【摘要】 建立了在超声波作用下,HAc-NaAc缓冲溶液和邻二氮菲选择性溶解分光光度法直接测定碳酸盐相中微量亚铁的方法。结果表明,在适宜条件下,含2 g/L邻二氮菲的HAc-NaAc缓冲溶液(pH3)可选择性溶解并络合碳酸盐相中的Fe(Ⅱ),通过加入EDTA溶液有效地抑制了Fe(Ⅲ)的光还原作用。常见含铁矿物如赤铁矿、磁铁矿及硅酸盐等均对碳酸盐中Fe(Ⅱ)的测定无干扰。样品经30%的H2O2浸泡、过滤、晾干预处理,能有效地消除黄铁矿和有机物的干扰。方法用于石灰岩国家一级标准物质的测定,结果与标准值相符。更多还原

【Abstract】 A method for the determination of trace Fe(Ⅱ) in carbonate phase by spectrophotometry with 1,10-phenanthroline as complexant was reported in this paper.The sample was selectively dissolved in HAc-NaAc(pH=3.0) buffer solution under ultrasonic condition and the chromatogenic reaction occurred from the complexation of released ferrous ions with 1,10-phenanthroline in the present of EDTA which effectively restrain the photoreduction effect of Fe(Ⅲ).The results from the experiments show that some common ferrous minerals such as hematite,magnetite and silicate have no interference on the determination of Fe(Ⅱ) from carbonate phase and the interference from pyrite and organic compounds can be effectively eliminated by sample pretreatment including samplesoaking with 30% H2O2,filtration and drying.The method has been applied to the determination of trace Fe(Ⅱ) in National Standard Reference limestone samples and the results are in agreement with certified values.更多还原