二元混合硝酸盐的配制及性能

PREPARATION AND EXPERIMENTAL STUDY OF BINARY NITRATE SALTS

按照不同配比、不同配制方法得到系列二元混合硝酸盐样品,并得到不同混合熔盐的差式扫描量热曲线,同时对配制的熔盐进行多次反复熔化和加热,研究其稳定性。结果表明:当硝酸钠占混合物总质量的40%～60%,或硝酸钠和硝酸钾的质量比为9∶1时,形成的混合物具备共晶性质,其他比例的混合熔盐无法达到共晶状态;两种配制方法均可达到共晶状态,其熔点十分接近;而且,配制的混合熔盐经过反复加热后,其熔点和分解点变化不大,证明对于二元混合熔盐可仅通过物理搅拌即可达到共晶状态。

Nine kinds of binary nitrate salts with different ratio of KNO3 and NaNO3 were prepared and the DSC （Differential Scanning Calorimetry） curves were obtained by using STA409-PC manufactured by Netschi company from Germany. The measured results showed that the binary nitrate salts with the ratio of KNO3 and NaNO3 in 4： 6, 6： 4, 5：5 and 9：1 have eutectic and others have no eutectic. Then two prepared methods were used to prepare the binary nitrate salts. The DSC curves and TG curves of prepared molten salts were obtained and analyzed. The re- suits showed that these two methods are both valid in making up eutectic mixed nitrate. The melting points of the binary nitrate salts prepared by the two methods are very close, In addition, there is no big change about its melting point and decomposition point after nitrate molten salts are heated repeatly. A simple method of binary nitrate salts preparation at large scale was proved to be valid by the experiments.