Abstract The extraction mechanism of capsaicin adsorption by anion exchange resin was studied and the corresponding kinetic equation was obtained. The control step of the ion exchange process was established according to the dynamic boundary model, and the influence of the process conditions on the exchange rate was examined. The results showed that the diffusion control of the liquid film was converted into the diffusion control of the resin particles at 10 min. It was calculated that the apparent activation energy of the exchange process was 12.6 kJ/mol, the reaction order was 0.268, and the rate constant was 2.12×10-3. In addition, the adsorption isotherms of capsaicin were well fitted with the Freundlich equation when the pH was between 5.0 and 6, and the kinetics equation for the adsorption of capsaicin by the anion-exchange resin based on the Freundlich model was deduced.
