1-Butyl-3-methylimidazolium Bromide + 1-Butanol Binary System

Experimental isothermal vapor + liquid equilibrium (VLE) data are reported for the binary mixture containing 1-butyl-3-methylimidazolium bromide ([bmim]Br) + 1-butanol at three temperatures, 353.15, 363.15, and 373.15 K, in the range of 0–0.321 liquid mole fraction of [bmim]Br. Additionally, refractive index measurements have been performed at two temperatures, 298.15 and 308.15 K in the whole composition range. Densities, excess molar volumes, surface tensions, and surface tension deviations of the binary mixture were predicted by Lorenz–Lorentz (nD–ρ) mixing rule. Dielectric permittivities and their deviations were evaluated by known equations. Vapor + liquid equilibrium data were correlated with the Wilson thermodynamic model while refractive index data were correlated by the 3-parameters Redlich–Kister equation. The studied mixture presents positive abatement from Raoult’s law. Similarly, positive refractive index deviations are obtained. The VLE data may be used in separation processes design, and the thermophysical properties may be used as key parameters in specific applications.

Density, Viscosity, Refractive Index, and Surface Tension for Six Binary Systems of Adamantane Derivatives with 1-Heptanol and Cyclohexylmethanol

Measurements on densities (ρ), viscosities (η), and refractive indices (nD) from (293.15 to 333.15) K and at 0.1 MPa along with the surface tensions (γ) at 298.15 K and 0.1 MPa for binary mixtures of 1,3-dimethyladamantane (1,3-DMA), 1-ethyladamantane (1-EA), and 1,3,5-trimethyladamantane (1,3,5-TMA) with 1-heptanol or cyclohexylmethanol have been carried out over the entire composition range. The experimental data are used to calculate the excess molar volumes (VmE), viscosity deviations (Δη), molar refraction deviations (ΔΦR), and surface tension deviations (Δγ). The VmE, Δη, ΔΦR, and Δγ values have been fitted to the Redlich–Kister polynomial equation. From these excess or deviation functions, the molecular interactions and nonideality of the binary systems are discussed. The results are expected to provide fundamental data for understanding the properties of adamantane derivatives as potential components and the composition optimization of new high energy-density hydrocarbon fuels.

Thermodynamic study of the surface of liquid mixtures containing pyridinium-based ionic liquids and alkanols

Surface tension for seven binary mixtures containing a pyridinium-based ionic liquid (1-propylpyridinium tetrafluoroborate, 1-butylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium tetrafluoroborate, or 1-butyl-4-methylpyridinium) and a short chain alkanol (methanol or ethanol) were determined at the temperatures: (293.15, 303.15, 313.15, and 323.15)K. From these data, the surface tension deviations were calculated. These deviations were correlated using a Redlich–Kister polynomial expansion. Moreover, relative adsorptions of alkanol at the (air+liquid) interface were calculated from the Gibbs isotherm.

Equilibrium surface tension and the interaction energy of DMSO with tert-butyl alcohol or iso-amyl alcohol at various temperatures

Surface tension of binary mixtures of tert-butyl alcohol (TBA) and iso-amyl alcohol (IAA) with DMSO (dimethyl sulfoxide) were measured over the entire concentration range at pressure of 82.5kPa at temperatures between (298.15 and 328.15)K. Correlating the surface tension and surface tension deviation of the above mentioned binary systems was performed with empirical and thermodynamic based models. The average relative error obtained from the comparison of experimental and calculated surface tension values for the two binary systems with five models at various temperatures is less than 2%. The effect of temperature on the interaction energy values in binary mixtures has been used to obtain information about solute structural effects on DMSO. Also, the experimental data were used to evaluate the nature and type of intermolecular interactions in binary mixtures.

Measurement and correlation of thermodynamic properties for the binary and ternary mixtures containing 2-propanol, 1,3-propanediol, and water

Thermodynamic properties, such as densities, viscosities, and surface tensions of the ternary system (2-propanol+1,3-propanediol+water) at T=298.15K and its constituent binary systems (2-propanol+1,3-propanediol, 2-propanol+water, and 1,3-propanediol+water) at T=(298.15, 308.15, 318.15, and 328.15)K were measured under atmospheric pressure. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic Ubbelholde capillary viscometer. Surface tensions were determined by the Wilhelmy-plate method. From these experimental data, the excess molar volumes (VE), deviations in viscosity (οη), and deviations in surface tension (οϿ) were derived. The values of binary VE and οη were correlated with the Redlich⿿Kister equation. A simple equation based on Connors and Wright was derived for the correlation of binary οϿ data. The values of ternary VE, οη, and οϿ were fitted to a variable-degree polynomial equation and compared with those predicted from binary data using the equations of Kohler, Colinet, Jacob⿿Fitzner, Scatchard et al., Tsao⿿Smith, and Toop. The values of VE and οη were used to discuss the nature of mixing behaviors between mixture components.

