[Simultaneous determination of copper and iron by catalytic kinetic spectrophotometry]
Chi-yang He1, Gen-hua Wu, Qiong Cheng
1Department of Chemistry-Anqing Normal College, Anqing 246011, China.
Abstract:
A simultaneous catalytic effect copper (II) and iron (III) on the oxidation of acid chrome blue K by potassium bromate in dilute sulfuric acid medium was observed. But there was an obvious difference in their reaction rates, and the ratio of the reaction constant changed with time. And their spectral addiitive properties were not satisfactory. The simultaneous determination of copper and iron by catalytic kinetic spectrophotometric method was realized by using a three-layer Levenberg-Marquardt BP neural network to cope with the experimental data. The optimum conditions of reaction and determination were studied. The calculation results of the determination in synthetic samples and human hair were satisfactory.
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