Reprocessing cruds: zirconium (IV) contribution to their formation dibutylphosphoric acid demixion induced by zirconium (IV) in nitric acid solutions. Solubility of zirconium (IV) in HDBP

The low Zr(IV) compounds solubility with the most important degradation products of tributylphosphate (TBP), the PUREX process extractant (dibutylphosphoric acid (HDBP) and monobutylphosphoric acid (H2MBP)), can strongly disturb the implementation of the process (clogging or third phases formation). CEA studied systematically the formation and the properties of these compounds: 31P nuclear magnetic resonance spectroscopy allowed to understand the original Zr(IV) property that induces demixions of HDBP from aqueous nitric solutions. The temperature variation and the spectra simulation induce that Zr(IV) is very soluble in pure HDBP (more than 1M). Zr(IV) in HDBP solutions can also be prepared by dissolving Zr(DBP)2(NO3)2 in HDBP. 4 figs., 4 refs