Ion-exchange studies

M Qureshi et al., Recent progress in ion-exchange studies on insoluble salts of polybasic metals Separation Sci. 1972, 7, 615... 

Ion-exchange studies of complex formation. Y. Marcus, Ion Exch. Solvent Extr., 1966, 1, 101-138 (63). 

Holroyd, A. Salmon, J. E. (1956). Ion-exchange studies of phosphates. Part I. Ion-exchange and pH-titration for detection of complex formation. Journal of the Chemical Society 269-72. 

KCl solution for 24 hours. After being removed from the salt solutions, the membranes were rinsed thoroughly with distilled, deionized water. The salt solutions were analyzed with a Varlan 175 series atomic absorption spectrometer (AAS). Na and K concentrations were determined using the 590.8 nm and 768.5 nm absorption bands, respectively. Before and after the ion-exchange studies, the membranes were dried and analyzed with ESCA and NAA. 

Burba, P. (1994) Labile/inert metal species in aquatic humic substances an ion-exchange study. Fresenius J. Anal. Chem., 348, 301-311. 

Schubert, J. Ion exchange studies of complex ions as a function of temperature, ionic strength, and presence of formaldehyde, J. Phys. Chem. 56, 113-118 (1952). 

Numerous determinations have been made of the stability constants of sulfate complexes of plutonium(IV), and the results vary by three orders of magnitude. The most plausible values (14) have come from careful ion exchange studies at I = 2 M and 25°, which indicate the presence of two species, Pu(S0i+) and Pu(S0i )2, with stepwise stability constants of 6.6 X 10 and 5.8 X 10, respectively. This Ki is in satisfactory agreement with the value 4.6 X 10 obtained potentiometrically at I = 1 M and 25° ( ). Spectrophotometric and electrophoretic studies indicate that plutonyl(VI) forms complexes containing as many as four sulfate groups, with anionic species predominating at sulfate concentrations above 1 M (15). The monosulfato complex has a reported stability constant of 14.4 as determined by extraction studies at I - 2 M and 25° (16). 

Fardy, J. J., and Buchanan, J. M. An ion exchange study of the sulfate complexes of plutonium(III), J. Inorg. Nucl. 

Foreman, J. K., and Smith, T. D. The nature and stability of the complex ions formed by ter-, quadri-. and sexa-valent plutonium ions with ethylenediaminetetraacetic acid. Part I. pH titrations and ion exchange studies, J. Chem. Soc.,... 

The equivalence law governing the phenomenon was established in the early scientific history of the subject, as also was the fact that some ions were more easily exchanged than others in other words ion exchangers showed greater selectivity or affinity for different ions. That an exchanger could be chemically synthesized proved to be of the utmost importance it is for this reason that ion exchange studies and applications have reached such an advanced state today. 

Ion Exchange Studies. Ion exchange has been used previously to probe the different types of Eu(III) and interactions with unfractionated HA as a function of metal... 

The extraction chromatography of the actinides has been reviewed and the treatment of zirconium phosphate sorbent for use in the separation of actinides has been described. An ion exchange study of the sulphate complexes of plutonium(iii) at 25 °C in IM and 2M perchloric/sulphuric add media found no evidence for the participation of protonated hgands in the complex formation. In the range... 

The element francium is formed in the natural radioactive decay series and in nuclear reactions. All its isotopes are radioactive with short half-lives. Precipitation reactions and solubility and ion-exchange studies have shown that the ion behaves as would be expected from its position in the group. 

Synthetic zeolites which have been resolved include the zeolite type L (14) and the zeolite Q (13), both of which have open frameworks and should have important catalysis application. Ion exchange studies (71) have contributed to an understanding of the synthetic zeolite T (19), which appears to be structurally related to the minerals offretite and erionite. 

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