Effect of temperature and chain length on the viscosity and surface tension of binary systems of N,N-dimethylformamide with 1-octanol, 1-nonanol and 1-decanol

Viscosity and surface tension of binary systems of N,N-dimethylformamide DMF with higher 1-alkanols (C8–C10) were measured at atmospheric pressure and four different temperatures over the entire range of mole fraction. The experimental measurements were used to calculate the deviations in viscosity and surface tension. Furthermore, the excess Gibbs free energy of activation, surface enthalpy and surface entropy of the (DMF+1-alkanols) binary mixtures were determined. In addition, the deviation and excess properties were fitted to the method of Redlich–Kister (R–K) polynomial. Viscosity data of the binary systems were correlated with three different expressions (Grunberg and Nissan, the three-body, and four-body McAllister). The effects of the chain length of the higher 1-alkanols and temperature were investigated.

Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes

For a comprehensive understanding of the properties of 1,3-dimethyladamantane (1,3-DMA) as a new potential candidate of high energy-density hydrocarbon fuels, densities, viscosities, surface tensions, and refractive indices for binary mixtures of 1,3-DMA with each of four C10 alkanes, n-decane, butylcyclohexane, decalin, and exo-tetrahydrodicyclopentadiene (JP-10), are determined over the whole composition range at different temperatures ranging from (293.15 to 363.15) K and atmospheric pressure (0.1 MPa). The excess molar volume (VmE), the viscosity deviation (Δη), the surface tension deviation (Δγ), and the refractive index deviation (ΔnD) for these binary systems are calculated. All of the VmE values are negative over the whole composition range for these systems, and they show slight changes against the temperature. The Δη values for the systems except 1,3-DMA + JP-10 are negative, and the absolute values decrease obviously with rising temperature. The Δγ gives clearly negative values for the system o...

Surface Tension Measurements for Seven Imidazolium-Based Dialkylphosphate Ionic Liquids and Their Binary Mixtures with Water (Methanol or Ethanol) at 298.15 K and 1 atm

Surface tension data were measured by the Wilhelmy plate method for the binary mixtures containing an ionic liquid of the imidazolium dialkylphosphate family and water (methanol or ethanol) at 298.15 K and atmospheric pressure. The enthalpy of vaporization Δ1gHmo and Hildebrand solubility parameter δH for the pure components are estimated from the experimental data, and a perfect correlation is found between surface tension and specific cohesive energy per unit surface area for the imidazolium dialkylphosphate series ionic liquids (ILs). The surface tension as well as the surface tension deviation against the solution composition shows a remarkable difference between the mixtures of an IL with water and with alcohols, which is interpreted qualitatively by the δH values of the corresponding pure components. Some ILs act as a surfactant in aqueous solution, but most of them more like a conventional nonelectrolyte component in the alcoholic solutions.

Effect of temperature and composition on the density, viscosity surface tension and excess quantities of binary mixtures of 1-ethyl-3-methylimidazolium tricyanomethanide with thiophene

Thermal properties of the ionic liquid (IL) 1-ethyl-3-methylimidazolium tricyanomethanide, ([EMIM][TCM]), measured by the Differential scanning calorimetry (DSC) as glass transition temperature (Tg,1), heat capacity change at glass transition temperature (ΔCp(g),1), melting temperature (Tfus), enthalpy of melting (ΔHfus), phase transition temperature (Ttr), enthalpy of phase transition (ΔtrH) and decomposition temperature (Td) were presented. The density and viscosity for the binary mixtures containing [EMIM][TCM] and thiophene at six temperatures (298.15, 308.15, 318.15, 328.15, 338.15 and 348.15K) and ambient pressure were reported. The density and viscosity as a function of temperature were tested by an empirical second-order polynomial and by the Vogel–Fucher–Tammann equation. The density and viscosity variations with compositions were described by polynomials. Excess molar volumes were described by the Redlich–Kister polynomial expansion. Viscosity deviations were calculated and correlated by the Redlich–Kister polynomial expansions. The surface tensions of pure ionic liquid and binary mixtures of [EMIM][TCM] and thiophene were measured at atmospheric pressure at five temperatures (298.15, 308.15, 318.15, 328.15, and 338.15K). The surface tension deviations were calculated and correlated by the Redlich–Kister polynomial expansion. The temperature dependence of interfacial tension was used to evaluate the excess surface energy, the surface enthalpy, the critical temperature, parachor and speed of sound for pure ionic liquid. These measurements have been provided to complete information of the influence of temperature on physico-chemical properties for the selected IL, which was chosen as a possible new entrainer in the separation of sulfur compounds from fuels. A qualitative analysis on these quantities in terms of molecular interactions is reported. The obtained results indicate that ionic liquid interactions with alcohols are strong dependent on the special trend of packing effects and hydrogen bonding of this ionic liquid with polar solvent.

