Solid Phase Extraction of Ultra Traces Copper (II) using Octadecyl Silica Membrane Disks Modified by a New Schiff Base Prior to Determination by Flame Atomic Absorption

A simple, reliable and rapid method for pre-concentration and determination of copper using octadecyl silica membrane disk modified by a recently synthesized Schiff base (N, Nbis(2-hydroxy-4-methoxybenzaldehyde)-2,6-diaminopyridine) and flame atomic absorption spectrometry is presented. Various parameters including pH of sample solution, flow rates, the amount of ligand and type of stripping reagent were optimized. Under optimum experimental conditions, the breakthrough volume is greater than 2000 ml with an enrichment factor of more than 400 and detection limit of 5.4 ng.L-1. The capacity of the membrane disks modified by 5 mg of the ligand was found to be 552.53 mu g of copper. The effects of various cationic interferences on percent recovery of copper ion were studied. The method was successfully applied for the determination of copper ion in different water samples.