• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.663-670
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• 2009

Performing random number simulations, we obtained an approximate distribution of the number of ways arranging molecules in a binary lattice solution of nonrandom mixing with a specific interaction. From the distribution an approximate equation of excess Gibbs energy for a binary lattice solution was derived. Using the equation, liquid-vapor equilibrium at constant pressure for 15 binary solutions were calculated and compared with the result from Wilson equation, Van Laar equation and Redlich-Kister equation.

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1165-1170
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• 2004

The applicability of the combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation for correlation of various solvatochromic parameters (SP) with composition is shown employing 84 experimental data sets for aqueous and organic binary solvent systems at temperatures ranging 15 to $75^{\circ}C$. The model provides a simple computational model to correlate/predict different SP values in various binary solvent systems. In proposed equations, $MPD_s$ (mean percentage deviations) are between 0.0500% and 6.9591% in mixtures of dimethyl sulfoxide with 2-methylpropan-2-ol and benzene with 2-methylpropan-2-ol, respectively. Correlation of the calculated and experimental values of various SP give an equation with an overall mean percentage deviation (OMPD) of 1.1900, $R^2$ = 0.99692, s.e = 0.01223 and F = 341925.51. Approximately 70% of the calculated SP values have IPD (individual percentage deviation) lower than one and it is possible to predict unmeasured SP values by using only eight experimental data.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.373-378
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• 2011

The present paper reports the study of binary mixtures and their properties over the entire range of composition at temperatures 288, 298, 308 and 318 K. Excess dielectric constant, excess molar volume, excess refractive index, molar refraction and excess molar refraction at different temperatures have been computed from the experimentally measured values of the aforesaid parameters and fitted to the Redlich-Kister equation. Excess dielectric constant, excess molar volume excess molar polarizations are negative whereas excess refractive indices are positive over entire mole fraction of methyl acetate for all temperatures. The results are discussed in light of intermolecular interactions occurring in the binary mixture. Estimated coefficients of the Redlich-Kister polynomials and the standard error along the coefficients are also reported.

• Journal of the Korean Society of Industry Convergence
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• v.14 no.1
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• pp.9-14
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• 2011

The excess molar enthalpies $H_m^E$ at T=298.15 K and p=101.3 kPa of ternary system {1,2-dichloropropane (1,2-DCP) + 1,3-dioxolane+ 1,4-dioxane} were predicted by using the binary contribution model of $Radojkovi{\check{c}}$ with correlated sub-binary Redlich-Kister parameters. Excess partial molar enthalpies ${\bar{H}}_i^E$ were also calculated for the binary systems {1,2-dichloropropane + 1,3-dioxolane}, {1,2-dichloropropane + 1,4-dioxane} and {1,3-dioxolane + 1,4-dioxane} using adjustable parameters of Redlich-Kister equation. By extrapolation of excess partial molar enthalpies to infinite dilution, limiting excess partial molar enthalpies ${\bar{H}}_i^{E,{\infty}}$ of each component were also obtained. The ternary excess molar enthalpies excess partial molar enthalpies of these sub-binary systems have been calculated by using our previously reported results.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.706-713
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• 1994

Isothermal vapor-Liquid equilibrium data have been measured for binary systems MTBE-methanol, MTBE-n-heptane, and methanol-n-heptane at $45^{\circ}C$ and $65^{\circ}C$ by using head space gas chromato-graphy (H.S.G.C). Among these systems a minimum azeotrope was observed in both of MTBE-methanol system and n-heptane-methanol system. Particularly n-heptane-methanol system has a heterogeneous minimum azotrope since it has an immisible region. These equilibrium data were correlated with the excess Gibbs energy model, and the thermodynamic consistency test was also carried out by using Redlich-Kister equation.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.444-452
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• 2006

This paper reports experimental excess molar volumes $V^E_m$ using a digital vibrating-tube densimeter and excess molar enthalpies $H^E_m$ by means of an isothermal microcalorimeter with a flow mixing cell for the binary mixtures{1,2-dichloropropane + 2-(2-methoxyethoxy)ethanol} and {1,2-dichloropropane + 2-(2-ethoxyethoxy)ethanol} at 298.15 K under atmospheric pressure. All the $V^E_m$ and $H^E_m$ of the two binary mixtures showed S-shaped forms, being negative for poor and positive for rich 1,2-dichloropropane mole fractions. These show that the excess properties were shown to be negative deviation from ideality due to the strong self-association effect among 2-(2-alkoxyethoxy)ethanol molecules at an early stage of mixing, a relatively high energy then is needed to break hydrogen bonds of 2-(2-alkoxyethoxy)ethanol with an increase ofhalogenated hydrocarbon molecular at high mole fraction of 1,2-dichloropropane. The values of excess molar properties($V^E_m$ and $H^E_m$) were fitted by the Redlich-Kister equation using Nelder-Mead's simplex pattern search method. The Wilson, NRTL, and UNIQUAC models were used to correlate the $H^E_m$ values.

