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

Abstract

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 1.08 by pseudo rate method, respectively, with a rate constant, k , of 0.054 [(M −1.08 ) s −1 ]. In addition to pseudo rate method, the half-life approach was used to calculate the overall reaction order to verify the accuracy of pseudo rate method. The overall reaction order was determined to be 1.9 by the half-life method. The overall reaction order based on the two methods studied was approximately 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 solvent violet 9 (SV9). Based on the FTIR spectra, it was confirmed that the molecular structure of the precipitate matched that of solvent violet 9.

Optical absorption and photoluminescence properties of Cucurbita maxima dye adsorption on TiO2 nanoparticles

“…Where A absorbance, ε is the molar absorption coefficient, C is the molar concentration, and l is the optical path length [21]. Broadening of the bands in the range 635-674 nm was observed for higher concentrations, indicating chlorophyll-chlorophyll interactions, as has been observed in similar studies [19].…”