The Formation of a Third Phase in Ytterbium Extraction Chromatography Columns with HDEHP

In connection with the task of separating Lu-177 from Yb macroquantities, the formation of gel-like salts ( "third phase "), which significantly reduces the efficiency of chromatography in the recovery of REE carrier-free radionuclides, was studied. The formation of polymeric gel-like salts of ytterbium di(2-ethylhexyl)phosphate ( "third phase ") under dynamic conditions in the Yb(NO3)(3)-HNO3-HDEHP system (sorbent LN Resin) was demonstrated using Fourier IR spectroscopy. The experiment consisted of a layer-by-layer analysis of the sorbent; the spectra of the samples were compared with the spectra of a specially prepared reference salt sample.