三元硝酸熔盐体系的相图研究

Phase Diagram Calculation of Ternary Molten Nitrate Salts

利用了“硬球”离子相互作用模型和共形离子溶液模型进行三元相图计算,完成了LiNO_(3)-KNO_(3)-Ca(NO_(3))_(2)三元硝酸熔盐的相图计算。计算结果表明这个三元体系的共熔点为380.98 K,此时LiNO_(3),KNO_(3),Ca(NO_(3))_(2)的摩尔组成分别为0.259,0.597,0.144。相图计算结果与实验值相比,共熔点相近,组成上有一些偏差。因此,相图计算在一定程度上可预测多元熔盐体系共熔点及共熔点处体系组成和减轻多元相图研究工作的繁重任务。

The design of LiNO_(3)-KNO_(3)-Ca(NO_(3))_(2) ternary nitrate molten salt was completed by using the ion“hard sphere”model and the common ion solution model.The calculation results showed that the eutectic point of this quaternary system was 380.98 K,and the molar composition was 0.259 LiNO_(3),0.597 KNO_(3) and 0.144 Ca(NO_(3))_(2).Calculated melting point of this mixture was in good agreement with the experimental values,but the deviation of calculated and experimental values of the eutectic composition was close.Therefore,the phase diagram calculation could predict the eutectic point and the composition of the multiple molten salt systems.That could reduce the onerous task of the research on the multiple phase diagram.