Continuous counter-current ion-exchang

A number of other continuous counter-current ion-exchange contactors have been developed s-based, for instance, upon mixer-settlers, Archimedean screws, etc., but these are hkely to involve too high a degree of attrition of the resin or the frequent occurrence of blockages, to be satisfactory in a production plant. 

Comparison with solvent extraction. Although a substantial effort has been devoted to the development of satisfactory continuous counter-current ion-exchange processes for metal extraction, it is debatable whether any of... 

Modolo, G., Asp, H., Vijgen, H., Malmbeck, R., Magnusson, D., Sorel, C. 2008. Demonstration of a TODGA-based continuous counter-current extraction process for the partitioning of actinides from a simulated PUREX raffinate, Part II Centrifugal contactor runs. Solvent Extraction and Ion Exchange 26(1) 62-76. 

Slater MJ. The relative sizes of fixed bed and continuous counter-current flow ion exchange equipment. Trans IChemE 60 54-58, 1982. 

Continuous ion-exchange separation technology, which adopts counter-current processing in a rotating turntable, is currently making an impact and 70% of the world s lysine manufacture units use this technology. 

Fig. 3.9. Schematic diagram of Higgins continuous ion-exchange contactor, showing mechanism of counter-current solid-liquid flow (Higgins, I. R. U.S.A.E.C. Report TID 7501).

Higgins, I. R. and Roberts, J. T. A (Counter-current Solid Liquid (Contactor for (Continuous Ion-Exchange. Chemical Engineering Progress Symposium, Ser. 14, vol. 50, p. 87 (1954). 

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