Simultaneous Analysis of Co2+, Cu2+ Mn2+, Ni2+ and Zn2+ in The Ultraviolet Region Using 4-(Pyridil-2-AZO) Resorcinol and Multivariate Calibration

ABSTRACT

A multicomponent spectrophotometric methodology for the simultaneous determination of Co²⁺, Cu²⁺, Mn²⁺, Ni²⁺ and Zn²⁺ in aqueous solution is reported, using (4-(pyridil-2-azo) resorcinol), a diode array spectrophotometer and multivariate calibration by partial least-squares and principal component regerssions. Spectra are recorded in the UV region. The 225 – 320 nm range is selected as optimal, through a criterion based on tederivatives of the differences between individual spectra, which compares favorably with a genetic algorithm. The methodology is applied to the simultaneous determination of the five than 1.5 mgL^?1. The best result are obtanied at pH 9.0, with average absolute errors of prediction lower than 0.09 mgL^?1