Solid Phase Extraction and Determination of Trace Amounts of Lead(II) Using Octadecyl Membrane Disks Modified by a New Schiff's Base and Flame Atomic Absorption Spectrometry

A highly selective, facile and reliable method for separation and preconcentration of the trace amounts of lead present in aqueous samples is introduced. By passing the solutions through an octadecyl silica membrane disk modified by a novel Schiff's base, Pb²⁺ ions are adsorbed quantitatively while almost all interfering ions pass through the disk. The retained lead(II) ions are then eluted from the disk surface by a minimal amount of organic eluents. The influences of pH, sample flow‐rates and interfering ions are also investigated. The proposed method permits an enrichment factor of about 500 or higher and a detection limit of 0.0065 ng mL^?;1.