The industrial application of ion-exchange (IE) processes is growing progressively. In many instances the IE technology can successfully substitute existing large-scale industrial processes which do not satisfy modern ecological standards. The requirements that the IE technology should have to create a competitive process are high efficiency and ecological safety. However, the general scheme of "standard" IE processes remains practically unchanged during the last decades and comprises the following auxiliary operations~(1,2): 1) preparation of stock solution; 2) concentration of solution after the IE treatment (e.g., by evaporation); 3) recovery of the purified product (e.g., by crystallization); 4) regeneration of ion exchangers and auxilliary reagents for reuse; 5) neutralization of aggressive wastes, and some others. Several approaches can be applied to eliminate some of these auxiliary operations to improve the efficiency of the process due to significant saving in chemicals, energy, manpower, minimization of wastes, etc. One of those is based on the application of dual-temperature IE processes~(3-6) which allows one to exclude auxiliary operations 4 and 5. Hence, a practically reagentless and wastefree, separation process can be designed~(7-12). Another route to avoid the above auxiliary operations (e.g., 2 and 3) is based on a combination of the IE conversion and concentration processes into one stage. Frontal IE chromatography~(13,14) and reverse frontal separation~(14,15) are applicable for this purpose. In certain instances, both of those IE separation techniques allow concentrating the target substance up to the level exceeding its solubility at a given temperature. Moreover, this supersaturated solution (SS) remains stable for a long period, and after leaving the column it crystallizes spontaneously. This allows for designing a practically ideal process where a crystalline product is obtained directly after the IE treatment. This phenomenon - known as Ion-Exchange-Isothermal-Supersaturation (IXISS) - has been discovered by Muraviev~(16). This paper reports some of the results obtained by tailored application of dual-temperature IE and IXISS effect to design highly-efficient and ecologically safe IE technologies which can be considered as a successful alternative to existing large-scale industrial processes.
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