Criteria For The Choice Of Organic Phase:

We are now at the concluding stages of this unit and have learnt that a variety of extractants are available for the extraction / separation of metal ions. There are various aqueous and organic parameters which affect the extraction. An intelligent utilization of the variation in some of the parameters can result into separation of metals with high separation factors. This makes the technique to be very useful for various industrial operations and it finds applications in hydrometallurgy, nuclear fuel reprocessing and environmental engineering (decontamination of metal loaded waste). Because of the industrial utility of solvent extraction, we have to define the parameters of the system in such a way that the process has industrial viability. The success of a solvent extraction system depends upon the composition of both the contacting phases i.e., aqueous and organic. The organic phase contains the extractant alone or the extractant dissolved in a suitable diluent. In this context, it may be important to spell out the criteria for the choice of organic phase. Some of these criteria may look innocuous or insignificant when the technique is being applied for simple analytical separations at bench level but they may have great importance in plant operations of industrial applications.