Affiliation:
1. Institute of High-Temperature Electrochemistry, Ural Branch of the RAS
Abstract
Based on our experimental data and those obtained by researchers, mainly employees of our Institute (IHTE UB RAS), the regularities of changes in the composition of saturated vapors and the volatility of components of molten mixtures of tetrachlorides of uranium and some other metals (ThCl4, HfCl4, ZrCl4, TiCl4) with alkali metal chlorides depending on the temperature, concentration and cationic composition of melts are discussed. It is noted that the dissolution of UCl4 as well as other tetrachlorides in molten alkali metal chlorides is accompanied by complexation, manifested in a sharp decrease in the volatility of the corresponding tetravalent metal chloride and its content in saturated vapors. The strength of the complex chloride anions of polyvalent metals formed in melts increases significantly with a decrease in their concentration, replacement of the solvent salt in the series from LiCl to CsCl and temperature. As a result, the volatility values of UCl4, ThCl4, HfCl4, ZrCl4, TiCl4 and the composition of vapors above their solutions in ionic melts vary greatly. At the same time, according to the experimental data hafnium, zirconium and titanium tetrachlorides (especially TiCl4), which are much more volatile in the individual state, have higher volatility and content in saturated vapors over solutions in molten alkali metal chlorides.
Publisher
The Russian Academy of Sciences
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