Excess molar enthalpies for (benzonitrile + an aromatic hydrocarbon) atT = 298.15 K

The excess molar enthalpies of (benzonitrile  +  benzene, or methylbenzene, or 1,2-dimethylbenzene, or 1,3-dimethylbenzene, or 1,4-dimethylbenzene, or 1,3,5-trimethylbenzene, or ethylbenzene) have been determined at T =  298.15 K. The excess molar enthalpies range from  − 10 J · mol ^− 1for methylbenzene to 130 J · mol ^− 1for 1,3,5-trimethylbenzene. The Redlich–Kister equation, the NRTL, and UNIQUAC models were used to correlate the data. The results indicate a relatively strong association between benzonitrile and each of the aromatic compounds, decreasing with increasing methyl substitution on the benzene moiety.     

Excess molar enthalpies and excess molar volumes of (an alkanol + a nitrile compound) atT = 298.15 K andp = 0.1 MPa

Excess molar enthalpies and excess molar volumes at T =  298.15 K andp =  0.1 MPa are reported for (methanol, or ethanol, or 1-propanol  +  1,4-dicyanobutane, or butanenitrile, or benzonitrile). For all the mixtures investigated in this work the excess molar enthalpy is large and positive. The excess molar enthalpy decreases as the carbon chain number of the alkanol species increases from methanol to propanol. The excess molar volumes are both positive and negative. The Extended Real Associated Solution and the Flory–Benson–Treszczanowicz models were used to represent the data. Both these models describe better the excess molar enthalpy than the excess molar volumes of (an alkanol  +  a nitrile compound).     

Excess molar volumes of (an alkane + 1-chloroalkane) atT = 298.15 K

The densities of the following: (pentane  +  1-chloropropane, or 1-chlorobutane, or 1-chloropentane, or 1-chlorohexane), (hexane  +  1-chloropropane, or 1-chlorobutane, or 1-chloropentane, or 1-chlorohexane), (heptane  +  1-chloropropane, or 1-chlorobutane, or 1-chloropentane, or 1-chlorohexane), (octane  +  1-chloropropane, or 1-chlorobutane, or 1-chloropentane, or 1-chlorohexane), were measured at T =  298.15 K by means of a vibrating-tube densimeter. The excess molar volumes V_m^E, calculated from the density data, are negative for (pentane  +  1-chloropentane, or 1-chlorohexane) and (hexane  +  1-chlorohexane) over the entire range of composition. (Pentane  +  1-chlorobutane), (hexane  +  1-chloropentane) and (heptane  +  1-chlorohexane) exhibit an S-shapedV_m^E dependence. For all the other systems,V_m^E is positive. The V_m^Eresults were correlated using the fourth-order Redlich–Kister equation, with the maximum likelihood principle being applied for determining the adjustable parameters.     

The excess molar volumes and enthalpies of (N-methyl-2-pyrrolidinone + an alcohol) atT = 298.15 K and the application of the ERAS theory

Excess molar volumes V_m^EatT =  298.15 K and atmospheric pressure are reported for (N -methyl-2-pyrrolidinone  +  propan-2-ol, or butan-1-ol, or butan-2-ol, or 2-methylpropan-1-ol ). TheV_m^E have been calculated from measured values of density using the vibrating tube technique. The results are discussed in terms of the hydrogen bonding and other intermolecular association. Excess molar enthalpiesH_m^E at T =  298.15 K and atmospheric pressure are reported for (N -methyl-2-pyrrolidinone  +  propan-1-ol, or propan-2-ol, or butan-1-ol, or butan-2-ol, or 2-methylpropan-1-ol). The H_m^Ehave been obtained using flow calorimetry. The experimental results have been correlated and compared with the results from the Extended Real Associated Solution (ERAS) theory. The parameters adjusted to the mixtures properties are two cross association parameters and the interaction parameter responsible for the exchange energy of the van der Waals interactions. Self-association parameters of the alcohols and NMP are taken from the literature.     

