离子交换微色谱柱对铬(Ⅵ)吸附行为的研究和分析应用

Study on the adsorption behavior of ion exchange chromatographic microcolumn to chromium(Ⅵ) and its analytical application

以分光光度法研究了阴离子交换树脂分离富集Cr（Ⅵ）的最佳条件,优化选择了上柱酸度和洗脱剂,即在pH 4.0 H2SO4介质条件下上柱,用20 g/L NaOH-90 g/L NaCl洗脱。对主要干扰元素铁、钒、钼的最大允许量进行了探讨。微型交换柱对Cr（Ⅵ）的富集倍数为33.3。Cr（Ⅵ）质量浓度在0-0.08μg/mL范围内服从比尔定律,相关系数为0.999 8,检出限为0.002 3μg/mL。方法用于测定含铬工业废水和标准溶液中的Cr（Ⅵ）,相对标准偏差为6.1%和2.1%,测定值与原子吸收光谱法的结果一致。

The optimal separation and enrichment conditions of Cr（Ⅵ） by anion exchange resin were studied using spectrophotometry.The column acidity and eluting agent were optimized： the column medium was H2SO4 at pH 4.0,and the eluting agent was 20 g/L NaOH-90 g/L NaCl.The maximum allowable limits of main interference elements（iron,vanadium and molybdenum） were investigated.The enrichment factor of micro exchange column to Cr（Ⅵ） was 33.3.Beer＇s law was obeyed for Cr（Ⅵ） in the range of 0-0.08 μg/mL.The correlation coefficient was 0.999 8,and the detection limit was 0.002 3 μg/mL.The proposed method was applied to the determination of Cr（Ⅵ） in industrial wastewater and standard solution.The relative standard deviations（RSD） were 6.1 % and 2.1 %,respectively.The determination results were consistent with those obtained by atomic absorption spectrometry.