酸性媒染紫-示波计时电位法测定天然水和饮用水中铝

Determination of Aluminum in Natural Waters and Drinking Waters by Alternating Current Oscillopolarography Using Solochrome Violet RS

报道酸性媒染紫（ＳＶＲＳ）－示波计时电位法测定天然水及饮用水中铝。在０．８５ｍｏｌ／Ｌ ＮＨ３·Ｈ２Ｏ－ＮＨ４Ｃｌ－５×１０－５ｍｏｌ／Ｌ ＳＶＢＳ（ｐＨ８．８）底液中，Ａｌ－ＳＶＲＳ络合物在－１．０５Ｖ电位处产生灵敏切口，切口深度与铝浓度成正比，可用于定量分析。线性范围为１×１０－７～６×１０－６ｍｏｌ／Ｌ． ＲＳＤ为５．５％ （ｎ＝１０，２×１０－７ｍｏｌ／Ｌ），检测限为５×１０－８ｍｏｌ／Ｌ。本法特点为：在碱性条件下，无需加热，无需通氮除氧，无需预富集，大大减少了分析时间。仪器简单，方法灵敏准确，特别适用于天然水和饮料中Ａｌ的分析。对实际水样进行了分析，与ＩＣＰ／ＡＥＳ法所测结果基本一致。

A simple and reliable electroanalytical method for the fast determination of aluminum in natural and drinking waters by a. c. oscillopolarography using solochrome violet RS(SVRS) is described. The alkaline buffer solution used was 0.85 mol/L NH3.H2O-NH4Cl (pH 8.8) containing 5 x 10(-5) mol/L SVRS. A sensitive incision due to the redox reaction of Al-SVRS complex adsorption wave on the Hg-film electrode was observed on the dE/dtE oscillogram at -1.05 V. The incision depth was linearly proportional to the Al concentration in the range of 1 x 10(-7) similar to 6 x 10(-6) mol/L. No serious interference was found. The detection limit of this method was 5 x 10(-8) mol/L, and the relative standard deviation was 5.5% for 2 x 10(-7) mol/L Al (n = 10). This method was successfully applied to the determination Al in 22 real samples. The results were found to be in good agreement with those obtained fry inductively coupled plasma-atomic emission spectrometry.