Ion chromatography trace analysis of anions in seawater is difficult, due to the high chloride concentrations. In contrast to chloride, nitrite, bromide and nitrate absorb UV radiation in the low wavelength range, thus enabling a UV detection of these three anions.
This Application Note describes the separation on a column of the Metrosep Carb 2 - 100/4.0 type with a sodium chloride eluent. This minimizes the influence of the surplus chloride and enables low detection limits.