Determination of p-nitroaniline by the tartrate-acetone-Mn~(2+)-KBrO3-H2SO4 double organic substrate oscillating system using non-equilibrium stationary state

摘要

This paper described the determination of p-nitroaniline in a double organic substrate oscillating system of tartrate-acetone-Mn~(2+)-KBrO3-H2SO4. Under the optimum conditions, temperature was chosen as a control parameter to design the bifurcation point and proposed a convenient method for determination of p-nitroaniline. Results showed that the system consisting of 3.5 mL 0.06 mol L~(-1) tartrate, 4.0 mL 0.7 mol L~(-1) H2SO4, 1.5 mL 1.5×10~(-4) mol L~(-1) MnSO4, 4.0 mL 0.4 mol L~(-1) acetone and 7.0 mL 0.05 mol L~(-1) KBrO3 was very sensitive to the surrounding at 33.5℃. A good linear relationship between the potential difference and the negative logarithm concentration of p-nitroaniline was obtained to be in the range of 2.50×10~(-7) ～3.75×10~(-5) mol L~(-1) with a lower detection limit of 2.50×10~(-8) mol L~(-1).