Cadmium in Water Samples determined by Atomic Absorption Spectrometry after Solid Phase Extraction using DOWEX 50WX2 resin

Abstract

The Pre-concentration of Cd(II) in water samples was carried out by using column solid phase extraction DOWEX 50WX2 prior to flame atomic absorption spectrometry analyzed. The analytical parameters consist of pH, flow rate, volume of eluent and volume of sample were determined.The optimum conditions were obtained pH was 5, sample flow rate was 1 mL min−1, volume of eluent nitric acid 1N was 10 mL and sample volume was 50 mL. The optimum conditions obtained were used to determine the detection limit and the accuracy of the method using tap water samples. Determination of detection limit used tap water which contain Cd 0.001 mg L-1 and the accuracy (recovery,%R) with concentration of Cd 0.01 mg L-1. The detection limit was found 0.2697±0.0899 µg L− 1 (n=7) and accuracy (n=7) was 93±6%. The result showed the accuracy still meets the acceptance criteria for accuracy (70%-125%) and the RSD 6% is smaller than the Horwitz value of 20.8%. Based on the accuracy (R%) and % RSD values obtained, it can be concluded that this method provides effective results for pre-concentration to increase the detection limit of Cd (II)in clean water using SSA-flame.