NdF3—NaF—LiF系初晶温度的研究

我国现行稀土氟盐电解采用ＬｉＦ作添加剂，电解操作困难，电解成本高。采用廉价的ＮａＦ或其它碱金属氟化物替代或部分替代ＬｉＦ，是稀土电解的一个研究方向。本文测定ＮｄＦ３－ＮａＦ熔体对Ｎｄ２Ｏ３的溶解能力，采用二因子三次正交回归设计研究了ＮｄＦ３－ＮａＦ－ＬｉＦ系的初晶温度，得出该体系初晶温度回归方程的数学模型，分析了ＮａＦ、ＬｉＦ对初晶温度的影响。研究结果表明，从降低熔体初晶温度和提高熔体对Ｎｄ２Ｏ３溶解能力的角度出发，ＮａＦ替代或部分替代ＬｉＦ作为氟盐体系电解金属钕的支持电解质是可行的。

INTTIAL CRYSTALLIZATION TEMPERATURE OF NdF_3 NaF LiF SYSTEM

In order to make the electrolyzing much easier and reduce the cost of molten salt electrolysis with rare earth fluoride system, NaF or other alkali fluorides are supposed to replace LiF currently used in RE electrolysis as additive. On the basis of measuring the solvability of Nd 2O 3 in NdF 3 NaF melts, the initial crystallization temperature (ICT) of NdF 3 NaF LiF system is studied by using two factor three power orthogonal regression design. The mathematical model of regression equation about ICT of the system is presented. The effects of NaF and LiF on the initial crystallization temperature are discussed. From the point of view to lower ICT and increase the solvability of Nd 2O 3 in neodymium fluoride melts, it is feasible to replace LiF completely or partly with NaF as co electrolyte in neodymium electrolysis.