Microdetermination of bromide in water by gas chromatography

For the determination of micro order bromide in waters, a rapid, selective and sensitive method was studied. Bromide reacted with citric acid and potassium permanganate to form pentabromoacetone, which then turned into bromoform. The bromoform was measured by a head space gas chromatograph. The ion-exchange chromatograph (Amberlite CG-400, 10 mm i.d. × 70 mm; elutant, 0.1 M sodium nitrate, 70 ml and 0.5 M sodium nitrate, 25 ml) was applied to bromide without interfering substances such as chloride and phenols. Bromide of ppb levels in water can be accurately determined by ion-exchange chromatograph, potassium permanganate oxidation and head space gas chromatograph (ECD).