四氟硼酸盐样品经乙醇(1+1)溶液溶解,采用氟离子选择电极测定其中游离的氟离子含量。试验表明:氟离子选择性电极对氟具有良好的选择性和电位响应特性。在pH 5.8~6.0的介质中,25 ℃恒温条件下,电极电位呈现能斯特响应,线性范围为0.5~10 μg·L-1,斜率为61.453 mV·pc-1。将该电极用于3种四氟硼酸盐的分析,测得方法的回收率在96.7%~104%之间,相对标准偏差(n=6)在0.8%~4.2%之间。

Sample of tetrafluoroborate was dissolved with ethanol (50+50) solution, and content of F- in the sample solution was determined with fluoride ion selective electrode. It was found that excellent selectivity and good potential response toward F- were achieved by the ion selective electrode, which showed Nernst potential response in the range of 0.5 to 10 μg·L-1 with slop of 61.453 mV·pc-1 in a medium of pH 5.8-6.0 at 25 ℃. Recovery was tested by standard addition method on the base of 3 samples of tetrafluoroborate, results of recovery found were in the range of 96.7%-104% with RSD′s (n=6) in the range of 0.8%-4.2%.