Studies on Ion-exchange Resins. XIII. Selectivity Coefficients of Quaternary Base Anion-exchange Resins Toward Univalent Anions

Tc-99 Ion Exchange Resin Testing

“…It was previously demonstrated that this material has the capability to remove significant amounts of perchlorate (ClO 4 -) and pertechnetate (TcO 4 -) from contaminated groundwater (Gu et al 2000a. In fact, Purolite A530E is currently being used to remove TcO 4 -from the contaminated groundwater at the U.S. Department of Energy's Paducah Gaseous Diffusion Plant site in Kevil, Kentucky (Gu et al 2000b -preferentially over the other anions in an aqueous solution (Gregor et al 1955). This bias can be enhanced by chemical modification of the resin, including altering the size and shape of the cationic exchange sites and the polymer cross-linking density.…”

Perchlorate Selectivity of Anion Exchange Resins as Evaluated Using Ion-Selective Electrodes

“…For example, only one of these papers described the most important parameter of the selectivity coefficient; log KCl ClO4 : 2.72 for QPEI-4 (hyperbranched polyethyleneimine-type resin), 2.78 for A-530E (styrene divinylbenzene-type resin). 9 The coefficients of varying anions on the conventional resins were independently studied by several groups in the 1950s [10][11][12][13] and later. 14,15 These values were in reasonable agreement with each other except for perchlorate, for which extremely different values were reported: for example, log KCl ClO4 : 2.18 and 1.5 for type I (with trimethylaminomethyl group, cross-linking of 8%); 12,15 1.4 for type II (with 2-hydroxyethyldimethylaminomethyl group).…”

“…14,15 These values were in reasonable agreement with each other except for perchlorate, for which extremely different values were reported: for example, log KCl ClO4 : 2.18 and 1.5 for type I (with trimethylaminomethyl group, cross-linking of 8%); 12,15 1.4 for type II (with 2-hydroxyethyldimethylaminomethyl group). 11 Even a variation in selectivity coefficient according to the relative exchange was suggested and discussed. 11,[14][15][16][17] Under such circumstances, a recent paper described the coefficient only at the molar fraction of ClO4 -of 10 -4 level in the resin phase.…”

“…11 Even a variation in selectivity coefficient according to the relative exchange was suggested and discussed. 11,[14][15][16][17] Under such circumstances, a recent paper described the coefficient only at the molar fraction of ClO4 -of 10 -4 level in the resin phase. 18 The modern handbooks do not include the coefficient for perchlorate.…”

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

“…[3][4][5][6] However, Cobalticinium picrate ((C5H5)2CoOC8H2(NO2)3) was obtained by the method mentioned in a previous paper.7)…”