A method for determination of hydrazine based on the Belousov–Zhabotinskii reaction is proposed. The addition of the hydrazine to the oscillating system increases the oscillating amplitude. This increase in oscillating amplitude was used as the analytical signal. To obtain a maximum value of analytical signal in determination of the hydrazine, the effects of different concentrations of malonic acid, potassium bromide, potassium bromate, cerium(IV) and sulfuric acid were investigated and the optimum concentration of each component was used for further experiments. The analytical signal is linearly proportional to the logarithm of the hydrazine concentration over the range of 1×10-6 M to 1×10-3 M (1 M=1 mol dm-3) under optimum conditions. The obtained LOD (2σ) was 1×10-6 M and the relative standard deviation (RSD) for five measurements of1:1×10-4 M hydrazine was 5%. The influences of some potential sources of interference were also investigated.
