氟离子选择电极法测定低温铝电解质分子比

Determination of the molecular proportion of low-temperature aluminum electrolyte with fluoride ion selective electrode method

通过用氟离子选择电极法测定低温铝电解质中的氟离子浓度,然后用本文给出的分子比计算公式进行计算,结果经修正后得到低温铝电解质的分子比。对分子比的计算公式进行推导,并用推导的公式计算10个标准样品的分子比,求得分子比的修正系数λ=0.954 1。本法已用于KF-AlF3-Al2O3和KF-AlF3-Al2O3-NaF低温电解质分子比测定,测定结果与化学成分分析法(用火焰原子吸收光谱法测定样品中钾含量和蒸馏-硝酸钍滴定法测定氟的含量,再转换成氟化钾和氟化铝的量,根据分子比定义,计算出样品的分子比)测定结果基本一致,证明了该方法适用于新型的KF-AlF3-Al2O3-X低温电解质体系分子比的测定。

The concentration of fluoride ion of low-temperature aluminum electrolyte was determined by fluoride ion selective electrode method.Based on the computational formula of molecular proportion provided in this paper,the molecular proportion of low-temperature aluminum electrolyte was obtained after correction.The computational formula of molecular proportion was deduced and used for the calculation of molecular proportion of 10 standard samples.The obtained correction coefficient of molecular proportion was λ=0.954 1.This method has been applied to the determination of molecular proportion of KF-AlF3-Al2O3 and KF-AlF3-Al2O3-NaF low-temperature electrolytes.The results were consistent with those obtained by chemical analysis（The content of potassium was determined by flame atomic absorption spectrometry,and the content of fluorine was determined by distillation-thorium nitrate titrimetry.The content of potassium fluoride and aluminum fluoride were then obtained.Therefore,molecular proportion of sample could be calculated according to the definition）.It was proved that this method was applicable to the determination of molecular proportion of novel KF-AlF3-Al2O3-X low-temperature electrolyte system.