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Volumetric properties of 1,2-propanediol + ethanol mixtures at different temperatures

2006; Taylor & Francis; Volume: 44; Issue: 5 Linguagem: Inglês

10.1080/00319100600644169

1029-0451

Jackson Jiménez, Fleming Martínez,

Chemical Thermodynamics and Molecular Structure

The excess molar volumes and partial molar volumes of components have been investigated from density measurements in the entire range of mole fractions for the 1,2-propanediol + ethanol system at 20.00, 25.00, 30.00, 35.00 and 40.00°C. The results of excess molar volumes were fitted by Redlich–Kister equation using third-degree polynomials and compared with those available in the literature for other systems. The system exhibited negative excess volumes (up to 0.39 cm3 mol−1 at 25.00°C) due to increased interactions like hydrogen bonding between unlike molecules or large differences in the molar volumes of pure components. The effect of temperature on the different volumetric properties studied has also been analyzed. Finally, the thermal volume expansion coefficient has also been calculated, finding values varying from 0.00073 K−1 for 1,2-propanediol up to 0.00112 K−1 for ethanol at 25.00°C.