Ion chromatographic determination of bromate in drinking water by post-column reaction with fuchsin

Bromate deriving from ozonation treatment of bromide containing waters are analyzed by ion-exchange chromatography with spectrophotometric detection after post-column reaction with fuchsin in low pH medium. An anion-exchange column was used with 2.7 mM carbonate-0.3 mM hydrogencarbonate eluent. The eluent from the column was then allowed to react with a SO2-reduced fuchsin solution and then with a diluted HCl solution at 65 degrees C. The developed colour of the final product was measured spectrophotometrically at 530 nm. Linearity was checked up to 50 IJ mu g/l with a 200-mu l injection loop (r(2)=0.9997) and up to 100 mu g/l of bromate with 100 mu l loop (r(2)=0.9939). Nitrate, sulfate, bromide, phosphate, fluoride did not interfere at 100 mg/l concentration level; only nitrite at concentration levels greater than 3 mg/l caused partial overlapping with bromate peak, but this value is not likely to occur in common drinking water. The detection limit (3 sigma) is 0.1 mu g/l (1 mu g/l propagation error approach). (C) 1999 Elsevier Science B.V. All rights reserved.