催化动力学分光光度法测定区域地球化学样品中的碘

Determination of Iodine in Regional Geochemical Samples by Kinetic Spectrophotometry

试样用碳酸钠-氧化锌混合熔剂半熔,水提取,乙酸中和,乙酸和乙酸钠形成的缓冲体系控制酸度,利用碘离子在与4,4’-四甲基二氨基苯甲烷和氯胺T的氧化反应中的催化作用,能生成不稳定的蓝色配合物,其吸光度值与碘离子含量成正比,以此来测定区域地球化学样品中碘的含量,根据此法测定的结果准确度、精密度高,检出限低,适用于区域地球化学样品中碘的测定。

The sample was half melted with sodium carbonate-zinc oxide mixed flux,extracted by water and neutralized by acetic acid and the acidity of system was controlled by buffer solution system generated by acetic acid and sodium acetate. The catalytic action of iodide ions in the oxidation reaction of chloramines and 4,4 '-tetramethylenediamine can generate an unstable blue complex. The absorbance value was proportional to the content of iodide ions. Based on this,the iodine in regional geochemical samples was measured. The measuring method was widely used with high accuracy,precision and low detection limit in regional geochemical samples.