Catalytic Kinetic Spctrospectrophotometric Determination of Trace Copper(II) with 7-(5-carboxy-1,3,4-triazole)chlorophosphonazo and Hydrogen Peroxide

A new catalytic kinetic spectrophotometry for the determination of trace copper was established based on the catalytic action of Cu2+ on the oxidative fading reaction between 7-(5-carboxy-1,3,4-triazole)-chlorophosphonazo(CTACPA) and H2O2 in the medium of HAc-NaAc at pH 4.0 and heating conditions.The maximum absorbance shows at 535 nm.The calibration curve was linear in the range of(0.004~0.2) mg/L for Cu2+,and the linear regression equation was ΔA=3.026 0ρ-7.24×10-3(ρ: μg/mL) with the correlation coefficient of 0.999 4.The detection limit is 2.90×10-10 g/mL for copper.The method is applied to determine trace copper in hair and lake water samples.The results are in good agreement with the values obtained by atomic absorption spectrometry.