Experiment and correlation of liquid-liquid equilibria of an aqueous salt polymer system containing PEG6000 + sodium citrate

Liquid-Liquid equilibrium data were obtained for an aqueous two-phase system containing poly(ethylene glycol)-6000 (PEG6000) + sodium citrate + water at three different temperatures, 293.15, 303.15, and 313.15 K. An empirical equation relating the concentrations of PEG6000 and sodium citrate was used to fit the binodal curve, and the coefficients were estimated for the corresponding temperatures. The effect of temperature on binodal and tie line data was studied. The Othmer-Tobias and Bancraft equations were used to correlate the tie line compositions, and the parameters are reported. © 2007 American Chemical Society.