[Determination of aniline in water by flow injection spectrophotometry]

A new flow injection analysis spectrophotometric method for the determination of aniline in water sample was introduced. It is based on the chromogenic-reaction of diazotization-coupling with 1-naphthol in basic media, and coupled with the flow injection analysis for the determination of aniline. The absorbance intensity was registered in this reaction solution at 495 nm. The volume of the sample loop, the length of the reacting coil and chromogenic coil, the flow rate of reagent, the reagent concentrations of H2 SO4, NaNO2, NaOH and 1-naphthol, and the effect of coexistence ions were studied. The calibration graph is linear in the range of 0.005-2.0 mg x L(-1). The detection limit is 0.001 mg x L(-1), and the RSD was 0.7% (c = 0.25 mg x L(-1), n = 11). The proposed method is simple, accurate, sensitive and rapid, and was successfully applied to the determination of aniline in tannery wastewater with the recoveries in the range of 98.0%-103.0%.