Liquid-liquid phase reaction between crystal violet and sodium hydroxide: kinetic study and precipitate analysis

To investigate reaction order and kinetic parameters of the reaction between crystal violet (CV) and sodium hydroxide (NaOH), various concentrations of the reactants were applied. The present work also verifies the unknown solid product produced under highly concentrated conditions. The reaction orders of CV and NaOH were determined to be 1 and 1.17 by pseudo-rate method, respectively, with a rate constant, k, of 0.084 [(M-1.17) s-1]. In addition to pseudo-rate method, the half-life approach is use to calculated the overall reaction order to verify the accuracy of pseudo-rate method. The overall reaction order is determined to be 1.9 by half-life method. Compare reaction order gained from both methods, the overall reaction order is determined as ~2. The precipitate formation was observed when high concentrations of CV (0.01~0.1 M) and NaOH (1.0 M) were applied. Fourier transform infrared (FTIR) spectroscopy was used to compare the spectra of the precipitate generated and a commercial so...