Dissolution of Niobium Pentachloride in Chloride Melts

The dissolution of niobium pentachloride in molten alkali chlorides was studied in NaCl-KCl-, NaCl-CsCl-and LiCl-KCl-based melts and the progress of the dissolution was followed by in situ spectroscopy measurements. In most instances the spectra contained only the low energy edge of the charge transfer band. The oxidation state of niobium in quenched melt samples of the obtained electrolytes was close to 5.0 (Table 4.4.1). This result is in a good agreement with the literature data [2-6] and indicates that NbClg species constituted the main product of this reaction. 

However, at relatively high niobium concentrations in the melt NbClg partly decomposed, yielding NbCls and chlorine gas  

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