Simultaneous kinetic determination of cobalt, nickel and iron by coupling stopped-flow techniques and charge coupled device detection Original Research Article

Two kinetic approaches were applied for the simultaneous determination of cobalt, nickel, and iron with multiple linear regression (MLR) method, using the entire kinetic curves or the initial rates of the reaction. The predictive ability of MLR method is based on the slight kinetic differences of these metals which occur at a great number of wavelengths when they react with xylenol orange as a common ligand. The reactions were monitored using a charge coupled device (CCD) UV–VIS spectrophotometer attached to a stopped-flow system. This instrumentation allowed to obtain kinetic data at a maximum of 2048 wavelengths simultaneously. The method was successfully applied to the simultaneous determination of these metals in alloys and the results obtained from the two kinetic approaches were compared.