Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 17 No. 2 April 2007|
（1. School of Sciences, Northeastern University, Shenyang 110004, China;
2. School of Sciences, Shenyang University of Technology, Shenyang 110023, China）
Abstract:Thermodynamic studies were carried out for the vapor complex of sodium chloride with zirconium tetrachloride at 718−778 K and 0.5−2.5 kPa by using high temperature phase equilibrium-quenching experiments, taking closed Pyrex glass ampoules as the reaction containers. The results show that the sole predominant vapor complex is Na2ZrCl6 for the ZrCl4-NaCl system under the experimental conditions. The thermodynamic equilibrium constants and other thermodynamic functions of the reaction 2NaCl(s)+ZrCl4(g)=Na2ZrCl6(g) have been derived from the measurements. The results for the changes in enthalpy and entropy are ∆H0=(−70.1±1.5) kJ/mol and ∆S0=(−105.9±2.0) J/(mol∙K) in the temperature range.
Key words: ZrCl4; NaCl; Na2ZrCl6; vapor complex; phase equilibrium-quenching experiment