The excess molar volume, viscosity deviation and excess Gibbs free energy of activation of viscous flow have been investigated from the density and shear viscosity measurements of water–dioxane mixtures over the entire range of mole fractions from 293.15 to 309.15 K. The results were fitted by the Redlich–Kister equation. Partial molar volume and Gibbs energy at infinite dilution were deduced from four methods, activation parameters and partial molar Gibbs energy of activation of viscous flow against compositions were investigated. The water–dioxane interactions have principally an H-bound character and there are two principal types’ structures limited by 0.08 mole fraction in dioxane. The reduced Redlich–Kister excess properties provide an indication of the intermolecular interactions and for dioxane–water cluster formation as suggested in the literature.

The reduced Redlich–Kister excess molar Gibbs energy of activation of viscous flow and derived properties in 1,4-dioxane + water binary mixtures from 293.15 to 309.15 K

Salt-induced phase separation of 1,4-dioxane (D) + water (W) with KCl has been investigated by measuring the electrical conductivity (κ) and the refractive index (n) along the coexisting curve in the vicinity and far from the lower critical solution temperature (LCST) using a conductometer and a refractometer By visual method, the lower critical temperature (Tc) was determined to be (311032 ± 0015) K with the mole fraction of dioxane on a salt-free basis: x′D = nD/(nD + nW) = 0295 ± 0002 The conductivity and refractive index were carried out in the range of 0010 K < (T − Tc) < 17500 K Critical values were fitted and compared with those predicted by models proposed in the literature The electrical conductivity and refractive index coexistence curve data were analyzed to determine the critical exponent (β) associated with the coexistence curve The results show that those (κ and n) constitute good order parameters as valid as the volume fraction In the neighborhood of the LCST (T/Tc − 1 < 3·10−2)

KCl-Induced Phase Separation of 1,4-Dioxane + Water Mixtures Studied by Electrical Conductivity and Refractive Index †

Density and refractive index measurements of critical mixture 1,4-dioxane + water + saturated KCl in homogenous phase region

The ternary critical mixture of 1,4-dioxane (1) + water (2) + saturated KCl (3) has a lower critical point. The viscosity η and electrical conductivity κ of this system have been measured as function of temperature for nine critical mixtures along the coexistence curve below the temperature of phase transition. The water mole fraction in free basis x′2 in the mixtures extends from (0.550 to 0.880) and the molality m of KCl from (0.47 to 2.039) mol·kg−1. The viscosity was found to decrease with an increase in temperature, water mole fraction, and the molality of KCl, while the electrical conductivity increases with an increase in temperature, with the water mole fraction and molality of salt. The viscosity and electrical conductivity represented anomalies near the critical temperature Tc. The critical electrical conductivity κc varies with water mass fraction w2 as a second degree polynomial and with the molality m of salt as a third degree polynomial. The variation of critical composition in water and in ...

Transport Properties in 1,4-Dioxane + Water + Saturated KCl Critical Mixture by Measuring Viscosity and Electrical Conductivity

Etude spectroscopique des dérivés du peroxyde d'hydrogène—VII Le peroxyhydrate de dioxanne C4H8O2· H2O2

The phase diagrams of the systems sodium chlorate – water – dioxane and lithium chlorate – water – dioxane have been determined at 25 °C.The sodium chlorate – water – dioxane diagram is relatively ...

W. B. Maryk

Papers

The systems sodium chlorate – water – dioxane and lithium chlorate – water – dioxane, at 25°