Physico-chemistry in distillation process
of (BiCl3-HCl-H2O) system
of (BiCl3-HCl-H2O) system
(1. School of Chemical Engineering, Zhejiang University of Technology,
Hangzhou 310014, China；
2. College of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China)
Hangzhou 310014, China；
2. College of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China)
Abstract: The gas-liquid equilibrium and evaporation behaviors of HCl and H2O in the distillation process of the BiCl3-HCl-H2O ternary system were investigated. With increasing content of BiCl3, the quasi-azeotropic point moves toward the low acidity and high temperature. The evaporation law of HCl and H2O in low-acidity BiCl3 solution was summarized. The residue phases were studied as well. The results show that the residue phases vary with the distillation temperature, namely BiCl3 and (BiCl3·xHCl) at low temperature and BiCl3 and BiOCl exist at higher temperature. The causes for the formation of different residue phases were discussed.
Key words: BiCl3; HCl; distillation; physico-chemistry