Effect of some Interfering Ions on the Polarographic and Spectrophotometric Determination of Cyanide and Sulfide Ions in Water

Abstract

Spectrophotometric and polarographic techniques were used for cyanide and sulfide ions determination. Chloramine-T and barbituric acid were used as reagents for complex formation and 0.5M H3BO3+ 0.1M KOH and 0.02 M ascorbic acid + 0.018 M disodium EDTA + 100 mL of 1M NaOH supporting electrolytes for polarography. The Interference effect of the interfering ions Cl - , Ca2+, Mg2+, Fe3+, and Cu2+ was studied. For eliminating the effect of interference , distillation method was used for distillation of cyanide solutions. The concentration of cyanide ion in several samples of drinking water, natural water and waste water were determined by both techniques. The linearity of cyanide determination by spectrophotometric was ranged from (0.05 - 0.5 ppm) at a wavelength (578 nm). The linearity for cyanide ion determination by polarography was ranged from (0.02 - 0.2 ppm).