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SCALE-UP OF REACTIVE DISTILLATION COLUMNS WITH CATALYTIC PACKINGS Achim Hoffmann, Christoph Noeres, Andrzej Górak Department of Chemical Engineering, Dortmund University, 44221 Dortmund, Germany ABSTRACT The scale-up of reactive distillation columns with catalytic packings requires the knowledge of reaction kinetics, phase equilibrium and packing characteristics. Therefore, pressure drop, liquid holdup and separation efficiency have been determined for the catalytic packing MULTIPAK ® . A new hydrodynamic model that describes the counter-current gas-liquid flow for the whole loading range and considers the influence of the column diameter has been implemented into a rate- based column model. Simulation results for the methyl acetate synthesis are compared with pilot plant experiments that cover a wide range of different process conditions. The experiments are in good agreement with the simulation results and confirm the applicability of the modelling approach for reactive distillation processes with catalytic packings. INTRODUCTION The combination of heterogeneously catalysed reaction and separation in one single process unit, known as catalytic distillation, is one of the most common applications of the multifunctional reactor concept [1]. In comparison to the conventional approach, where reaction and separation are carried out sequentially, catalytic distillation can considerably improve the process performance [2,3]. One of the advantages is the elimination of equipment for product recovery and recycling of unconverted reactants, which leads to savings in investment and operating costs. Catalytic distillation may also improve selectivity and mass transfer and avoid catalyst fouling [4]. Even if the invention of catalytic distillation dates back to 1966 [5], the number of processes in which catalytic distillation has been implemented on a commercial scale is still quite limited but the potential of this technique goes far beyond today’s applications [6]. Different process configurations can be chosen to carry out catalytic distillation [7]. The installation of a solid catalyst inside a distillation column attains the largest