Improvement in the flow injection spectrophotometric determination of zincwith zincon through elevated temperatures

The enhancement of the performance of the zincon method at elevated tempera tures is described. The technique exploits the acquired kinetic energy brou ght about by raising the temperature rapidly and specifically de-masking th e cyanide-metal complexes with cyclohexanone. The rate of determination is increased from 80 to 120 samples per hour due the reduction period of the r ate-determining step. The reduction of the reaction time eliminates interfe rences. The method was evaluated for the determination of zinc from soft dr inks, beer, energy drinks, fertilizer, and steel wool. The % relative stand ard deviation (RSD) was found to be less than 0.5 with a percentage recover y of 97%. The results of the proposed FIA system compare favourably with th ose obtained for a standard ICP procedure.