A method for the modeling of a seepage catalytic packing internal (SCPI) in a catalytic distillation column was developed and applied to the simulation of a catalytic distillation (CD) process. Based on the structure of the internal, rigorous mathematical models consisting of differential algebraic equations were developed to predict the temperature and composition profiles in the CD column. Based on the gPROMS platform, the gPROMS language was used to compile three modules, one for the reaction and the other two modules for hydrodynamic calculations and heat and mass transport calculations. In addition, a graphical user interface (GUI) design and the corresponding port design were implemented for each unit module to clearly represent the flow-sheet of the catalytic distillation process. According to the characteristics of the model, a new approach was proposed to avoid convergence difficulties and to improve the stability of the calculations. This approach was demonstrated to be an efficient method, which can reduce the simulation time and still accurately predict the results. Mathematical models and corresponding programs of reaction, separation, and the flow-sheet of CD process were validated. The simulated results were in good agreement with the experimental results, indicating that the simulation methods established in this paper are feasible. Furthermore, the gPROMS is a reliable and suitable technique for studying the catalytic distillation process of SCPI. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.