鹽析現象降低溶劑間互溶的效應

The Phenomenon of Salting Out and Reduces the Effect that Dissolves Each Other Among Solvents

顏書亞(Shu - Ya Yen)

指導教授 ： 段葉芳

國立臺北科技大學/工程學院/化學工程所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00058

摘要

這個實驗的部分是探討乙酸正丁酯－正丁醇－水 三成份系統受到不同種類的鹽類而產生鹽析效應的影響，因此在此25℃下，用乙酸正丁酯－正丁醇－水所設計的系統，分別加入飽和磷酸鈉、磷酸氫鈉濃度下，進行液液平衡實驗得到各成份的莫耳分率。由實驗結果得到的液液平衡相圖中，兩相的不互溶區很明顯的變大了，並發現此兩種鹽產生的鹽析效應的大小關聯性。 這個理論的部分以 TTK - Wilson 活性係數模式來描述溶液到底有多偏離理想溶液，為了模擬鹽效應在混合溶劑系統之液液平衡，以TTK-Wilson活性係數模式作理論模擬結果與實驗的結果相符合。

關鍵字

磷酸鈉 ； 磷酸氫鈉 ； 鹽析效應 ； TTK-Wilson 活性係數模式

並列摘要

In chemical industry, separation processing is usually considered as a useful technology for the optimal design of unit operation and processing. Adding diverse electrolytes (salts) with different amounts can separate the mixture, n-Butyl Acetate－n-Butanol－water, in esterification through salting analysis processing. The ester type of products with a higher purity can be produced or designated for further purification processing.
This research is consisted of experimental and theoretical investigations. In the experimental part, the salting analysis processing in a mixture of n-Butyl Acetate－n-Butanol－water under temperature 25℃ is individually performed with two salts, sodium phosphate and sodium phosphate dibasic.The equilibrium charts of liquid-liquid phase analyzed from the experimental results show that an extending non-dissolution area for two solvents is obviously found after adding salts.The results also reflect the same trend occurring at a decreasing solubility for both n-Butyl Acetate－water and n-Butanol－water. The effect of salting analysis processing deceases in the order of sodium phosphate and sodium phosphate dibasic.
To simulate the liquid-liquid phase equilibrium in mixing solvents, the TTK - Wilson activity coefficient model is adopted to describe the deviation between the ideal solvent and the solvent in our research. By computing the liquid-liquid phase equilibrium of electrolytes in mixing solvents, the experimental results show a high degree of consistence, an average deviation of less than 0.8%, with theoretical prediction.

並列關鍵字

sodium phosphate ； sodium phosphate dibasic ； Salting Effect ； TTK-Wilson ； activity coefficient model

參考文獻

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