Excess molar enthalpies of (acetonitrile + butan-2-one) and (methanol + acetonitrile + butan-2-one) atT = 298.15 K

The excess molar enthalpies of (acetonitrile  +  butan-2-one) and (methanol  +  acetonitrile  +  butan-2-one) were measured atT =  298.15 K and atmospheric pressure using a flow microcalorimeter. The experimental results are correlated with polynomial equations and compared with those calculated from associated solution models taking account into self-association of methanol and acetonitrile as well as solvation between unlike molecules and a non-polar interaction term.     

Excess molar volumes,and excess molar enthalpies of (N-methyl-2-pyrrolidinone + an ether ) at the temperature 298.15 K

Excess molar volumes V_m^E have been calculated from measured density values over the whole composition range at T =  298.15 K and atmospheric pressure for six { N -methyl-2-pyrrolidinone  +  1,1-dimethylethyl methyl ether, or dipropyl ether, or 1,1-dimethylpropyl methyl ether, or diisopropyl ether, or dibutyl ether, or dipentyl ether}. Excess molar enthalpiesH_m^E were also measured for five { N -methyl-2-pyrrolidinone  +  1,1-dimethylethyl methyl ether, or dipropyl ether, or 1,1-dimethylpropyl methyl ether, or diisopropyl ether, or dibutyl ether} at T =  298.15 K and atmospheric pressure. The results are discussed in terms of intermolecular associations. The experimental results have been correlated with the UNIQUAC and NRTL equations.     

The excess molar enthalpies of (N-methyl-2-pyrrolidinone + mono-, or di-, or trichlorobenzene) atT = 298.15 K

Excess molar enthalpies H_m^EatT =  298.15 K are reported for (N -methyl-2-pyrrolidinone  +  chlorobenzene, or 1,2-dichlorobenzene, or 1,3-dichlorobenzene, or 1,2,4,-trichlorobenzene). The values ofH_m^E were obtained by using the flow calorimetric method. All the mixtures, over the whole composition range, are formed exothermically. The H_m^Eresults are discussed in terms of the NRTL and UNIQUAC models.     

Excess molar volumes and excess molar enthalpies of binary mixtures for 1,2-dichloropropane + 2-alkoxyethanol acetates at 298.15 K

The excess molar volumes and excess molar enthalpies over the whole range of composition have been measured for the binary mixtures formed by 1,2-dichloropropane (1,2-DCP) with three 2-alkoxyethanol acetates at 298.15 K and atmospheric pressure using a digital vibrating-tube densimeter and an isothermal calorimeter with flow-mixing cell, respectively. The 2-alkoxyethanol acetates are ethylene glycol monomethyl ether acetate (EGMEA), ethylene glycol monoethyl ether acetate (EGEEA), and ethylene glycol monobutyl ether acetate (EGBEA). The of the mixture has been shown positive for EGMEA, ‘S-shaped’ for EGEEA, being negative at low and positive at high mole fraction of 1,2-DCP, and negative for EGBEA. All the values for the above mixtures showed an exothermic effect (negative values) which increase with increase in carbon number of the 2-alkoxyethanol acetates, showing minimum values varying from −374 J mol⁻¹ (EGMEA) to −428 J mol⁻¹ (EGBEA) around 0.54–0.56 mol fraction of 1,2-DCP. The experimental results of and were fitted to Redlich–Kister equation to correlate the composition dependence of both excess properties. In this work, the experimental excess enthalpy data have been also correlated using thermodynamic models (Wilson, NRTL, and UNIQUAC) and have been qualitatively discussed.     

Excess molar volume of (linalool + an alkanol) atT = 303.15 K

In this paper, densities of (linalool  +  methanol, or ethanol, or n -propanol, or n -butanol) are determined at T =  303.15 K using a vibrating-tube densimeter. The excess molar volumes V_m^Evalues are negative in all the systems over the entire composition range and correlated by the Redlich–Kister equation. The effects of chain length of alkanols onV_m^E have been discussed.     

Excess molar volumes and partial molar volumes for (propionitrile + an alkanol) at T = 298.15 K and p = 0.1 MPa

The excess molar volumes and the partial molar volumes for (propionitrile + an alkanol) at T = 298.15 K and at atmospheric pressure are reported. The hydrogen bonding between the OH⋯NC groups are discussed in terms of the chain length of the alkanol. The alkanols studied are (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 1-pentanol).The excess molar volume data was fitted to the Redlich–Kister equation The partial molar volumes were calculated from the Redlich–Kister coefficients.     

