Electrocatalytic oxidation and voltammetric determination of hydrazine on the tetrabromo-p-benzoquinone modified carbon paste electrode

The electrochemical properties of hydrazine studied at the surface of a carbon paste electrode spiked with p-bromanil (tetrabromo-p-benzoquinone) using cyclic voltammetry (CV), double potential-step chronoamperometry and differential pulse voltarnmetry (DPV) in aqueous media. The results show this quinone derivative modified carbon paste electrode, can catalyze the hydrazine oxidation in an aqueous buffered solution. It has been found that under the optimum conditions (pH 10.00), the oxidation of hydrazine at the surface of this carbon paste modified electrode occurs at a potential of about 550 mV less positive than that of a bar carbon paste electrode. The electrocatalytic oxidation peak current of hydrazine showed a linear dependent on the hydrazine concentrations and linear analytical curves were obtained in the ranges of 6.00 x 10(-5) M - 8.00 x 10(-3) M and 7.00 x 10(-6) M -8.00 x 10(-4) M of hydrazine concentration with CV and differential pulse voltarnmetry (DPV) methods, respectively. The detection limits (3 sigma) were determined as 3.6 x 10(-5) M and 5.2 x 10(-6) M by CV and DPV methods. This method was also used for the determination of hydrazine in the real sample (waste water of the Mazandaran wood and paper factory) by standard addition method.