Kinetics and mass transfer of organic liquid-phase reactions in the presence of a sparingly soluble solid phase

Several organic liquid-phase reactions are carried out in the presence of a sparingly soluble reactive solid phase which is gradually dissolved during the course of the reaction. The presence of the reactive solid phase complicates the treatment of kinetic data, since the overall reaction rate is influenced by the solubility equilibrium and mass transfer rate of the solid compound. A mathematical model has been derived for an organic reaction system with one reactive solid compound. The modelling concept was applied on a linear multistep reaction system, Claisen condensation, The solubility of the solid compound was measured with batch experiments carried out under nonreactive conditions, and the kinetic parameters for the reaction system were determined from the data obtained by semibatch experiments. Model simulations clarified the behavior of the sparingly soluble reactive compound in the process, indicating that the rate equations describe well the experimental kinetic data.