Solubility of CaS in Molten CaCl2

Abstract
In order to check the solubility of CaS during sulfide reduction in molten CaCl2, the mixture of CaCl2 and a small amount of CaS was melted in Ar at the range from 1123 K to 1223 K. The melt was sampled by quartz tube and rapidly solidified. The solidified samples showed a lamella structure with CaS particles, which results in a simple eutectic reaction between CaCl2 and CaS. Using ICP-AES analysis, the saturation of CaS was found to be completed within 1.8 ks, and 1.77 +/- 0.1 mol% CaS at 1173 K was measured as the solubility limit at the initial composition of 3.0 mol% CaS. A tentative phase diagram of CaCl2-CaS binary system was proposed based on the solubility analysis in these temperatures and eutectic structure.