Liquid–liquid equilibrium of 1-propanol, 2-propanol, 2-methyl-2-propanol or 2-butanol + sodium sulfite + water aqueous two phase systems

Liquid–liquid equilibrium of 1-propanol, 2-propanol, 2-methyl-2-propanol or 2-butanol + sodium sulfite + water ternary systems was studied at T = 298.15 K. Both binodal curves and tie-line compositions for the studied systems at T = 298.15 K were also reported. Furthermore, cloud-point data as a function of alcohol mole fraction at the temperature range of T = 293.15–323.15 K was measured to study the effect of temperature. Effect of different alcohols and different anions were also studied considering the intermolecular interaction. Also, the use of the Setschenow-type equations to study the slating-out effect of the mentioned ATPSs was discussed. Additionally, the segment based Wilson equation was generalized to represent the mixed organic–aqueous solvent electrolyte systems and successfully used for the correlation of binary and ternary data. The restricted binary interaction parameters were also reported. The result of the generalized Wilson model in the correlation of the tie-line compositions was compared with the e-NRTL model. The obtained results show that the simpler generalized Wilson equation can represent the tie-line compositions better than the e-NRTL model.

► Phase diagrams of alcohol + sodium sulfite + water were reported.
► Salting-out ability of different salts and alcohols was discussed.
► Wilson model was generalized to correlate the tie-line data.
► Binary interaction parameters of Wilson and e-NRTL models were reported.