Kinetic reaction rate method for the determination of hydrazine with spectrophotometric detection

A simple kinetic spectrophotometric method is described for the determinati on of a low-level concentration of hydrazine. The method is based on the in hibitory effect of hydrazine on the reaction of Brilliant Cresyl Blue with nitrite in acidic media. The reaction was monitored spectrophotometrically at 625 nm. The effects of the reagent concentration and the temperature wer e investigated. Hydrazine can be determined in the concentration range 0.05 -5.00 mu g/mL with a limit of detection of 0.040 mu g/mL hydrazine. The eff ects of potentially interfering substances on the determination of hydrazin e were studied. The method was used for the determination of hydrazine in w ater samples.