Teresa Treszczanowicz

Review of experimental and recommended data for the excess molar volumes of 1-alkanol + n-alkane binary mixtures

A review of excess volume data for (1-alkanol + n-alkane) systems and recommended data sets are presented. The review covers 54 systems in 207 data sets published up to 1991. The experimental data are represented in a reduced form as parameters of the best smoothing equation together with the standard and maximum deviations. For all data the temperature, pressure, number of data points, and method of measurement are given. Six recommended data sets are selected from the collected systems: methanol + n-heptane, ethanol + n-hexane, ethanol + n-heptane, 1-propanol + n-heptane, 1-butanol + n-heptane and 1-hexanol + n-hexane. Recommendation are also given for the five key systems of the IUPAC Project.

Application of the flory and sanchez-lacombe theories to the excess enthalpy and excess volume of ether + hydrocarbon systems

Abstract Excess volume measurements for 2,5-dioxahexane + heptane and + octane, for 3,5-dioxaheptane + heptane and for isopropyl ether + heptane at 298.15 K are reported. The changes in excess volume observed in this work and described in the literature, as well as the reported excess enthalpy data for chain aliphatic ether+alkane systems as a function of composition are discussed in terms of the new Flory and the Sanchez-Lacombe theories. The interaction parameters for this class of mixtures have been correlated with the oxygen-atom surface fraction in the ether molecule.

Isothermal vapour-liquid equilibria for 11 examples of (an ether+a hydrocarbon)

Abstract A recirculating still was used in the determination of isothermal vapour-liquid equilibria for eight examples of (an aliphatic ether + an alkane) and three of (an aliphatic ether + benzene) at a total of 14 isothermal conditions. Activity coefficients and excess molar Gibbs free energies were evaluated and then correlated.

Prediction of the excess volume and isobaric thermal expansion for 1-alkanol + n-alkane systems in terms of an association model with a Flory contribution term

The predictive ability of the model proposed by Treszczanowicz and Benson [A.J. Treszczanowicz, G.C. Benson, Fluid Phase Equilib. 23 (1985) 117] is tested for all available excess volume VE and excess thermal expansion ApE = (∂VE∂T)p data for 1-alkanol + alkane mixtures. The model takes into consideration the chemical effect of H-bond disruption described by an athermal-associated mixture model and the free-volume effect described by a Flory equation of state contribution. The model predicts VE and ApE well for mixtures formed by alkanols from ethanol to 1-dodecanol and n-alkanes from n-pentane to n-hexadecane. In particular, the model predicts an intersection point for series S-shaped VE and ApE isotherms. This phenomenon is discussed as resulting from a balance between the positive (association, non-specific interactions) and negative (free-volume) contributions.

Temperature dependence of excess volume of 1-alkanol + n-alkane binary systems in terms of an association model with a Flory contribution term

Abstract The model of associated mixtures proposed recently (A.T. Treszczanowicz and G.C. Benson, Fluid Phase Equilibria, 23 (1985) 117), for the excess volume is used to predict its temperature derivative A E p = (∂ V E /∂ T ) p for 1-alkanol + alkane mixtures. The model parameters estimated for excess volume are adopted. The model predicts the A E p values fairly well. The shape and size of A E p are discussed as a result of mutual compensation effects of association, non-specific interactions and free volume contributions.

Excess Molar Volumes for Binary Mixtures of 1-Alkanol and 1-Alkene. III. The System 1-Hexanol + 1-Alkene at 25°C

Excess molar volumes, VE, are reported for binary mixtures of 1-hexanol with the homologous C6, C7, C8, and C10 1-alkenes at 25°C. In this series of mixtures, the VE values vary as a function of mole fraction from positive–negative “sigmoid” shaped curves exhibiting a very small positive lobe in the dilute alkanol region for the shortest chain 1-alkene to positive values over the whole concentration range for the longer chain 1-alkene. The partial molar excess volumes, ViE, were calculated for the components over the whole concentration range. The partial molar volume of 1-hexanol in the 1-hexene system shows a large and sharp minimum and in the 1-decene system is positive over the whole concentration range. The modified model [Treszczanowicz et al., J. Solution Chem.31, 455 (2002) originally proposed by Treszczanowicz and Benson Fluid Phase Equilibr.23, 117 (1985)] was used for the interpretation and prediction of the reported data. The model describes qualitatively the variation of VE with the length of the molecule and concentration as a result of superposition of the contributions of association, free volume, and nonspecific interactions.

(Vapour + liquid) equilibria of (3,6-dioxaoctane + n-heptane) at 343.15 K

Abstract Isothermal (vapour + liquid) equilibrium values for (3,6-dioxaoctane + n -heptane) were determined at 343.15 K using a recirculating still. Activity coefficients and excess molar Gibbs free energies were calculated and then correlated. The still was also used to determine the vapour pressure of 3,6-dioxaoctane at 339.18 to 382.80 K.

Excess isobaric thermal expansion in the systems formed by oligooxaethylene and alkane in terms of an associated mixture model with equation of state contribution

Abstract The concept of self-association oligooxaethylenes (glymes) is discussed in terms of the associated mixture model with equation of state contributions [A.J. Treszczanowicz, G.C. Benson, Fluid Phase Equilib., 23 (1985) 117]. The model was applied to interpret and describe the excess thermodynamic properties of binary mixtures formed by 2,5-dioxahexane or 2,5,8-trioxanonane with n -alkane. The excesses enthalpy H E , heat capacity C p E , volume V E and isobaric thermal expansion A p E =(∂ V E /∂ T ) p were used to estimate the model parameters: standard enthalpy, entropy and volume of self-association and non-specific interactions parameter. The application of the equation of state alone does not allow to describe A p E and other thermodynamic properties, unless association is taken into consideration. Calculations show the glymes to be very weakly self-associated, and characterized by the high monomer concentration in the pure state. The description of the glyme+alkane mixtures was compared with the results for relatively strong self-associated 1-alkanol mixtures. The chemical contributions to A p E and C p E for glyme mixtures have negative signs, different than those for alkanol mixtures. The association, even if it is weak, has an essential contribution to the thermodynamic properties.

Prediction of the temperature dependence of excess volumes in dilute solutions of 1-alkanol in n-alkane

A model consisting of the association and Florys equation of state contributions (Treszczanowicz and Benson, 1985) is used to predict the temperature dependence of the excess volume AEP = (∂VE∂T)P in diluted regions of alkanols. The model predicts a complex shape for the AEP dependence for dilute alkanol solutions as a result of the balance between the association and free volume contributions.

Prediction of temperature dependence of the excess volume: (∂VE/∂T)p and (∂2VE/∂T2)p for 1-alkanol + an alkane binary systems in terms of an associated mixture model

Abstract The predictive ability of the model proposed by Treszczanowicz and Benson [Fluid Phase Equilib. 23 (1985) 117] is tested for temperature dependence of the excess volume: excess molar isobaric thermal expansion defined as A p E =( ∂V E / ∂T ) p and ( ∂ 2 V E / ∂T 2 ) p for binary systems formed by an 1-alkanol (from C 2 to C 12 ) and an alkane (from C 4 to C 14 ) for all available literature data. The model equations for these properties are expressed as sums of the three contributions: self-association described by athermal associated mixture model and free volume and non-specific interactions described by Flory equation of state. The model correctly predicts A p E and sign of temperature derivative ( ∂ 2 V E / ∂T 2 ) p for regarded class of mixtures. Moreover, the model predicts complex shape of the A p E curve and its temperature changes for diluted 1-decanol in n -hexane solutions.