RECOVERY OF RARE METALS WITH A NEW ORGANOPHOSPHORUS EXTRACTANT

This work studies a new organophosphorus extractant, DS5834, developed by Zeneca Specialties, which has been shown to be efficient for removing metal ion impurities. The new reagent is a formulation of a type similar to M2EHPA, a monoester, diacid phosphate extractant, but with a lower reported water solubility. A preliminary study was undertaken to determine if DS5834 is effective for the recovery of gallium, indium, and germanium,and the separation of samarium and gadolinium from acid solutions by solvent extraction. The results showed that DS5834 is a strong extractant for all of the metals studied except germanium, which was not extracted, It is not selective for the rare earth elements samarium and gadolinium, and consequently is not effective for the separation of these metals. Iron is also extracted by this reagent but with a lower distribution factor.