正丁醇-硫酸铵-水液液平衡数据的测定及关联

Measurement and correlation of liquid-liquid equilibria of n-butanol-ammonium sulfate-water

采用浊点法和饱和密度法测定了正丁醇+硫酸铵+水部分互溶体系在25℃和60℃下的溶解度数据和液液相平衡数据。在相图的基础上讨论了温度对正丁醇的相形成能力的影响。此外,采用Othmer-Tobias和Bancroft方程以及Setschenow-type方程关联和预测了2个温度下的液液相平衡组成。结果表明:温度升高,二相区增大,结线长度增大,正丁醇相中硫酸铵的质量分数减小,低于0.3%,相应水相中的正丁醇的质量分数降低。2个模型的关联结果与实验结果均吻合较好,偏差均小于1.7%。

Binodal data and liquid-liquid equilibrium data for the partially miscible system of n-butanol-ammonium sulfate-water were measured using cloud point method and saturation density method at 25 ℃ and 60 ℃. The effect of temperature on the phase-forming ability of n-butanol was also discussed based on the phase diagrams. Furthermore, the liquid-liquid equilibrium compositions of the system were correlated and predicted with Othmer- Tobias and Bancroft equations and Setschenow-type equation at the two temperatures. It shows that both the two- phase region and tie line length increase, and the mass fraction of ammonium sulfonate in organic phase decreases with temperature rise, which is below O. 3%. The corresponding mass fraction of n-butanol in water phase decreases. The results obtained from the correlation are very satisfactory in accordance with root mean square deviations, which are always below 1.7%.