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自从综论“液体离子交换剂在无机分析中的新近应用”于1964年在《Talanta》上发表以来,这一类型的试剂仍在继续发展着。液体离子交换是溶剂萃取的一种特殊情况,它亦涉及溶质在不混溶的两相间选择性的转移,其区别在于溶剂萃取需要中性物的形成,不论是螫合物、离子对、或不离解的化合物,而液体离子交换仅指在水相和有机相之间发生一种离子对另一种离子交换时,形成离子对的情况。转移的程度,或离子交换萃取度正比于溶剂中离子交换剂的浓度;所得到的分配系数与溶剂萃取中所应用的相类似。液体离子交换剂的选择性和分配系数的变化与pH、温度、盐的浓度、有关离子的电荷数、络离子和竞争离
This type of reagent has continued to evolve since the review “Recent Applications of Liquid Ion Exchangers in Inorganic Analysis” was published in “Talanta” in 1964. Liquid ion exchange is a special case of solvent extraction and also involves the selective transfer of solutes between immiscible two phases, the difference being that solvent extraction requires the formation of neutrals, whether they are chelates, ion pairs, or A compound that does not dissociate, whereas liquid ion exchange refers only to the formation of an ion pair when one type of ion-to-ion exchange occurs between the aqueous and organic phases. The degree of transfer, or the degree of ion exchange extraction, is proportional to the concentration of ion exchanger in the solvent; the resulting partition coefficient is similar to that used in solvent extraction. Selectivity and partition coefficient of liquid ion exchangers vary with pH, temperature, salt concentration, number of charges associated with ions, complex ions and competition