离子色谱法测定石墨及其制品中的F~-和SO_4~(2-)

建立了离子色谱法测定石墨及其制品中F~-和SO_4~(2-)的检验方法。用乙酸钠灼烧样品,水微沸提取,过滤定容,过滤膜后用离子色谱对溶液中的F~-和SO_4~(2-)含量进行测定。选用3.6 mmol/L Na_2CO_3溶液为淋洗液,流量为0.7 mL/min,渗析时间为8 min,转移时间为30 s。F~-和SO_4~(2-)平均加标回收率分别为92.4%,105.2%;测定结果的相对标准偏差分别为1.42%,3.89%(n=8)。该方法稳定,操作简便,准确度高,分析速度快,适用于石墨及其制品中F~-及SO_4~(2-)的测定。

Determination of F- and SO42- in Graphite and Its Products by Ion Chromatography

Ion chromatography method was established for the determination of F– and SO42– in graphite and its products. The sample was melted with sodium acetate, and extracted by micro boiling water, F– and SO42– was determinated in solution by ion chromatography after filtration. 3.6 mmol/L Na2CO3 solution was used as the leachaeate with the current flow of 0.7 mL/min. The dialysis time was 8 min, and transfer time was 30 s. The average standard recovery rate of F– and SO42– was 92.4%, 105.2% with the relative standard deviation of 1.42%, 3.89%(n=8), repectively. The method is stable, easy to operate, has high accuracy and fast analysis speed, and it is suitable for the determination of F– and SO42– in graphite and its products.