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.295-300
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• 2010

A binary system of 1-propanol and bromochloromethane which exhibits an azeotropic point and a considerable nonideal phase behavior probably due to the large boiling point difference is not amenable in the actual chemical processes such as the distillation tower and absorber. Therefore, experimental data of phase behavior data of this mixture are indispensable in understanding the inherent thermodynamic characteristics for an efficient application of the system in the industrial processes. In this work, the isobaric vapor-liquid equilibrium of a binary mixture consisting of 1-propanol and bromochloromethane was measured by using a recirculating equilibrium cell at various pressures ranging from 30 to 70 kPa. The measured VLE data were correlated in a satisfactory manner by using the UNIQUAC and NRTL models along with the thermodynamic consistency test based on Gibbs/Duhem equation. In addition, the excess molar volume of the mixture was also measured by using a vibrating densitometer and correlated with a Redlich-Kister polynomial.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.20-27
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• 2012

Complex permittivity spectra of Allyl Chloride (AC), 2-Butanone (2-BU) and their binary mixtures over the entire range of concentration were obtained using the Time Domain Reflectometry (TDR) technique in microwave frequency range at various temperatures. Static dielectric constant and relaxation time are obtained from complex permittivity spectra. Density ($\rho$) and refractive index ($n_D$) are also measured. These parameters are used to determine excess dielectric constant, excess inverse relaxation time, excess molar volume, excess molar refraction, polarity, Bruggeman factor and thermodynamic parameters viz. enthalpy of activation and entropy of activation. The values of static dielectric constant and relaxation time increases while density and refractive index decreases with the percentage of 2-Butanone in Allyl Chloride increases. Excess parameters were fitted to a Redlich-Kister equation.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.644-651
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• 2021

Alkyl amines are widely used in various industries. Nowadays these are also used in CO₂ capture technology because amines react with CO₂ and remove it from the flue gas. To make the amines more compatible towards this technology, physico chemical properties may be altered by mixing with other solvents. In the present report, we measured the refractive properties of pure diisopropylamine (DIPA) (1) + isomeric butanol (2) at 298.15 K to 308.15 K. The 𝚫n values were positive for DIPA + n-butanol or sec-butanol or isobutanol or tert-butanol mixtures. The measured data was correlated with Redlich-Kister equation. The excess molar volume data were predicted from refractive index data using Nakata and Sakurai model. The experimental data were also predicted by various correlations, and the prediction capability of these correlations was reported through standard deviation. Further, the deviation in refractive index (𝚫n) data was interpreted by the consideration of specific molecular interactions between DIPA and isomeric butanol.

• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.56-61
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• 2011

Alkyl vinyl ethers such as methyl vinyl ether, propyl vinyl ether, isopropyl vinyl ether, butyl vinyl ether and isobutyl vinyl ether are usually used as industrial solvents and chemical intermediates in the chemical or pharmaceutical industry. Recently, they are popularly used as raw materials for polymer electrolyte membrane fuel cells and as cellulose dyeing assistants. However, very few investigations about process design and operation data were reported for alkyl vinyl ether compounds and there are no data for propyl vinyl ether(PVE) systems as far as we know. In this work, the isothermal VLE data are reported at 333.15 K for the ternary systems of {PVE + ethanol + benzene} by using headspace gas chromatography(HSGC) and these VLE data were correlated using Wilson, NRTL and UNIQUAC equations. The excess volumes($V^E$) and deviations in molar refractivity(${\Delta}R$) data are also reported for the sub binary systems {PVE + ethanol}, {ethanol + benzene} and {PVE + benzene} at 303.15 K. These data were correlated with Redlich-Kister equation. In addition, isoclines of $V^E$ and DR for ternary system {PVE + ethanol + benzene} were also calculated from Radojkovi equation.