ALKANESULPHONATES AS ELUENTS FOR THE DETERMINATION OF NITRATE AND NITRITE BY ION CHROMATOGRAPHY WITH DIRECT UV DETECTION

A homologous series of alkanesulphonates were investigated for use as eluents in the ion chromatography of nitrate and nitrite with direct UV detection. The alkyl chain length has a large positive effect on elution strength when a poly(styrene-divinylbenzene)-based ion-exchange column is used. This effect is much less apparent with silica-based columns. Sulphonates from methane- to 1-hexanesulphonate gave excellent separations of nitrate and nitrite, allowing the determination of either without interference in the presence of a 1000-fold molar excess of the other, and making a 1-min assay for nitrate and nitrite possible. The alkanesulphonates can also be used with conductivity detection, allowing the specificity of UV detection to be combined with the versatility of conductivity measurements. © 1990.