On-line preconcentration of silver on a sulfhydryl cotton microcolumn and determination by flow injection atomic absorption spectrometry
A rapid and sensitive on-line preconcentration method for the determination of silver in waters by flow injection flame atomic absorption spectrometry is described. Preconcentration is based on the retention of silver on a sulfhydryl cotton fibre microcolumn using a 0.05 mol l–1 HNO3 carrier solution and subsequent elution with 50 µl of 0.2 mol l–1 KCN. The preconcentration factor is 300 (50 µl elution volume) for a 15 ml sample volume. The detection limit under these conditions is 1 µg l–1 and the relative standard deviation is 3.5%(10 µg l–1 solution, n= 5).