Simultaneous Determination of Copper(II) and Cobalt(II) Ions, Copper(II) and Manganese(II) Ions in Drinking Water Using Indicator Test Tubes Based on Carboxylic Cation-Exchangers

Resumo

We investigated a possibility of determining two metal ions (Cu²⁺ and Co²⁺, Cu²⁺ and Mn²⁺) in a single water sample using an indicator test tube filled with a carboxylic cation exchanger of a macrocellular (KB-2E-10, KB-2E-16) or a macroporous (Tokem-250) structure. Under dynamic conditions, the separation of the chromatographic zones of colored Cu²⁺ and Co²⁺ ions was achieved in the presence of water macro components, that is, Ca²⁺ and Mg²⁺ ions. An analytical reagent, formaldoxime, was used to determine colorless Mn²⁺ ions. The performance characteristics of the developed procedures are determined. The lowest limit of detection for ions was obtained using a KB-2E-16 cation exchanger; it is 0.016 mg/L for Cu²⁺, 0.045 mg/L for Co²⁺, and 0.003 mg/L for Mn²⁺. The proposed procedures were used to analyze real samples for the concentration of Co²⁺ and Cu²⁺ or Mn²⁺ and Cu²⁺ on their simultaneous presence. The accuracy of the results was evaluated by the standard addition method.