Analytical Sciences

Abstract − Analytical Sciences, 15(3), 269 (1999).

Electrothermal Atomic Absorption SpectrometricDetermination of Copper(II) Using a Tungsten Metal Furnace afterPreconcentration onto Chitosan
Hiroaki MINAMISAWA*, NobumasaARAI* and Tadao OKUTANI**
*Department of Liberal Arts and Basic Science, College of IndustrialTechnology, Nihon University, Shinei, Narashino, Chiba 275-8576, Japan
**Department of Industrial Chemistry, College of Science andTechnology, Nihon University, Kanda-Surugadai, Chiyoda, Tokyo 101-0062,Japan
The properties of chitosan to adsorb metal ions andto dissolve in some organic acids were applied to the preconcentration anddetermination of copper(II) in water samples by tungsten metal furnaceatomic absorption spectrometry. Copper(II) was quantitatively adsorbed ontochitosan over the pH range of 5.0 - 9.0. The chitosan adsorbed copper(II)was separated from the sample solution by a membrane filter, then dissolvedin 2.0 cm3 of 0.1 mol dm-3 acetic acid. An aliquot ofthis resulting solution was introduced directly into a tungsten metalfurnace, and the absorbance of copper was measured by atomic absorptionspectrometry. An ashing temperature of 900 and an atomizing temperature of2500 were selected, respectively. The detection limit for copper(II) was 0.002 mg dm-3 (S/N > =3). A quantitativerecovery was obtained over the 50 - 500 dm-3 range of the samplesolution. The relative standard deviations (n=5) were 3.8% for 0.10mg Cu(II)/100 cm3, 4.7% for 0.05 mg Cu(II)/100 cm3.The proposed method was applied to the determination of trace amounts ofcopper(II) in water samples. (Keywords: Preconcentration, copper(II), chitosan, tungsten metalfurnace, electrothermal atomic absorption spectrometry)