Solid phase extraction and determination of ultra trace amounts of copper using activated carbon modified by N,N '-bis(salicylidene)-1,2-phenylenediamine

N,N'-bis(salicylidene)-1,2-phenylenediamine(salophen) modified activated carbon was prepared and used as an effective sorbent for solid phase extraction of Cu(II) ions from aqueous solutions. The salophen modified activated carbon showed a high sorption affinity for Cu(II). In this method a column mode was used for preconcentration of copper(II) in the pH range 3.5-6.5. The retained copper was eluted with 0.1 mol l(-1) EDTA and determined by atomic absorption spectrometry. The calibration graph was linear over the copper concentration in the range 0.05-1.5 mu g ml(-1). Five replicate determination of 0.4 mu g ml(-1) of copper(II) gave a mean absorbance of 0.385 with a relative standard deviation of 1.35%. The detection limit was 0.0133 mu g ml(-1). The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for determination of copper in various real samples.