The electromigration of ions in the ion-exchange filter paper impregnated with pulverized ionexchange resin is considered to be contributed by the ionexchange adsorption and the electromigration behavior of ions.
In this study, an apparatus to be used for ordinary paper electrophoresis was used for determining the mobility of alkaline earth metal ions under constant voltage.
The ion-exchange papers used for the experiment were the Amberlite SA-2 and WA-2 which had been conditioned with acid, alkali and methanol.
The ionic electromigration in the ion-exchange papers showed lower velocity and less tailing than in the ordinary paper. The ionic mobility on the filter paper decreased in the order of Ba²⁺>Sr²⁺, Ca²⁺>Mg²⁺ which was the same mobility in free solution. The mobility on the sulfonic Amberlite SA-2 paper was in the order of Sr²⁺, Ca²⁺>Mg²⁺>>Ba²⁺.
This study revealed that the ion-exchange adsorption had a remarkable effect on the electromigration behavior of ions and that this method was applicable to the separation of ions and the clarification of ionic transport behavior across the ion-exchange membrane.

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A study was conducted on the separation of uranium from sea water. In this study, the artificial sea water which was prepared by Kalle so as to contain 1mg/l of uranium was used, and uranium was determined by colorimetric method using Arsenazo III.
The separation of uranium was carried out by formation of insoluble substances with phosphate. By this procedure, about 90% of uranium in the sea water was collected into precipitates of phosphate. This method proved useful for the separation of uranium from sea water.

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In this paper, the distribution of dissolved species in sea water was calculated by using the known stability constants involving Ca²⁺, Mg²⁺, Na⁺, K⁺, SO₄^2-, CO₃^2-, HCO₃^-, PO₄^3-, HPO₄^2-, H₂PO₄^-, and F^-. As a first method, the calculation was carried out by solving the equations of multi-components using the stability constants in salt solution. As a second method, the calculation was done by using the stability constants in zero of ionic strength corrected by activity coefficients. The activity coefficients were estimated from Kielland's formula. Most of the distribution gained by the second method approximated to those values obtained by Garrels.
Phosphate was strongly complexed, and about 90 percent of the phosphate was dissolved as HPO₄^2-and paired species of HPO₄^2- to various cations. The remaining about 10 percent of phosphatg existed in the form of CaH₂PO⁴⁺. Nearly a half of F was paired with Mg.

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1) The permselectivity coefficient (T^B_A) between two ions, B and A, of the same electric charge, but of different valence, can be expressed by Equation (15):
(15)
where
uA, uB: transfer velocity of A and B ions across membrane
C_0A, C_0B: concentration of A and B ions in the bulk of dialysate
K^B_A: separation factor
i: current density
δ: thickness of diffusion layer
D_A, D_B: diffusion constant of A and B ions in dialysate
t±: total transport number of A and B ions in membrane
t_A, t_B: transport number of A and B ions in dialysate
F: Faraday's constant
By Equation (15), iδ can be regarded as one parameter for T ^B_A.
2) Equations (20) and (21), which express the critical current density (i_crit) and the critical permselectivity (T^B_{A crit}), can be derived.
i_crit=F/δ·D_AC_OA+D_BC_OB (20)
(21)
3) The permselectivity coefficient (T^B_A) and separation factor (K^B_A) at the moment when the concentration of B ion in the bulk of dialysate (C_0B) becomes equal to that in the diffusion layer on a membrane surface (C_SB), can be given by Equations (23) and (26), respectively. Further, Equation (28) giving the separation factor (KBAcrit) at the moment when TBA becomes equal to T^B_A crit, is also derived.
4) Results of numerical analysis by using Equations (15),(20) and (21) are shown in Fig. 8, 9 and 11. From these results, the tendency of changing in the value of T^B_A with current density (i), with T^B_A successively approaches to and reaches T^B_Acrit at the critical current density (i_crit), becomes clear.
The very similar tendency of changing in T^B_A value with current density can be found among the results of our previous experiments. This indicates that the assumption on a mass transfer model across an ion exchange membrane is appropriate.
5) By Equation (15), the concentration of A and B ions in the solution of diffusion layer (C_SA and C_SB) and the value of K^B_A, as well as the value of T^B_A, is calculated. And, relations between these calculated values and the values of T^B_A, K^B_A and K^B_Acrit obtained by Equations (23),(26) and (28) are discussed.
It it found that:
(1) When K^B_A>K^B_AcritT^B_Aapproaches to T^B_Acrit with a value larger than T^B_Acrit, but when K^B_A<K^B_Acrit, T^B_A approaches to T^B_Acrit with a value smaller than T^B_Acrit.
(2) When K^B_A<K^B_A, C_SB is larger than C_0B, but when K^B_A becomes larger than K^B_A with an increase in current density, C_SB becomes smaller than C_0B. At the critical current density (i_crit), both C_SB and C_SA reach to zero.

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