Reactive distillation is a unit operation that combines reaction, using either liquid or solid catalyst, and separation in a single piece of equipment. This process is particularly useful for enhancing conversion of equilibrium-limited reactions. A comprehensive modeling study of mass transfer phenomena in solid-catalyzed reactive distillation processes is documented here. Transport resistance at the vapor-liquid, liquid-solid and within the catalyst pellet, were examined in detail using multicomponent reaction-diffusion and packing hydraulic models within a rate-based modeling framework.; The multicomponent reaction-diffusion model examines intrapellet catalyst resistance and calculates an effectiveness factor that is used to modify intrinsic reaction rates calculated from bulk liquid compositions and temperatures. It uses the Generalized Maxwell-Stefan equations to determine molar flux. Model results were validated with experimental data from two systems, methyl tert-butyl ether (MTBE) and tert-amyl alcohol (TAA). Results from a parametric study were used to develop design heuristics for reactive zone location and operation.; The packing hydraulic model, which accounts for liquid flow in the form of rivulets, films and drops, determines liquid holdup, pressure drop, mass transfer coefficients and interfacial area for different packing. Two commercial geometries, that of bale packing and catalytic structured packing, were studied. Bale and structured packing results were validated with pilot-scale and commercial data from two binary non-reactive systems (cyclohexane/n-heptane and acetone/MEK). A scale-up procedure based on wall effects was developed to calculate capacity and efficiency in large columns.; A rate-based model was used to simulate a pilot-scale reactive column, and results validated with experimental data for the TAA system. Results from two case studies were used to develop heuristics for design and operation of reactive columns. Reactive distillation processes with and without a pre-reactor were compared. The results from a comparison between reactive distillation and conventional reactor-column processes highlight advantages and disadvantages of each process.; This dissertation demonstrates the use of a rate-based model for reactive column design and includes three unique features: a detailed discussion of reactive column devices and hydraulics, an examination of intrapellet and interpellet diffusion resistance for distillation conditions, and development of heuristics for design and operation of solid-catalyzed reactive distillation columns.
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