Temperature and pressure effect on evaporation behavior of chloride salts using low pressure distillation

Abstract

The evaporation behavior of salt is helpful to determine the parameter for separating and purifying renewable materials from the waste salts. In the present work, low pressure distillation method was applied to investigate the evaporation behavior of chloride salts, namely LiCl, KCl, NaCl–KCl and LiCl–KCl, at different temperature and system pressure by a self-designed thermo-gravimetric furnace. The evaporation rate of the chloride molten salt was measured with the temperature range from 700 °C to 950 °C, and the ratios of the critical pressure to vapor pressure was deduced to 0.16 ± 0.04. The separation efficiency of fission products and corrosion product from chloride salts was further compared, and the results showed that the decontamination factors (DFs) of SrCl2, NdCl3 and CeCl3 in LiCl–KCl or NaCl–KCl, were around 103, while the DF values of CsCl and FeCl2 were almost 1.