Photometric redox determination of bromate ions in drinking water

Abstract

A procedure is developed for the selective photometric redox determination of bromate ions in drinking waters of different types. Methylene Blue (MB), Variamine Blue (VB) and Safranin T (SAF) are studied as irreversibly oxidized redox indicators. The limits of detection for bromate ions are 0.4 and 1 μg/L for MB (VB) and SAF, respectively. Using MB as an indicator at the concentration of bromate ions 1 μg/L, the acceptable mass ratios of concomitant ions are as follows: IO 3 − , NO 2 − (1: 60); ClO−, ClO 2 − (1: 100); ClO 3 − , ClO 4 − IO 4 − , Br− I− (1: 200). In the concentration range of bromate ions 1–10 μg/L, the total determination error is 5–7%.