Abstract:

Both the water-rich phase(water phase)and the see-butanol-rich phase(see-butanol phase)can be form ed when adding KF or K₂CO₃ into the see-butanol-water system.In this paper,the data about the liquid-liquid equilibrium (LLE)of see-butanol-water-KF and see-butanol-water-K₂CO₃systems are measured at 25℃,showing that the see·-butanol phase contains negligible salt and the water phase contains negligible see-butanol when the
mass fraction of KF or K₂CO₃ in the water phase is not less than 26.38% or 28.76% ,respectively.Thus,water can be eficiently separated from the see-butanol-water system by adding KF or K₂CO₃ into the mixture.Moreover,a theoretical calculation of LLE data is carried out by using the Pitzer equation and the UNIQUAC equation to get the water activities respectively in the water phase and in the see-butanol phase.The calculated results are proved to be in good agreement with the experimental ones,the absolute mean deviations between the experimental data and the calculated results being 1.57% in the water phase and 0.33% in the see-butanol phase for see-butanol-wa-ter-KF system.and being 1.40% in the water phase and 0.39% in the sec-butanol phase for sec-butanol-water-K₂CO₃ system.

Key words: see-butanol-water-KF system, see-butanol-water-K₂CO₃ system, liquid-liquid equilibrium, Pitzer equation, UNIQUAC equation, theoretical calculation, separation