摘要 氯化四丁基銨鹽 Bu4NCl 是一常用的相轉移催化劑,在某些酯化反應特具功效。但由於氯化四丁基銨鹽難以季化合成,故利用電解﹣電透析溴化四丁基銨鹽 Bu4NBr 以合成之。 本研究首先對於三丁胺 Bu3N 與碘丁烷 BuBr 之季化反應合成溴化四丁基銨鹽 Bu4Br。選擇一既容易進行反應且容易結晶之溶劑,本實驗選擇 DMA 當溶劑,其反應莫耳比為 Bu3N : BuBr : DMA = 1 : 1 : 3.73,溫度控制在 100℃,反應 16 小時候,冷卻析出結晶鹽,過濾後取出。其濾液再加入適當溶劑,利用溶解度與介電常數之不同,可再次析出結晶鹽。如此循環可將產率提高,亦可得到高純度之溴化四丁基銨鹽 Bu4NBr。 本實驗裝置為四隔室型,陽極採用鉑鈦合金電極板,陰極採用不鏽鋼電極板。陽極室通入 NaCl 水溶液,濃縮室通入 NaBr 水溶液,淡化室通入 Bu4NBr 水溶液,陰極室通入 HCl 水溶液,配合陽離子交換膜 Nafion NX982TX 及陰離子交換膜 Asahi AMV。在陽極室與濃縮室溶液濃度固定不變情況下,則由實驗所得數據可知,電流效率、電壓效率與淡化室液、陰極室液濃度、電流密度、流速及各隔室間寬度之關係。以及電能消耗與淡化室液、陰極室液濃度、電流密度、流速及各隔室間寬度之關係。 同時由無因次的分析,可得電流效率和電壓效率與系統操作變因有著無因次之關係。 Abstract Tetrabutylammonium chloride is a phase transfer catalyst which is especially useful in some solid-liquid phase transfer catalyzed esterifications. It is not feasible to synthesize this compound by quaternization or by nucleophilic double displacement because that both the quaternization rate constant and the displacement equilibrium constant are very small. The tetrabutylammonium chloride can be prepared by the electrodialysis of tetrabutylammonium iodide. The advantages of the process are that the iodide can be easily obtained by quaternization and that only a cation exchange membrane is need. But, the disadvantages are that it is slightly soluble in water and the produced iodine would be absorbed on the anode. This project proposes a new electrodialysis process for synthesizing the tetrabutylammonium chloride. From the derived current density equation and the applied voltage equation in this project, it is inspected that the factors affecting both the current efficiency and the voltage efficiency are: current density, concentration, flow velocities of electro-lytes and width of compartments. From the two equations, the dimensionless correlations of two efficiencies with the operating variables are also proposed. The parameters in the equations will be ob-tained in this project so as to get the basic information for synthesizing tetrabu-tylammonium chloride.