Influence of SO42- on the structure of mixed nitrate salts
NI Haiou1, SUN Ze1, HUANG Long2, ZHOU Yang2, PANG Xvyan2, SONG Xingfu1, YU Jianguo1
1 National Engineering Research Center for Comprehensive Utilization of Salt Lake Resources, East China University of Science and Technology, Shanghai 200237, China; 2 Qinghai Salt Lake Industry Co. Ltd., Ge'ermu 816000, Qinghai, China
Abstract：Recent developments in energy technologies have led to an increased effort in scientific research into the use of nitrate salts as an energy storage material in recnet years. However, little is known about on the structure of molten salts and the influence of impurities on the structure of molten salt mixtures have been seldom reported. The presence of impurities can impose impacts on the thermophysical characteristics of molten salts that cannot be neglected. This study examines the addition of SO42- on the structure and hence properties of a mixed KNO3/NaNO3 salt with mass ratio of 1∶1 a Raman spectral meter and a X-ray diffractometer were used in the measurements under different temperatures. The results suggests that when the molten salt solidifies and crystallizes, SO42- ions combine with Na+ preferentially, and Na+ ions exist in the form of solid solution. It was also found that SO42- ions exist in the form of solid solution at the room temperature, and the structure of the mixed salts change significantly at 200 ℃ compared to that at room temperature, suggesting a solid-solid phase change during the heating procedure. The results also show that the state of solid solution of SO42- breaks at about 200 ℃.
倪海欧, 孙泽, 黄龙, 周扬, 庞旭岩, 宋兴福, 于建国. 杂质SO42-对混合硝酸盐结构影响分析[J]. 储能科学与技术, 2016, 5(2): 210-214.
NI Haiou, SUN Ze, HUANG Long, ZHOU Yang, PANG Xvyan, SONG Xingfu, YU Jianguo. Influence of SO42- on the structure of mixed nitrate salts. Energy Storage Science and Technology, 2016, 5(2): 210-214.
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2016, Vol. 5 
