Solid-phase Chelate Extractive Preconcentration of Heavy Metal Ions Prior to Their Ultratrace Determination by Microsample Injection System Coupled Flame Atomic Absorption Spectrometry

摘要

A Chromosorb-105 resin/1-(2-pyridylazo)-2-naphthol (PAN) system was developed for solid phase chelate extractive preconcentration of heavy metal ions. The metal ions on Chromosorb-105 resin column were eluted with 3.0 mL of 2.0 mol L~(-1) HNO3 and determined by microsample injection system coupled flame atomic spectrometry (MIS-FAAS) using 75.0 uL of sample solution for single element determination. The influence of pH, resin amount, reagent amount, flow rate and volume of eluent and sample solution was optimized. The quantitative recoveries (>95%) of Fe(III), Zn(II), Cu(II) and Pb(II) ions were achieved at pH 9; resin amount, 700 mg; reagent amount, 6.0 μmol; flow rate of eluent and sample solution, 1.0 mL rnin~(-1) and 5.0 mL min~(-1), respectively. The limit of detection and limit of quantification of understudied analytes were found to be 0.17-1.74 μg L~(-1) and 0.40-2.98 μg L~(-1), respectively with preconcentration factor of 150-300. The proposed method was validated by analysis of waste water (BCR-715) as a certified reference material. The method was applied successfully for ultratrace determination of studied metal ions in tap water and hot spring water samples.