负催化光度法测定微量铁──Fe（Ⅲ）──H_2O_2──甲基紫体系

DETERMINATION OF MICRO-IRON BY NEGATIVE CATALYTIC SPECTROMETRY Fe(Ⅲ)-H_2O_2-METHYL PURPLE SYSTEM

提出了一种褪色光度法测定Ｆｅ３＋的新方法．即在Ｆｅ３＋的催化作用下，Ｈ２Ｏ２在稀Ｈ２ＳＯ２的酸性环境中氧化甲基紫使其褪色．Ｆｅ３＋线性范围０～６μｇ／２５ｍＬ，本法选择性好，用于地面水和地下水的测定，结果满意．

A new method was developed for the determination of Fe3+ using decolorization spectrometry. At the catalysis of Fe3+,methyl purple was oxidized and decolorized by H2O2 The linear range of Fe3+ is 01～6μg/25ml. The molecular light extinction coefficient is 2. 52× 105. This method has good selectivity. Good results were obtained for the determination of iron in ground and underground water.