A Relation between Ion-exchange Selectivity Coefficient and Degree of Distribution for Model Compounds in Solvent Extraction

1968 ◽  
Vol 41 (8) ◽  
pp. 1757-1760 ◽  
Author(s):  
Tadao Kenjo ◽  
Takuji Ito
1992 ◽  
Vol 4 (1) ◽  
pp. 49-54 ◽  
Author(s):  
Refat M. Hassan ◽  
S. A. El-Shatoury ◽  
M. Th. Makhlouf

The separation of divalent metal ion mixtures has been investigated chromatographically on columns of either gel or sol forms of alginate polyelectrolyte. Separation was obtained in the form of narrow sharp zones for the metal ions. Ion exchange selectivity indicated that Cu2+ ions were most strongly retained among the divalent metal ions studied. The factors which affect the ion exchange selectivity, such as the strength of chelation and the mobility and radii of the metal ions, are discussed. The selectivity coefficient for the separation of a mixture of Cu2+ and Co2+ ions on columns of calcium alginate gel or sodium alginate sol was determined and found to be 1.9 ± 0.1 in both ion exchangers at 25°C.


2000 ◽  
Vol 15 (12) ◽  
pp. 2849-2856 ◽  
Author(s):  
Masamichi Tsuji ◽  
Hitoshi Mimura

Am3+ and Eu3+ /alkali cation exchange selectivity was studied on mordenite and zeolite L at 25 to 60 °C to examine the effect of their openings of ion-exchange sites. The corrected selectivity coefficient at the infinitesimal exchange increased in the order of Eu3+ < Am3+ on mordenite and Am3+ < Eu3+ on zeolite L. The selectivity reversal did not reflect the effect of the ionic form, but reflected the dimension of the opening of the ion-exchange site and charge of trivalent cations, since the crystal ionic radii of alkali cations were much smaller than the openings of these zeolites (7–8 Å).


2019 ◽  
Vol 61 (6) ◽  
pp. 724-727
Author(s):  
M. Yarmohammadi ◽  
M. Mirzaei ◽  
A. Samadi-Maybodi

Processes ◽  
2018 ◽  
Vol 6 (8) ◽  
pp. 112 ◽  
Author(s):  
Wei Xing ◽  
Man Lee ◽  
Seung Choi

Ion exchange and cementation experiments were done to separate silver(I) from a raffinate containing silver(I), nickel(II), and zinc(II) and small amounts of copper(II) and tin(II). The raffinate resulted from the recovery of gold(III), tin(II) and copper(II) by solvent extraction from a leaching solution of anode slime. Ion exchange with anionic resins was not effective in separating silver(I) because tin(II) and zinc(II) were selectively adsorbed into the anionic resins. It was possible to separate silver(I) by cementation with copper sheet. Treatment of the cemented silver with nitric acid solution increased the purity of silver(I) in the solution from 50.9% to 99.99%. Adjusting the pH of the AgNO3 solution to higher than 6, followed by adding ascorbic acid as a reducing agent, led to the synthesis of silver particles with micron size.


2009 ◽  
Vol 73 (3) ◽  
pp. 928-942 ◽  
Author(s):  
Christophe Tournassat ◽  
Hélène Gailhanou ◽  
Catherine Crouzet ◽  
Gilles Braibant ◽  
Anne Gautier ◽  
...  

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