Formation of strontium and barium phosphates in chloride melts

A. B. Ivanov, E. D. Byzova, V. A. Volkovich, A. V. Chukin. 

ABSTRACT

      Processes taking place during the reaction of solutions of barium and strontium phosphates with sodium orthophosphate were studied in melts based on LiCl–KCl eutectic (550^oC), NaCl–KCl–CsCl eutectic (650^oC), NaCl–KCl equimolar mixture (750^oC), as well as in NaCl–KCl–CsCl–LaCl₃ melt (650^oC) in an inert atmosphere. Chemical and X-ray diffraction analyses were used to determine composition of the sparingly soluble phosphates formed. The effect of the molar ratio of phosphate-ions to Sr²⁺/Ba²⁺ on the phase composition of the precipitated phosphates was studied. The conditions required for quantitative precipitation of strontium and barium from the melt in the form of phosphates were determined.

KEY WORDS:

barium, strontium, lanthanum, chloride melts, phosphates, precipitation, spent nuclear fuel.

DOI: 10.31857/S0235010621030075