Excess molar enthalpies and excess molar heat capacities of (2-butanone + cyclohexane,or methylcyclohexane,or benzene,or toluene,or chlorobenzene,or cyclohexanone) atT = 298.15 K

Excess molar enthalpies of (2- butanone  +  cyclohexane, or methylcyclohexane, or toluene, or chlorobenzene, or cyclohexanone) and excess molar heat capacities of (2- butanone  +  benzene, or toluene, or chlorobenzene, or cyclohexanone) were measured atT =  298.15 K. Aliphatic systems were endothermic and the chlorobenzene system was exothermic. On the other hand, the toluene system changed sign to be S-shaped similar to the benzene system reported by Kiyohara et al. The values of excess molar enthalpies of the present mixtures were slightly larger than the corresponding mixtures of cyclohexanone already reported. Excess molar heat capacities of aromatic systems were characteristically S-shaped for the mixture containing aromatics. The values of the present mixtures were less than the corresponding mixtures of cyclohexanone. The mixture (2-butanone  +  cyclohexanone) was endothermic forH_m^E and negative for C_p,m^E.     

The excess molar enthalpies and volumes of (N-methyl-2-pyrrolidinone + an alkan-1-ol) at T=298.15 K

The excess molar enthalpies H_m^E, for the mixtures (N-methyl-2-pyrrolidinone + ethanol, or pentan-1-ol, or hexan-1-ol, or heptan-1-ol, or octan-1-ol, or nonal-1-ol, or decan-1-ol, or undecan-1-ol) at T=298.15 K and atmospheric pressure have been obtained using flow calorimetry. Excess molar volumes at T=298.15 K and atmospheric pressure have also been determined for (N-methyl-2-pyrrolidinone + nonal-1-ol, or decan-1-ol, or undecan-1-ol) from density measurements using a vibrating tube densimeter. The experimental results have been correlated and compared with the results from the Flory–Benson–Treszczanowicz (FBT) theory and from the Extended Real Associated Solution (ERAS) model. The ERAS model accounts free volume effects according to the Flory–Patterson model and additionally association effects between the molecules involved. For the mixtures studied here the association effects arise from the self association of an alkan-1-ol molecules and also the cross-association of the proton of the alkan-1-ol with carbonyl oxygen of N-methyl-2-pyrrolidinone (NMP) molecule. The parameters adjusted to the mixtures properties are two cross-association parameters and the interaction parameter responsible for the exchange energy of the van der Waals interactions. Self-association parameters of the alcohols and NMP are taken from the literature.     

Excess enthalpies for mixtures of acrylonitrile and an aromatic hydrocarbon at T = 298.15 K and p = 101325 Pa

Excess molar enthalpies for (acrylonitrile  +  benzene, or methylbenzene, or 1,2-dimethylbenzene, or 1,3-dimethylbenzene, or 1,4-dimethylbenzene, or 1,3,5-trimethylbenzene, or ethylbenzene) atT =  298.15 K and p =  101325 Pa are presented. The excess molar enthalpy range from 531J · mol ^− 1at x =  0.5 for 1,3,5-trimethylbenzene to 210J · mol ^− 1at x =  0.5 for toluene. The Redlich–Kister equation, the NRTL and UNIQUAC models were used to correlate the data.     

Densities,refractive indices,and derived properties of (cyclohexane,orn-heptane + an aromatic hydrocarbon) atT = 298.15 K

This paper reports experimental densities and refractive indices of (cyclohexane, or n -heptane  + o -xylene, or m -xylene, or p -xylene, or ethylbenzene) over the whole composition range at T =  298.15 K and at atmospheric pressure. Excess molar volumes and changes of refractive indices were calculated from the experimental data obtained. Partial excess molar volumes were also computed for all the mixtures studied. The results were fitted by means of the Redlich–Kister equation with the aid of F -test to optimize the number of parameters. Measurements were compared with other literature values. Different empirical and semiempirical models were applied in order to estimate physical property values and good agreement was obtained with experimental results.     

