SPEEDS OF SOUND, ISENTROPIC COMPRESSIBILITIES AND EXCESS MOLAR VOLUMES OF MIXTURES OF 1-ALKANOL + DIBUTYL ETHER AT 293.15, 298.15 AND 303.15 K
Advancing the chemical engineering fundamentals
Thermodynamics (T2-1P)
Keywords: densities, compressibility, 1-alkanol, dibutyl ether
Studies on excess functions of binary liquid mixtures have been performed to understand the molecular interactions between the solution components, as well as for engineering applications. As continuation of our previous works on thermodynamic properties of binary systems containing 1-alkanols which present intermolecular self-association due to the presence of –O- and –OH groups in the same molecule with organic solvents, we present here the density and speed of sound measurements for 1-butanol, 1-pentanol and 1-hexanol + dibutyl ether systems. The measurements were carried out at atmospheric pressure at 293.15, 298.15 and 303.15 K. All quantities have been determined over the whole mole fraction range. The data were used to calculate excess molar volumes, isentropic compressibilities and the thermal expansion coefficients.
The excess molar volumes are negative over the whole mole-fraction range and slightly asymmetrical. The minimum is skewed towards the region of high mole fraction of dibutyl ether as the 1-alkanol chain is increased. For the same value of mole fraction, the excess molar volume hardly changes with the temperature and decreases as the alkyl chain length of 1-alkanol increases. The increment of the isentropic compressibilities are negative in all range of mole fraction, and decrease when the 1-alkanol increases.
This behaviour is due to the formation of hydrogen bonds between the –OH group of the 1-alkanols and the etheric oxygen of the dibutyl ether. The values obtained for the isentropic compressibilities and speeds of sound support this conclusion.
Presented Monday 17, 13:30 to 15:00, in session Thermodynamics (T2-1P).
