Liquid-Liquid Equilibrium Phase Diagrams of Polyethyleneglycol + Sodium Tartrate + Water Two-Phase Systems

PELLEGRINI MALPIEDI, LUCIANA; FERNÁNDEZ CINTIA; PICÓ GUILLERMO; NERLI, BIBIANA

JOURNAL OF CHEMICAL AND ENGINEERING DATA

AMER CHEMICAL SOC

Año: 2008 vol. 53 p. 1175 - 1178

0021-9568

The phase diagrams of aqueous two-phase systems formed by water, sodium tartrate, and polyethyleneglycol of different molecular weights (600, 1000, 2000, 4000, 6000, and 8000) were determined at 298 K. The effect of NaCl on the liquid?liquid equilibrium was also analyzed. The binodal curves were satisfactorily described using a four-parameter sigmoidal equation. The tie lines were determined by combining a colorimetric method and density measurements. The reliability of the measured tie line compositions was ascertained by the Othmer-Tobias and Bancroft correlation equations.