A PSEUDO-STEADY-STATE APPROACH FOR TRIPHASE CATALYSIS IN A BATCH REACTOR

The reaction of 2,4,6-tribromophenol with allyl bromide catalyzed by triphase catalyst in an organic/alkaline solution was studied. The effects of the operating conditions on the conversion were investigated in detail. The apparent reaction rates were observed to obey the pseudo-first-order kinetics with respect to the organic reactant when excess 2,4,6-tribromophenol was used. An optimal amount of potassium hydroxide was obtained to enhance the overall reaction. The linear relation of the amount of catalyst to the apparent rate constant was presented. Also, a kinetic model in terms of the intrinsic reactivity and intraparticle diffusion limitations for a spherical catalyst is proposed to describe the triphase catalytic reaction system. The pseudo-steady-state approach to the mass balance equation was employed to get the solution. The effective diffusivity of the reactants within the catalyst can be obtained from this model and used to predict the observed reaction rate. The predicted values were consistent with the experimental data.