Liquid–liquid phase equilibrium of MgSO₄ and PEG1500 aqueous two-phase system

Abstract

In this work, PEG 1500, MgSO₄ and water were used to create an aqueous two-phase system and the effect of temperature was surveyed by obtaining binodal data and equilibrium data at 35, 40 and 45°C; compositions of mixture were obtained by atomic absorption spectrometer and refractometery method. Results showed that with increasing temperature, the solution tends to attain a two-phase region and the slope and length of tie lines increases. Modified Wilson equation was used to correlate this system, adjustable parameters were evaluated directly from experimental data and good agreement with experimental data was obtained. The overall average relative deviation was found to be less than 6%.

Keywords:

• aqueous two-phase systems
• polymer
• salt
• Wilson-NRF model
• LLE