The development of a new inhibition kinetic spectrophotometric method for the determination of phenylhydrazine

Anew sensitive kinetic method has been developed for the determination of trace amounts of phenylhydrazine in the range of 1.08x10-7 to 1.08x10-6 g/cm3. The detection limit of this method is 0.008 ?g/cm3, based on the 3Sb criterion. Themethod is based on the inhibitory effect of phenylhydrazine on the oxidation of Victoria Blue 4-R by KBrO3. The reaction was monitored spectrophotometrically at 596.3 nm. The method development includes the optimization of the reagent concentration and temperature. The kinetic parameters of the reaction are reported and a rate equation is suggested. The effects of certain foreign ions upon the reaction rate were determined for the assessment of the selectivity of the method. The new developed method was found to have fairly good selectivity, sensitivity, simplicity and rapidity. Predlozena je nova osetljiva kineticka metoda za odredjivanje tragova fenilhidrazina u intervalu koncentracija od 1,08x10-7 do 1,08x10-6 g/cm3. Detekcioni limit ove metode je 0,008 g/cm3 baziran na 3Sb kriterijumu. U osnovi metode je inhibitorni efekat fenilhidrazina na reakciju oksidacije indikatorske supstance Viktorija plavo 4-R. Reakcija je pracena spektrofotometrijski na talasnoj duzini od 596,3 nm. Izvrsena je optimizacija koncentracije reagenasa i temperature. Odredjeni su kineticki parametri i predlozene kineticke jednacine. Ispitan je uticaj veceg broja stranih jona na brzinu reakcije. Nova predlozena metoda ima dobru selektivnost, osetljivost, a uz to je veoma jednostavna i brza.