Phase behaviour of water plus nonionic surfactant systems: experiments andmodelling applying the Peng-Robinson equation of state with the Wong-Sandler mixing rules and the UNIQUAC g(E)-model
Esj. Rudolph et al., Phase behaviour of water plus nonionic surfactant systems: experiments andmodelling applying the Peng-Robinson equation of state with the Wong-Sandler mixing rules and the UNIQUAC g(E)-model, FLU PH EQUI, 173(1), 2000, pp. 81-96
In this work, experimental liquid-liquid phase equilibrium data of the syst
ems water+C6E4 and water+C7E4 at pressures up to 100 MPa and in a temperatu
re range between 315 and 355 K are presented. Further, modelling results of
several water+nonionic surfactant systems at various pressure are shown. T
he investigated binary water+surfactant systems contained besides C6E4 and
C7E4 the following other surfactants: C4E1, C6E3 , C7E3, and C7E5. As a mod
el, the Peng-Robinson equation of state with the Wong-Sandler mixing rules
and the UNIQUAC g(E)-model was used. The model parameters were adjusted to
experimental phase equilibrium data at 0.1 MPa. The resulting parameter set
s were used for the prediction of the phase behaviour at higher pressures.
The fitted model expresses the experimentally found type of phase behaviour
quite correctly. However, the pressure influence on the phase behaviour of
these systems could only be described qualitatively. (C) 2000 Elsevier Sci
ence B.V. All rights reserved.