Primary-Secondary wavelengths Spectrophotometric for improving the Determination of Nitrobenzene Compounds in wastewater

Abstract

In acidic solution the conventional reaction of nitrobenzene with
N-(1-naphthyl)-ethylendiamine-dihydrochloride (NEDA) in the presence
of hydrazine sulfate and nitrite to form a red azo compound has been
applied for the improvement of the determination of nitrobenzene compounds
in water and wastewater by primary-secondary wavelengths spectrophotometry
(PSWS). The updated method can bring out the higher
precision and sensitivity than the ordinary spectrophotometry, but also the
calculation model is stable. The result shows that the relative standard
deviations were less than 2.1 % and the recovery rate of nitrobenzene
between 96 and 104%. The detection limit of nitrobenzene was equal to
0.008 mg/L .