Analytical Sciences

Abstract − Analytical Sciences, 21(5), 549 (2005).

Simultaneous Spectrophotometric Determination of Hg2+, Pb2+, and Cu2+ by Zn(dmit) Using the Multivariate Calibration Method
Wagner J. BARRETO,* Sônia R. G. BARRETO,* Leila D. RUIZ,* Dilson N. ISHIKAWA,** and Ieda S. SCARMÍNIO***
*Laboratório de Físico-química Ambiental, Departamento de Química, Universidade Estadual de Londrina, Caixa Postal 6001, CEP 86051-990, Londrina, PR, Brazil
**Departamento de Química, Universidade Estadual de Londrina, Caixa Postal 6001, CEP 86051-990, Londrina, PR, Brazil
***Laboratório de Quimiometria em Ciências Naturais, Departamento de Química, Universidade Estadual de Londrina, Caixa Postal 6001, CEP 86051-990, Londrina, PR, Brazil
This work investigates the applicability of the anionic complex [NBu4]2[Zn(1,3-dithiol-2-tione-4,5-dithiolate)2] on the simultaneous spectrophotometric determination of transition metals. Principal Component Regression was used in the data analysis. This method was used to determine Hg2+, Cu2+ and Pb2+ in water solution, at t = 0, 20 and 60 min of reaction. The root mean square errors (rms) for Hg2+, Cu2+, Pb2+ were 1.92 × 10-7, 1.89 × 10-7 and 9.35 × 10-8 for t = 0 min, 1.79 × 10-7, 2.1 × 10-7 and 2.22 × 10-7 for t = 20 min and 1.22 × 10-7, 1.31 × 10-7 and 1.10 × 10-7 for t = 60 min, respectively. Results showed the viability of the method in determining concentrations of metallic ions in aqueous medium with high spectral overlap. It is an efficient alternative method for exploring the kinetic behavior of multi-components systems of interest in physicochemical research.