A convenient method for determination of p-phenylenediamine (PPD) in wastewater has proposed, based on the perturbation of a non-equilibrium stationary state near a bifurcation for the Belousov-Zhabotinskii (B-Z) reaction, due to this point being very sensitive to the surrounding change. Results indicate that the change of the potential (ΔE) is linearly proportional to the negative logarithm concentration of PPD (-logC) in the range of 4.68 × 10-7 - 1.95 × 10-5 mol L-1 (r = 0.9981) with a limit of detection (LOD) of 9.50 × 10-8 mol L-1. A good recovery was obtained at ca. 95.1 to 102.3%.
non-equilibrium stationary state; Belousov-Zhabotinskii reaction; p-phenylenediamine determination