2-(2-喹啉偶氮)-1,3-二羟基苯固相萃取分光光度法测定环境样品中钒的研究

Study on solid phase extraction and spectrophotometric determination of vanadium in environmental samples with 2-(2-Quinolinylazo)-1,3-dihydroxidebenzene

根据新试剂 2 (2 喹啉偶氮 ) 1,3 二羟基苯 (QADHB)与钒的显色反应及C1 8固相萃取小柱对显色络合物的固相萃取 ,建立了一种测定环境样品中痕量钒的新方法 ,在pH 3 5的柠檬酸 -氢氧化钠缓冲介质中 ,溴化十六烷基三甲基铵 (CTMAB)存在下 ,QADHB与钒反应生成 2∶1稳定络合物 ,该络合物可用C1 8固相萃取小柱富集 ,小柱上富集的络合物用乙醇 (内含 2 %乙酸 )洗脱后用分光光度法测定 ,在富集后的测定液中 ,络合物最大吸收波长为 5 5 2nm ,摩尔吸光系数ε=8 2 9ⅹ 10 4 L·moL- 1 ·cm- 1 ,钒含量在 0～ 1 0 μg ml内符合比尔定律。方法用于几种环境样品中钒的分析 。

Based on the color reaction of 2-(2-quinolinylazo)-1,3-dihydroxidebenzene (QADHB) with vanadium(v) and the solid phase extraction of its colored complex with C 18 cartridge, a new method for the determination of vanadium was studied. In the presence of CTMAB and citric acid-sodium hydroxide buffer solution (pH 3.5) medium. QADHB reacts with vanadium(II) to form a stable 2∶1 complex. The colored complex was extracted by C 18 cartridge and eluted the retained chelate from cartridge with ethanol (containing 2% of acetic acid), then can be determined by spectrophotometry at 552 nm. Beer's law is obeyed in range of 0～1.0 mg/l. This method can be applied to the determination of vanadium in environmental samples with good results.