甲基红氧化褪色光度法测定食盐中碘

Photometric determination of iodide in edible salt by oxidation-decoloration of methyl red

基于在盐酸介质中 ,碘酸根在溴化钾的催化作用下使甲基红氧化褪色的反应 ,建立了测定微量碘的新方法。方法的线性范围为 8μg/2 5mL～ 2 2 μg/2 5mL ,表观摩尔吸收系数为 6 .5× 1 0 4 L·mol- 1 ·cm- 1 ,已用于食盐中碘的测定。

A new method of determination of micro amounts of iodine in edible salt was reported. The method was besed on oxidation-decoloration of methyl red with iodate in a HCl medium with KBr as the catalyst. A linear relationship was established at 8～22 μg/25 mL for iodide with a molar absorptivity of 6.5×10 4 L·mol -1 ·cm -1 .