EXTRACTION OF STRONTIUM FROM ACIDIC NITRATE MEDIA USING A MODIFIED PUREX SOLVENT

A new process for the extraction and recovery of strontium from acidic waste streams is described. In this process, a modification of the previously described SREX (for strontium extraction) process, strontium is extracted from acidic (greater than or equal to 2 M nitric acid) solution using a 0.2 M solution of di-t-butylcyclohexano-18-crown-6 in any of a variety of phase modifier/paraffinic hydrocarbon mixtures, among them a PUREX-like diluent comprised of a 1.2 M solution of tri-n-butyl-phosphate in Isopar L. Tests of this process solvent on a synthetic dissolved sludge waste show that only strontium and barium are appreciably extracted by the crown ether under the experimental conditions. As expected, uranium and plutonium are extracted even in the absence of the crown ether.