scholarly journals Vapor pressure, density, viscosity and refractive index of dimethyl sulfoxide + 1,4-dimethylbenzene system

2008 ◽  
Vol 73 (1) ◽  
pp. 73-85 ◽  
Author(s):  
Oana Ciocirlan ◽  
Olga Iulian

This paper reports the experimental results of isothermal vapor-liquid equilibrium data between 303.15 and 333.15 K, and densities, viscosities, refractive indices from 298.15 to 323.15 K of the dimethyl sulfoxide + 1,4-dime?thylbenzene system over the entire range of mixture composition. The obtained PTX data were correlated by the Wilson and NRTL models and estimated by the UNIFAC model. The excess Gibbs energy and activity coefficients were calculated and compared with others excess properties. Excess molar volumes, viscosity deviations and deviations in refractivity were calculated from the experimental data; all the computed quantities were fitted to the Redlich-Kister equation. The resulting excess functions were interpreted in terms of structure and interactions.

2009 ◽  
Vol 74 (3) ◽  
pp. 317-329 ◽  
Author(s):  
Oana Ciocirlan ◽  
Olga Iulian

This work reports the experimental results of the densities, viscosities and refractive indices between 298.15 and 323.15 K of the dimethyl sulfoxide + o-xylene system over the entire composition range of the mixtures. The excess molar volumes (VE), viscosity deviations (?v), excess Gibbs energy of activation of viscous flow (G*E) and deviations in the refraction (?R) were calculated from the experimental data; all the computed quantities were fitted to the Redlich-Kister equation. The system exhibits moderate negative values for the investigated excess properties. The resulting excess functions were interpreted in structural and interactional terms. From the experimental data, the thermodynamic functions of the activation of viscous flow were estimated. The viscosity data were correlated with several semi-empirical equations. The two-parameter McAllister equation can give very good results.


2019 ◽  
Vol 31 (4) ◽  
pp. 820-824
Author(s):  
Husam S. Khalaf ◽  
Zainab A.H. Al-Dulaimy ◽  
Ahmed M. Abbas ◽  
Maida H. Saleem

At the temperature 298.15 K, some physical properties such as: refractive indices (nD), viscosities (η) and densities (ρ) were studied in four liquid-liquid mixtures: carboxylic acids (HCOOH, CH3COOH, CH3CH2COOH and CH3CH2CH2COOH) with tetrahydrofurfuryl alcohol (THFA) with the identified configuration set. These empirical data were utilized to estimate the excess molar volumes (Vm E), refractive index perversions (ΔR), viscosity deviations (ηE) and excess molar Gibbs free energy (ΔG*E). Values of Vm E, ηE , ΔG*E and ΔR were plotted versus mole fraction of tetrahydrofurfuryl alcohol. In all cases, the values of Vm E, ηE , ΔG*E and ΔR that obtained in this study were found to be negative at 298.15 K. The excess parameters were applied in the Redlich-Kister equation by utilizing multi-parameter coefficients that concluded binary coefficients and in respect to the standard deviation. The difference of these characteristics with the formation of binary liquid systems indicates the absence of bipolar bond, variation in the shape and size of component molecules, hydrogen bonding and dipolar interaction among unlike molecules.


2000 ◽  
Vol 78 (8) ◽  
pp. 1121-1127 ◽  
Author(s):  
Alberto G Camacho ◽  
Miguel A Postigo ◽  
Graciela C Pedrosa ◽  
Inés L Acevedo ◽  
Miguel Katz

Excess molar volumes and excess refractive indices of the n-octanol + 1,4-dioxane + 2-butanol system and the three corresponding binary mixtures have been determined at 298.15 K by measuring densities and refractive indices. Different expressions exist in the literature to predict these excess properties from binary data. An estimation of excess molar volumes is also evaluated using a modified Heller equation which depends on the refractive indices of the mixtures. A comparison of the predictions of different methods with the experimental values of the physical properties has been made.Key words: excess molar volumes, densities, refractive indices, n-octanol, 1,4-dioxane, 2-butanol, ternary system.


Author(s):  
Adrian Buep

Abstract Intermolecular associations in liquid systems of non-polar and slightly polar compounds were studied through excess molar volumes (VME), and excess dielectric properties (εE and nD2E) for mixtures of carbon tetrachloride (CCl4) with benzene (C6H6), toluene (C6H5CH3), and p-xylene (p−(CH3)2C6H4). These excess properties were calculated from measurements of density (ρ), static permittivity (ε), and refractive index (nD) over the whole range of concentrations, at 298.15 K. The values of the excess dielectric properties for these mixtures were fitted in two different ways, one through least squares using the Redlich–Kister equation and the other using a model developed to explain deviations from ideality. The first fit was found to be descriptive while the second gave the equilibrium constant values for the interaction products actually formed in the mixtures and the respective electronic polarizabilities and dipole moments, indicating the existence of interaction products.


1983 ◽  
Vol 48 (10) ◽  
pp. 2879-2887 ◽  
Author(s):  
Jan Linek

Isothermal vapour-liquid equilibrium data at 65, 73 and 80 °C and isobaric ones at 101.3 kPa were measured in the tetrachloromethane-n-butyl alcohol system. A modified circulation still of the Gilespie type was used for the measurements. Under the conditions of measurements, the system exhibits positive deviations from Raoult's law and minimum boiling-point azeotropes. The experimental data were fitted to a number of correlation equations. The best correlation was reached with the Wilson equation but the regression failed in some cases. Therefore the results for the 5th order Redlich-Kister equation are presented.


Sign in / Sign up

Export Citation Format

Share Document