Comparison Study on Temperature Dependence of the Interfacial Tension of n-Alkane–Water and n-Alcohol–Water Two Binary Systems

Abstract

A pendant drop shape technique, enhanced by video-image digitization, was applied to measure the interfacial tension for n-alkane− water and n-alcohol−water of 6−9 carbon atoms binary systems at the temperature of 293.2 to 343.2 K. The experimental results of interfacial tension measured by this method were correlated for each binary system as a function of temperature. For n-alkane−water binary system, it could be seen from the results that the interfacial tension decreases with increasing temperature. Further, for each n-alkane−water binary system investigated, all data points determined in the present investigation fall approximately on a straight line, that is, the temperature coefficients of the interfacial tension are uniformly negative. For n-alcohol−water binary system, results demonstrate that all γ−T curves present parabolic profiles, that is, the interfacial tension first increases with increasing temperature, then goes through a maximum and eventually decreases with increasing temperature. Moreover, the temperature at which the maximum of the interfacial tension occurs also increases with the number of carbon atoms in the alcoholic molecular chain. The agreement between the values by this method and those from the literature is fairly good.

Initial Interfacial Tension for Various Organic–Water Systems and Study of the Effect of Solute Concentration and Temperature

“…As methylcyclohexane has only negligible solubility with water, the initial interfacial tension measured in this work may be regarded as the interfacial tension between the mutually saturated phases and should be a part of the interfacial tension database. For the case of cyclohexanol, it is important to mention that cyclohexanol has melting point of 299.08 K; therefore, the interfacial tension value of 3.92 mN/m at 289.35 K is doubtful, though mutual saturation with water may lead to the possibility and should be checked. Interfacial tension of diethyl ether–water may also need to be confirmed.…”

Application of PC-SAFT and DGT for the Prediction of Self-Assembly

“…The modification of the interfacial contribution consists of the use of the interfacial tension, γ LLE , obtained by combining PC-SAFT with the DGT, rather than using the empirical correlations based on the surface tensions, γ VLE , of pure water and pure n -alkanes, as done in the original model. ,, The interfacial tension of n -alkane + water mixtures, γ LLE , can be measured using the drop-volume technique, the pendant-drop method, − or the ring method . A careful analysis of the available experimental data − reveals that the interfacial tensions obtained by Goebel and Lunkenheimer are always higher than the data obtained by all other authors. − Evidently, the pendant-drop method is more suitable for measuring the interfacial tension. The data obtained by Zeppieri et al are close to the data obtained by Tian et al, whereas the data obtained by Aveyard and Haydon or by Mori et al as well as by Matsubara show a remarkable scattering.…”

“…Figure compares experimental data , for water + n -hexane (a) and water + n -decane (b) with interfacial tensions calculated by DGT+PC-SAFT and calculated using the empirical correlation suggested by Nagarajan and Ruckenstein, , which was applied in the original model to calculate Δμ g ,shape,Int 0 / k B T (eq ). It becomes obvious that the empirical correlation applied always results in a linear temperature dependence, whereas the experimental data and the calculations using PC-SAFT and DGT do not follow a linear trend.…”

Liquid‐Liquid Equilibrium and Interfacial Properties of the System Water + Hexylacetate + 1‐Hexanol

“…For the system under study only binary data belonging to the binary subsystems were measured , , . LLE data for the binary subsystems water + 1‐hexanol , , as well as for the binary subsystem water + hexylacetate , are available, this holds true also for interfacial tension data regarding the subsystems water + 1‐hexanol , , , and water + hexylacetate . Considering the ternary system water + 1‐hexanol + hexylacetate no experimental data, to the best of our knowledge, exists in open literature, regarding the LLE, as well as interfacial tension data at T = 298.15 K. Therefore, some experimental data with respect to the LLE and with respect to the interfacial tension were produced in order to verify or falsify the predictions.…”

“…For this propose a similar mixture is chosen, where the middle‐polar component 1‐butanol is replaced by 1‐hexanol having a lower polarity and to the same time the non‐polar component benzene is replaced by hexylacetate having a slightly higher polarity. For the system under study only binary data belonging to the binary subsystems were measured , , . LLE data for the binary subsystems water + 1‐hexanol , , as well as for the binary subsystem water + hexylacetate , are available, this holds true also for interfacial tension data regarding the subsystems water + 1‐hexanol , , , and water + hexylacetate .…”