Surface tensions of binary mixtures of ionic liquids with bis(trifluoromethylsulfonyl)imide as the common anion

While values for thermophysical properties of ionic liquids are becoming widely available, data for ionic liquid mixtures are still scarce. In an effort to overcome this limitation and understand the behavior of ionic liquid mixtures, novel data for the surface tension of mixtures composed of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C4mim][NTf2], with other ionic liquids with a common anion, namely 1-butyl-2,3-dimethylimidazolium, [C4C1mim]+, 3-methyl-1-propylpyridinium, [C3mpy]+, 1-methyl-1-propylpyrrolidinium, [C3mpyr]+, and 1-methyl-1-propylpiperidinium, [C3mpip]+, were measured at T=298.2K and atmospheric pressure over the entire composition range. From the surface tension deviations derived from the experimental results, it was possible to infer that the cation alkyl chain length of the second ionic liquid constituting the mixture has a stronger influence in the ideal mixture behavior than the type of family the ionic liquid cation belongs to. The Gibbs adsorption isotherms, estimated from the experimental values, show that the composition of the vapor–liquid interface is not the same as that of the bulk and that the interface is richer in the ionic liquid with the lowest surface tension, [C4mim][NTf2].

Surface Tension of Dialkyl Carbonates + (Alkanes or 1,4-Dimethylbenzene) and 1,4-Dimethylbenzene + Alkanes Binary Mixtures at T = 308.15 K

New experimental surface tension data are reported for binary mixtures of dimethyl carbonate and diethyl carbonate with octane, decane, and 1,4-dimethylbenzene and 1,4-dimethylbenzene with octane and decane at 308.15 K and atmospheric pressure. These experimental results are compared with those reported in the literature at different temperature when they are available. The experimental results show that surface tension of these compounds depends systematically on temperature. The surface tension deviation calculated was fitted by the Redlich–Kister polynomial equation. The adjustable parameters obtained for each system are reported with the standard deviations between experimental and calculated values.

Alteration of biophysical activity of pulmonary surfactant by aluminosilicate nanoparticles

The influence of five different types of aluminosilicate nanoparticles (NPs) on the dynamic surface activity of model pulmonary surfactant (PS) (Survanta) was studied experimentally using oscillating bubble tensiometry. Bentonite, halloysite and montmorillonite (MM) NPs, which are used as fillers of polymer composites, were characterized regarding the size distribution, morphology and surface area. Particle doses applied in the studies were estimated based on the inhalation rate and duration, taking into account the expected aerosol concentration and deposition efficiency after penetration of NPs into the alveolar region. The results indicate that aluminosilicate NPs at concentrations in the pulmonary liquid above 0.1 mg cm−3 are capable of promoting alterations of the original dynamic biophysical activity of the PS. This effect is indicated by deviation of the minimum surface tension, stability index and the size of surface tension hysteresis. Such response is dependent on the type of NPs present in the system and is stronger when particle concentration increases. It is suggested that interactions between NPs and the PS must be related to the surfactant adsorption on the suspended particles, while in the case of surface-modified clay NPs the additional washout of surface-active components may be expected. It is speculated that observed changes in surface properties of the surfactant may be associated with undesired health effects following extensive inhalation of aluminosilicate NPs in the workplace.

Density and surface tension of binary mixtures of 1-ethyl-3-methylimdazolium nitrate with alcohols

Abstract New experimental data of densities and surface tensions are presented for the binary mixtures of the ionic liquid 1-ethyl-3-methyl imidazolium nitrate ([EMIM]NO 3 ) with methanol and ethanol. Measurements were performed at 298.15 K and atmospheric pressure, covering the whole composition range. Excess molar volumes V E and the surface tension deviations δγ have been determined. For the excess molar volumes of binary mixture, there is a region of negative V E at low IL mole fraction, passing through a minimum and then V E increases and becomes positive, showing maximum at higher IL mole fraction. It is shown that the surface tension deviations δγ of [EMIM]NO 3 + methanol system are positive but those of [EMIM]NO 3 + ethanol system are negative over the entire mole fraction range.

