利用新的催化反应极谱法测定痕量铁

Determination of Trace Iron(Ⅲ)by a New CatalyticReaction-Polarographic Method

基于在酸性条件下，铁对溴酸钾氧化酸性铬蓝Ｋ反应的催化作用，利用极谱仪器作为监测手段，测定酸性铬蓝Ｋ在０．０８ｍｏｌ／ＬＮＨ３Ｈ２Ｏ～０．０１ｍｏｌ／Ｌ（ＮＨ４）２ＳＯ４介质中的极谱波，建立了催化动力学极谱法测定痕量铁的新方法．方法的线性范围为１０～１００ｎｇ／ｍＬ，检出限为０．１５ｎｇ／ｍＬ，应用于天然水及食品中铁的测定，结果满意．

Iron(Ⅲ) can be determined with a new and sensitive method by polarography,based on the catalytic effect of iron(Ⅲ) on the oxidation of acid chromeblue K in the presence of potassium bromate at sulfuric acid and 100℃,the reaction rate was monitored by measuring the polarographic peak current of the acid chrome blue K. Iron(Ⅲ)concentration of 10～100ng/mL can be determined by the fixed time method,and the limit of detection was 0.15ng/mL.The method was used to determine iron concentration in natural water and food with satisfactory results..