摘要
利用碘离子选择电极,以0.1 mol/L KNO3-0.01 mol/L酒石酸为总离子强度调节剂、Na2SO3为还原保护剂,将加碘食盐中的IO3-还原为I-,在双液接饱和甘汞电极为参比电极的条件下,采用直接电位法和标准曲线法直接测定了溶液中的碘含量,实验结果表明,本方法线性范围10-1～10-7mol/L,检测下限4.6×10-8mol/L,样品具有较好的回收率(98.2%-100.7%),可以用此方法测定食盐中I-的含量。
This paper describes a rapid iodine content measure method by using the iodide ion selective electrode under a reducing buffer environment. With Na2SO3 as reducing agent and the buffer solution of 0.1 mol/L KNO^（3-）0.01moL/L tartaric acid, IO^（3-）is reduced to I^-. The iodide ion could be detected by the selective electrode with potentiometry. Then the detection result is compared with standard curved to determine the salt iodine content. The linear measurement interval is 10^（-1）～ 10^（-7） mol/L with the minimum detects concentration of 4.6 × 10^（-8）mol/L. The recovery coefficient is 98.2% - 100.7%.
出处
《环境与发展》
2011年第12期157-160,共4页
Environment & Development
关键词
碘离子选择电极
快速测定
食盐
iodine
ion selective electrode
rapid determination
