Multianion analysis, application of high performance and related chromatographic techniques - Determination of Anions in Natural and Treated Waters - page 707

13.1.3 Aqueous precipitation
13.1.3.1 Chloride, bromide, iodide, nitrate, nitrite and thiocyanate
The procedure described by Stetzenback and Thompson [2] discussed in section 13.1.1.2
has been applied to the determination of these anions in rainwater.
13.1.3.2 Nitrate and nitrite
Imanari et al. [8] describe a method for determining nitrate and nitrite in rainwater by
separation with high performance liquid chromatography followed by electrochemical
detection. The eluate from the column was passed through a reductor column which
converted the nitrate to nitrite and the two peaks were then measured electrochemically.
The recoveries were 99.7 ± 2.6% for nitrate and 100.5 ± 3.0% for nitrite. A similar
technique for determining nitrate and nitrite in water was reported by Ishigami et al. [9].
13.1.3.3 Chloride, bromide and iodide
Moss and Stephen [10] determined chloride, bromide and iodide in rainwater by
converting them to aklylmercury(II) halides and measurement by high performance liquid
chromatography.
13.1.4 Trade effluents
13.1.4.1 Thiosulphate and polythionates
Takana et al. [11] used high performance liquid chromatography on an anion-exchange
column with differential pulse polarographic detection to the determination of
thiosulphate and tri, tetra-, penta- and hexa-thionates in trade effluents. The method is
accurate to within 10% at the 0.001−1m M concentration range.
13.2 Ion exclusion chromatography
13.2.1 Non saline waters
13.2.1.1 Sulphide and sulphite
The ion chromatographic determination of weak acid anions is complicated by ion
exclusion in the suppressor column, resulting in faster elution and sharper peaks, directly
proportional to the degree of exhaustion of the suppressor column [12]. A 10mg
L−1nitrite standard showed a 37% increase in peak height over an 8h period when
monitored