Simultaneous determination of Co~(2+) and Ni~(2+) content in alloy electrolyte by double-wavelength spectrophotometric method

A double-wavelength spectrophotometry was used to determine the Co~(2+) and Ni~(2+) content in nickel-cobalt alloy electrolyte simultaneously,using PAR-ethanol solution as developer.The maximal absorption wavelengths of Co~(2+) and Ni~(2+) are 510 nm and 490 nm respectively,and thereby mensuration wavelengths were obtained.The determination ranges of the contents of Co~(2+) and Ni~(2+) by the method are 30~1 200 μg /L and 25~1 000 μg /L respectively.The developing conditions were obtained through the discussion on the influences of the developer content,acidity and developing time on absorbency.Recovery experiments on four kinds of nickel-cobalt alloy baths reveal high precision,high recovery rate of 99.7%,easy operation and good practicability of the method.