Spectrophotometric determination of nitrate and nitrite in natural water samples based on an oxime formation reaction of phenol

Abstract

The spectrophotometric method for the determination of nitrate reported by Velghe and Clays was modified.The modified method was applied to the determination of nitrate and nitrite in natural water samples(well, river, and seawater).In the modified method, a sodium chloride solution was used instead of hydrohloric acid as the source of chloride for reducing nitrate.The sensitivity of this method was comparable to that of ion chromatography and that of HPLC with UV detection.The results obtained by the proposed method were in good agreement with those obtained by the chromatographic methods.The proposed method could be applied to the determination of nitrate of low concentration levels in seawater sample.