Surface Tension of Binary Mixtures of 1-Alkyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide Ionic Liquids: Experimental Measurements and Soft-SAFT Modeling

Ionic liquids have attracted a large amount of interest in the past few years. One approach to better understand their peculiar nature and characteristics is through the analysis of their surface properties. Some research has provided novel information on the organization of pure ionic liquids at the vapor-liquid interface; yet, a systematic study on the surface properties of mixtures of ionic liquids and their organization at the surface has not previously been carried out in the literature. This work reports, for the first time, a comprehensive analysis of the surface organization of mixtures of ionic liquids constituted by 1-alkyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide ionic liquids, [C(n)mim][NTf(2)]. The surface tension of mixtures composed of [C(4)mim][NTf(2)] + [C(n)mim][NTf(2)] (n = 1, 2, 5, 6, 8, and 10) was experimentally determined, at 298.2 K and atmospheric pressure, in the whole composition range. From the experimental data, the surface tension deviations and the relative Gibbs adsorption isotherms were estimated showing how the surface composition of an ionic liquid mixture differs from that of the liquid bulk and that the surface is enriched by the ionic liquid with the longest alkyl chain length. Finally, the soft-SAFT equation of state coupled with the density gradient theory (DGT) was used, for the first time, to successfully reproduce the surface tension experimental data of binary mixtures of ionic liquids using a molecular-based approach. In addition, the DGT was used to compute the density profiles of the two components across the interface, confirming the experimental results for the components distribution at the bulk and at the vapor-liquid interface.

Viscosity and surface tension of binary systems of N,N-dimethylformamide with alkan-1-ols at different temperatures

Viscosity η and surface tension σ were measured for binary mixtures of N,N-dimethylformamide DMF with pentan-1-ol, hexan-1-ol, and heptan-1-ol at T=(298.15, 303.15, 308.15, and 313.15)K and atmospheric pressure over the entire mole fraction range. Deviations in viscosity Δη and surface tension Δσ were calculated using experimental results. Moreover, the values of the excess Gibbs free energy of activation G∗E, surface enthalpy Hσ and surface entropy Sσ of these mixtures were determined. Viscosity measurements of the binary systems were correlated with Grunberg and Nissan, the three-body and four-body McAllister expressions. Viscosity deviation, surface tension deviation and excess Gibbs energy of activation functions were fitted to the method of Redlich–Kister (R–K) polynomial to estimate the coefficients and standard deviations. The effects of chain length of alkan-1-ols and temperature on the thermodynamic properties of binary systems were studied.

Densities, Viscosities, Refractive Indexes, and Surface Tensions for Mixtures of Ethanol, Benzyl Acetate, and Benzyl Alcohol

Densities, viscosities, refractive indexes, and surface tensions of the ternary system (ethanol + benzyl acetate + benzyl alcohol) at T = 303.15 K and its constituent binary systems (ethanol + benzyl acetate, ethanol + benzyl alcohol, and benzyl acetate + benzyl alcohol) at T = (293.15, 303.15, 313.15, and 323.15) K were measured under atmospheric pressure. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic microviscometer based on the rolling-ball principle. Refractive indexes were measured using a digital Abbe-type refractometer. Surface tensions were determined by the Wilhelmy-plate method. From these data, excess molar volumes, deviations in viscosity, deviations in refractive index, and deviations in surface tension were derived. The results for the binary and ternary systems were fitted to the Redlich–Kister equation and the Cilbuka equation, respectively. The excess molar volumes and deviations in viscosity are used to study the nature of mixing...

The Surface Tension of a Mixture System of Acetophenone + Isopropyl Benzene + Phenol at 283.15 K

Surface tensions and densities of binary (acetophenone + isopropyl benzene) and ternary (acetophenone + isopropyl benzene + phenol) mixtures were measured at 283.15 K and normal atmosphere using a platinum ring method and Mirage densitometer. The surface tension deviations and excess molar volumes (Δσ, V E m) were calculated from the experimental results in different molar fractions. The Redlich-Kister polynomial equation was fitted to the surface tension deviations and the excess molar volume results.

