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乳化液膜是溶劑萃取法的改良，萃取與剝脫之操作同時進行，具有很大之比表面積與
很短之擴散距離。故濃縮與分離之速率很快。
利用鈷（60）離子，小於pH=2之條件下測定乳化液膜之穩定度，非常方便。液膜之穩
定度與外部水溶液之回收體積受液膜之黏度，乳化劑之濃度、溫度，HDEHP （二（2-
乙基己基）磷酸）之濃度，乳化劑之種類與內部水溶液之體積、酸度、電解質濃度等
之影。HB-40 與石臘油皆適宜做液膜之基體。煤油、環己烷，六氯丁二烯皆為良好之
稀釋劑。在安定之乳化液膜其破裂百分率應小於1 ％，回收體積為95㏄。
黏度略大之HB-40 與30％之煤油混合有機相，銪離子與HDEHP 平衡之方程為：
（圖表省略）
在25℃之K值為4.0×10-1。銪離子在液膜內傳遞屬於交錯方式傳遞，其具有向高濃度
銪離子方向傳遞之傾向，而氫離子向低濃度氫離子方向傳遞之傾向。驅使傳遞之動能
為氫離子濃度，傳遞最初通量Jco 與 A＋ B＋★成線型關係。而擴散係數10-6cnf。
銪離子在石臘油膜傳遞之通量受液膜之濃度，乳化劑之濃度，HDEHP 之濃度，乳化油
滴之使用量，乳化劑之種類，攪拌速度，外部水溶液之氫離子，氯化鈉，酒石酸，與
銪離子等濃度影響。
較大黏度之HB-40 與30％稀釋劑有機相中鑭系金屬離子之平衡方程式與銪離子一樣，
相同稀釋劑對每種三價金屬離子平衡常數大小順序為鎦（Ⅲ）離子＞鐿（Ⅲ）離子＞
鋱（Ⅲ）離小＞銪（Ⅲ）離子。pH=1.5時，銪與鋱離子在液膜中回收率不受時間之增
長而增加，且鎦與鐿離子隨時間之變化而增加，因此銪與鋱離子可由鎦與鐿離子中分
離。pH=3時銪離子在各種稀釋劑之回收率隨時間之增長而增加，8 分鐘以前其回收率
大小順序為氯仿＞四氯化碳＞六氯丁二烯＞煤油＞環己烷。
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Separation of Europium(III) with di-2-ethylhexylphosphoric acid by
Surfactant Liquid Membrane.
Liquid membrane is the improvement of liquid-liquid solvent extraction.
Extracting and stripping substances are operated at the same time. Large
specific area and thin thickness make the rate of concentration and
separation fast.
It is very convenient for using cobalt 60 to measure the stability of
liquid membrane when the pH is less than 2. The stability of the membrane
and the recovery volume of outer aqueous solution depend on viscosity of
membrane, emulsifier concentration, temperature, HDEHP concentration, the
kinde of emulsifier and volume, acidity and electrolytic concentration of
inner aqueous solution.
HB-40 and paraffinic oil are suitable as a base of liquid membrane.
Kerosene, cyclohexane and hexachloro-1, 3-butadiene are good kiluents. The
membrane broke up less than 1 % and about 95cc of recovery volume was
found.
Eu3+ extracted with HDEHP in organic phase containing 30 % kerosene and
HB-40 of high viscosity indicates the equilibrium as follows:
（圖表省略）
The equilibrium constant is 4.0 x 10-1 at 25℃.
In the membrane, europium ion transports as the form of contertransport.
The diffusion tendency for Eu3+ is toward high concentration and for H+ is
toward low concentration. The driving force of europium complex is due to
the different hydrogen ion concentration between inner and outer aqueous
solution of the membrane. The initial flux of the complex is linearly
dependent of A + B + ★ The diffusion coefficient of the complex is about
10-6 cm2/sec.
The flux of europium ion is affected by viscosity of the membrane,
eumlsifier concentration, HDEHP cocentration, the amount of emulsion drop,
the kind of emulsifier, stirring rate, and the concentration of hydrogen
ion, sodium chloride, tartaric acid and europium ion.
The equilibrium equation of lanthanide ion in the highly viscous HB-40 and
30% diluents is the same as that of europium ion. The order of equilibrium
constant for the ions at each diluent is Lu3+ > Yb3+ > Tb3+ > Eu3+.
When pH of outer aqueous solution is 1.5, the recovery rates of europium
and terbium ions do not increase with time, but thos of leutetium and
yetterbium ion do, so europium and terbium ions can be separated from the
leutetium and ytterbium at this pH.
At pH-3, the recovery rate of europium ion in different diluents goes up
with time. Within 8 minutes the order of recovery rate in different
diluents is chloroform > charbon tetrachloride > hexachloro-1, 3-butadiene
> kerosene > cyclohexane.
（圖表省略）
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