Column solid phase extraction of copper and nickel on triethylenetetramine bonded silica gel for their atomic absorption spectrometric determination

A procedure for the preconcentration of Cu(II) and Ni(II) is proposed using a minicolumn filled with silica gel modified by triethylenetetramine. The retained analytes on the modified silica gel were eluted with hydrochloric acid solution. The metal ions in the eluate were determined by flame atomic absorption spectrometry. The effect of various factors, such as pH of the sample solution, sample volume, flow rate of the sample solution, type of eluent, and matrix content of the sample solution, on preconcentration were examined to obtain optimum conditions. The recoveries for Cu(II) and Ni(II) ions under optimum preconcentration conditions were 98.3 +/- 1.3 and 99.2 +/- 1.4% at 95% confidence level, respectively. The analytical detection limits of Ni and Cu were found to be 0.22 and 0.36 mu g L-1, respectively. The proposed method was applied to the determination copper and nickel in river and synthetic sea water.