Surface tension of four binary systems containing (1-ethyl-3-methyl imidazolium alkyl sulphate ionic liquid + water or + ethanol)

In this work, we present surface tension experimental measurements for eight binary systems containing water or ethanol and an ionic liquid (IL) of the 1-ethyl-3-methyl imidazolium alkyl sulphate family, being the alkyl chain of the anion: ethyl, butyl, hexyl and octyl. Measurements were performed at the temperature of 25.0°C and atmospheric pressure. All four ILs are completely miscible with water and ethanol, but for a concentration range of the octyl sulphate IL aqueous system the mixture jellifies, and so it is not possible to measure its surface tension. These measurements allow us to study the influence of the anion size on the surface tension for the pure IL compounds, and the role of the two different solvents in the surface tension behaviour. Thus, we observe that it is completely different when mixed with water or with ethanol, as also happens in other mixtures with different ionic liquids. From the experimental data, we extract surface tension deviations using the most popular definition. The calculated deviations for the ethanol based system are fitted using the Redlich–Kister equation and a novel one previously reported by us. Furthermore, we have also calculated the reduced surface pressure for the aqueous mixtures, which is fitted with good agreement using a theoretical equation obtained from the Bahe–Varela pseudo-lattice model.

Thermodynamic properties of 1‐ETHYL‐3‐methylimidazolium methanesulphonate with aromatic sulphur, nitrogen compounds at T = 298.15–323.15 K and P = 1 bar

AbstractThis work investigates the ability of 1‐ethyl‐3‐methylimidazolium methanesulphate ([EMIM][MeSO3]) as a green and tuneable solvent for denitrification and desulphurisation studies. Experimental density, surface tension and refractive index data have been measured for the following systems: [EMIM][MeSO3] (1) + pyridine (2), [EMIM][MeSO3] (1) + pyrrole (2), [EMIM][MeSO3] (1) + quinoline (2), [EMIM][MeSO3] (1) + indoline (2), [EMIM][MeSO3] (1) + thiophene (2) and [EMIM][MeSO3] (1) + water (2) over the entire mole fraction of [EMIM][MeSO3] at T = 298.15–323.15 K and P = 1 bar. Further from experimental density, surface tension and refractive index, coefficient of thermal expansivity, excess molar volume, deviation of surface tension and refractive index deviation were also calculated. It was found that the heteroaromatic nitrogen/sulphur compounds are completely miscible in [EMIM][MeSO3]. The surface tension values were found to increase while the refractive index decreases with increasing mole fraction of [EMIM][MeSO3]. The experimental values for surface tension increased in the order: pyridine > thiophene > pyrrole > indoline > quinoline > water and for refractive index: pyridine > pyrrole > indoline > quinoline > thiophene > water. It was found that the composition of [EMIM][MeSO3] has a greater influence than temperature in deciding the surface, optical and thermodynamic properties for similar molecular interaction such as IL–thiophene and IL–pyrrole than dissimilar molecules such as IL–water. Further quantum chemical‐based COSMO‐RS tool was used to estimate the activity coefficient at different composition. © 2012 Canadian Society for Chemical Engineering

Effect of temperature and composition on the density, viscosity, surface tension, and thermodynamic properties of binary mixtures of N-octylisoquinolinium bis{(trifluoromethyl)sulfonyl}imide with alcohols

Density and viscosity were determined for the binary mixtures containing the ionic liquid N-octylisoquinolinium bis{(trifluoromethyl)sulfonyl}imide ([C8iQuin][NTf2]) and 1-alcohol (1-butanol, 1-hexanol, and 2-phenylethanol) at five temperatures (298.15, 308.15, 318.15, 328.15, and 338.15)K and ambient pressure. The density and viscosity correlations for these systems were tested by an empirical second-order polynomial and by the Vogel–Fucher–Tammann equation. Excess molar volumes were described by the Redlich–Kister polynomial expansion. The density and viscosity variations with compositions were described by polynomials. Viscosity deviations were calculated and correlated by the Redlich–Kister polynomial expansions. The surface tensions of pure ionic liquid and binary mixtures of [C8iQuin][NTf2] with 1-hexanol were measured at atmospheric pressure at three temperatures (298.15, 308.15, and 318.15) K. The surface tension deviations were calculated and correlated by the Redlich–Kister polynomial expansion. The surface thermodynamic functions such as surface entropy and enthalpy were derived from the temperature dependence of the surface tension values. The critical temperature, parachor, and speed of sound for pure ionic liquid were described. A qualitative analysis on these quantities in terms of molecular interactions is reported. The obtained results indicate that ionic liquid interactions with alcohols are strong dependent on the special trend of packing effects and hydrogen bonding of this ionic liquid with hydroxylic solvents. As previously observed, an increase by a 1-alcohol carbon chain length leads to lower interactions on mixing.