氯化物熔体中Lu合金形成的研究

STUDY ON FORMATION OF LUTETIUM ALLOYS IN CHLORIDE MELT

研究了在ＮａＣｌ—ＫＣｌ—ＬｕＣｌ，熔体中Ｌｕ（Ⅲ）在Ｃｕ，Ｃｏ，Ｎｉ和Ｆｅ电极上还原的电极过程测定了Ｌｕ（Ⅲ）在Ｃｕ，Ｃｏ，Ｎｉ和Ｆｅ四种电极上的循环伏安曲线，确定Ｌｕ（Ⅲ）在这些电极上还原先形成合金，电位足够负时生成金属Ｌｕ验证了合金的数目，计算出Ｌｕ（Ⅲ）在８００℃，ＮａＣｌ—ＫＣｌ—ＬｕＣｌ，熔体中Ｃｕ，Ｃｏ，Ｎｉ和Ｆｅ电极上生成的金属间化合物的生成自由能Ｌｕ原子在Ｌｕ＿２Ｃｏ＿（１７）合金相内的扩散系数与温度的关系式为ｌｎＤ＝－５５．７×１０￣３／ＲＴ－１６．３，扩散活化能为５５．７ｋＪ／ｍｏｌ。

The formation of lutetium alloys on the Cu. Co. Ni and Fe cathodes in NaCl-KCl-LuCl_3 melt has been investigated. The cyclic voltammograms of Lu(Ⅲ) on Cu.Co, coefficient of Lu(Ⅲ) are measured. Potentail-time curves have been made to testify the number of alloys and to calculate the free energy of formation of the lutetium alloy on the Cu.Co, Ni and Fe electrodes in NaCl-KCl-LuCl_3 melt at 800℃ . The relationship between diffusion coefficient and temperature of Lu atom in Lu_2Co_(17) alloy phase which is determined by means of current-time curves can be expressed as In D=-55.7 × 10￣3/RT-16.3, the diffusion activation energy is 55.7 kJ/mol. Correspondent: LIU Guankun, professor, Department of Chemistry, Zhongshan University,Guangzhou 510275