摘要
在稀磷酸介质中,二氧化氯(ClO2)氧化I离子形成 I3配阴离子,I3进一步与结晶紫(CV)阳离子形成离子缔合物[CV][I3」。在聚乙烯醇存在下,该离子缔合物最大吸收波长λmax位于552 nm处,摩尔吸光系数ε=25 × 105L·mol-1·cm-1,对 ClO2的检出限为 0.6 μg/L,线性范围是 0.6~280μg/L。加入适量 KF溶液可消除自来水中Fe(Ⅲ)的干扰。方法对μg/L级ClO2 的测定有较好的选择性,可成功地用于自来水样品分析。
A highly sensitive spectrophotometric method has been developed for the determination of ClO2, based on the oxidation of I- to I-3(-) by ClO2 and the further reaction of I-3(-) with crystal violet to form the ion-association complex [CV] [I-3] in dilute phosphoric acid medium. The lambda(max) of the ion-association complex is 552 run (against reagent blank), the molar absorptivity is 2.5 x 10(5)L.mol(-1).cm(-1), the detection limit of ClO2 is 0.6 mug/L and the linearity range is 0.6 similar to 280 mug/L. The interference of Fe(III) is eliminated by adding potassium fluoride to the sample solution, so the determination method has good selectivity. ClO2 at mug/L levels in tap water has been determined by the method satisfactorily.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2002年第1期50-52,共3页
Chinese Journal of Analytical Chemistry