NbCl5-KCl二元系的熱力學(xué)性質(zhì)
(東北大學(xué) 理學(xué)院, 沈陽(yáng) 110004)
摘 要: 用高溫平衡-淬冷方法, 研究了NaCl-NbCl5和KCl-NbCl5二元系的熱力學(xué)性質(zhì)。結(jié)果表明： 在580～680 K和0.06～0.12 MPa范圍內(nèi), NaNbCl6(g)和KNbCl6(g)分別是惟一產(chǎn)物, 且NaNbCl6(g)比KNbCl6(g)穩(wěn)定。 反應(yīng)NbCl5(g)+NaCl(s)==NaNbCl6(g)的熱力學(xué)函數(shù)是ΔHm=(-28.3±1.5) kJ/mol和ΔSm=(-73.0±2.0)J/(mol·K)； 反應(yīng)NbCl5(g)+KCl(s)==KNbCl6(g)的熱力學(xué)函數(shù)是ΔHm=(-37.6±1.5)kJ/mol和ΔSm=(-93.7±2.0)J/(mol·K)。
關(guān)鍵字: NaNbCl6； KNbCl6； NbCl5； NaCl； KCl； 氣態(tài)配合物； 淬冷法
and NbCl5KCl binary systems
by quenching experiments
（School of Sciences, Northeastern University, Shenyang 110004, China）
Abstract: Thermodynamic properties of NaCl-NbCl5 and KCl-NbCl5 binary systems were studied by high temperature equilibrated quenching experiments. The results show that NaNbCl6(g) and KNbCl6(g) complexes are respectively their sole predominant vapour complexes roughly in the ranges of 580-680 K and 0.06-0.12 MPa, and that NaNbCl6(g) is more stable than KNbCl6(g). The thermodynamic properties are ΔHm=(-28.3±1.5) kJ/mol and ΔSm=(-73.0±2.0) J/(mol·K) for the reaction NbCl5 (g)+NaCl (s)==NaNbCl6 (g), and ΔHm=(-37.6±1.5) kJ/mol and ΔSm=-(93.7±2.0) J/(mol·K) for the reaction NbCl5 (g)+KCl (s)==KNbCl6 (g).
Key words: NaNbCl6； KNbCl6； NbCl5； NaCl； KCl； vapour complex； quenching method