Excess enthalpies and excess heat capacities of binary mixtures of (cyclohexanone,or 2-butanone,or 1,4-dioxane + 1,2-dimethoxyethane) and (1,4-dioxane + 1,2-dimethoxyethane) atT = 298.15 K

Excess enthalpies and excess heat capacities of { x 2-butanone  +  (1  − x)1,4-dioxane}, and { x cyclohexanone, or 2-butanone, or 1,4-dioxane  +  (1  − x)1,2-dimethoxyethane} were measured atT =  298.15 K. Excess enthalpies were negative for { x 2-butanone  +  (1  − x)1,2-dimethoxyethane}, and negative with a small positive part in the region ofx >  0.8 for { x cyclohexanone  +  (1  − x)1,2-dimethoxyethane}, whereas excess enthalpies of { x 2-butanone  +  (1  − x)1,4-dioxane} were positive as for { x cyclohexanone  +  (1  − x)1,4-dioxane} previously reported. Excess enthalpies of {x 1,4-dioxane  +  (1  − x)1,2-dimethoxyethane} were positive. The results were compared with the systems reported earlier. Excess heat capacities are positive for { x 2-butanone  +  (1  − x)1,2-dimethoxyethane} and { x cyclohexanone  +  (1  − x)1,2-dimethoxyethane}, and negative for { x 2-butanone  +  (1  − x)1,4-dioxane} and { x 1,4-dioxane  +  (1  − x)1,2-dimethoxyethane}. The last mixture shows a W-shaped curve of excess heat capacity.     

Volumetric properties of (an organic compound + di-n-butyl ether) atT = 298.15 K

Excess molar volumes V_m^Eof {di- n -butyl ether (DBE)  +  a monofunctional organic compound} have been determined atT =  298.15 K over the whole composition range by means of a vibrating-tube densimeter. TheV_m^E values were either positive (propylamine, or butylamine, or acetone, or tetrahydrofuran  +  DBE) or negative (methanol, or butanol, or diethyl ether, or cyclopentanone, or acetonitrile  +  DBE). Markedly asymmetric V_m^Ecurves were displayed by (DBE  +  methanol) and (DBE  +  acetonitrile). Partial molar volumes __ V_m^oat infinite dilution in DBE, both from this work and the literature, were analysed in terms of an additivity scheme, and the group contributions thus obtained were discussed and compared with analogous results in water. DBE revealed a greater capability of distinguishing between polar and non-polar solutes, as well as in discriminating differently shaped molecules (unbranched, branched, cyclic). The limiting slopes of apparent excess molar volumes are evaluated and briefly discussed in terms of solute–solute and solute–solvent interactions.     

Thermodynamic excess properties for binary mixtures of (butanenitrile + a carboxylic acid) atT = 298.15 K

Excess molar enthalpies and excess molar volumes for (butanenitrile  +  acetic acid, or propanoic acid, or butanoic acid, or 2-methylpropanoic acid, or pentanoic acid, or 3-me thylbutanoic acid) atT =  298.15 K are presented. The excess molar enthalpy values are found to be positive for all six systems, whereas the excess molar volumes are found to be negative. The excess molar enthalpy values are correlated by the UNIQUAC and NRTL models and also by the Redlich–Kister polynomial.     

(Liquid + liquid) equilibria of (heptane,or hexane,or cyclohexane + toluene + 1,3-dimethyl-2-imidazolidinone) ternary systems at T = 298.15 K

Experimental (liquid + liquid) equilibrium data for the mixtures of (heptane, or hexane, or cyclohexane + toluene + 1,3-dimethyl-2-imidazolidinone) were determined at T = 298.15 K and P = 101.3 kPa. The solubility (binodal) curves and tie-line end compositions are reported for the related mixtures and presented as complete phase diagrams. Distribution coefficients and separation factors were evaluated for the immiscibility region. The reliability of the experimental tie-line results was verified by using the Othmer–Tobias correlation. The experimental tie-line data were correlated by UNIQUAC model, which gave satisfactory representation for the systems. It was observed that the separation of toluene from cyclohexane is easier to achieve than from heptane and hexane.