The aldol condensation of acetone to diacetone alcohol (DAA) has been accomplished with catalytic distillation (CD). A steady-state, rate-based model for the reaction zone of the CD column is developed and fitted to the experimental data which were presented in Part I of this paper. This model is unique in that it considers external mass transfer between the liquid phase and the catalyst surface. The main purpose of this model is to predict production rates and product selectivities. The formation of DAA proved to be an excellent system for the study of external mass transfer effects in catalytic distillation. The model fits the experimental data quite well, but could not be applied a priori due to the random nature of flow patterns in packed columns. However, it may be possible to predict the performance of larger diameter columns since liquid distributors improve the reproducibility of the now pattern.