The contents of fluoride and chloride in lead dust were determined by ion selective electrode method with pH/conductivity/comprehensive ion testing instrument. The lead dust was dissolved in mixed solution of hydrogen peroxide, citric acid and nitric acid. The interference of sulfur ions in the determination of chloride ion could be eliminated by the nitric acid and hydrogen peroxide. The interference of iron and aluminum in lead dust in the determination of fluoride ion could be eliminated by adjusting the total ionic strength of citric acid and fluoride in buffer solution. The results showed that, the relative standard deviations (RSD, n = 6) of F- and Cl- were less than 2.5% and 2. 4%, respectively. The coexisting ions in lead dust had no interference with the determination of F" and Cl . The proposed method was applied to the simultaneous determination of fluoride and chloride in lead dust with good feasibility and practicability.%提出了一种使用pH/电导率/离子综合测试仪检测电铅灰中氟和氯含量的离子选择电极方法.电铅灰试样用过氧化氢、柠檬酸和硝酸的混合酸溶解,硝酸与过氧化氢可以消除硫离子对氯离子测定的干扰,柠檬酸与氟总离子强度调节缓冲溶液可以消除电铅灰中铁、铝对氟离子测定的干扰.样品测试结果显示,方法的相对标准偏差(n=6)为:氟离子≤2.5％,氯离子≤2.4％.电铅灰中共存离子对氟离子和氯离子的测定无干扰.该方法用于电铅灰中氟和氯的同时测定,具有很好的可行性和实用性.
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