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Vladimir Rohac, Kvetoslav Ruzicka, Vlastimil Ruzicka, Dzmitry H. Zaitsau, Gennady J. Kabo, Vladimir Diky, Karel Aim
Abstract
Measurements of vapour pressure in the liquid phase and of enthalpy of vaporisation and results of calculation of ideal gas properties for diethyl phthalate are reported. The method of comparative ebulliometry, the static method, and the Knudsen mass loss effusion method were employed to determine the vapour pressure. A Calvet type differential microcalorimeter was used to measuer the enthalpy of vaporisation. Simultaneous correlation of vapour pressure, of enthalpy of vaporisation and of difference in heat capacities of ideal gas and liquid/ solid phases was used to generate parameters of the Cox equation that cover both the (vapour + solid) equilibrium (approximate temperature range from 220 K to 270 K) and (vapour + liquid) equilibrium (from 270 K to 520 K). Vapour pressure and enthalpy of vaporisation derived from the fit are reported at the triple-point temperature Tau = 269.92 K (p= 0.0029 Pa, delta 6vapHm=85.10 kJ molu-1), at T=298.15 K (p=0.099 Pa, delta vap6uHm=82.09 kJ mol^u-1), and at the normal boiling vaporisation are compared with literature data.
Rohac, V.
, Ruzicka, K.
, Ruzicka, V.
, Zaitsau, D.
, Kabo, G.
, Diky, V.
and Aim, K.
(2004),
Vapour Pressure of Diethyl Phthalate, Journal of Chemical Thermodynamics, [online], https://doi.org/10.1016/j.jct.2004.07.025
(Accessed October 13, 2025)