对LiF-NdF3系统进行实验性确定和热力学优化
ChunFa Liao1,2, ZanHui Fu1,2, LiangHua Que1,2
1Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology Ganzhou 341000 China sci_rech@163.com.
RSC advances
|August 14, 2023
概括
本研究详细介绍了LiF-NdF3相图,这对于通过电解高效生产新至关重要. 精确的相位图优化了盐的选择,提高了电解效率并降低了成本.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是一种金工业.
- 物理化学 物理化学
背景情况:
- 的生产依赖于化盐的电解,主要使用LiF-NdF3-Nd2O3系统.
- LiF-NdF3 双相图对于优化电解过程至关重要.
- 精确的相位图数据有助于选择合适的盐成分,提高生产效率.
研究的目的:
- 通过实验确定LiF-NdF3二进制系统的液体和固体温度.
- 为LiF-NdF3系统构建一个准确的相位图.
- 使用FactSage软件为LiF-NdF3系统开发一个热力学数据库.
主要方法:
- 差分扫描热量计 (DSC) 用于测量液体和固体温度.
- 对于二进制系统,使用次常规解决方案模型进行了热力学优化.
- 使用FactSage软件开发了LiF-NdF3.3的新数据库.
主要成果:
- 在68.4%的LiF-31.6%的NdF3和731.5°C的Eutectic点被确定.
- 确定了过多的吉布斯自由能量的二进制相互作用系数:0L = -39966 + 17.68T,1L = -7667 + 26.1T,2L = -6000.
- 工业级 NdF3 和含有 Nd2O3.3 的 NdF3 的液体温度较高.
结论:
- 建立了一个精确的LiF-NdF3相图,这对于优化电解至关重要.
- 开发的热力学数据库将有助于过程设计和降低成本.
- 像Nd2O3这样的杂质的存在显著影响液体温度,需要仔细选择原料.
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