Reactive distillation in a dividing wall column

Reactive dividing wall columns (RDWCs) are highly integrated distillation systems that can simultaneously carry out chemical reactions and multicomponent separations within the same vessel. While reactive distillation columns (RDCs) are well established and dividing wall columns are becoming increasingly popular in chemical processes due to their ability to present significant capital and operating costs savings, RDWCs have not been commercially adopted, in part due to the lack of experimental studies and validated models. Therefore, to increase public literature knowledge in this area, a complex aldol condensation reaction was studied at the laboratory scale.
The first portion on this work focused on experimentally determining the phase equilibria and kinetics of the test system so that the results could be used to construct a simulation. First, vapor-liquid equilibria and liquid-liquid equilibria experiments were used to calculate binary interaction parameters using the non-random two-liquid model. Then, both batch and continuous reaction experiments were carried out and used to develop a power law model for the system’s apparent kinetics. Next, a simplified RDC was designed, built, and tested with the purpose of using the data to validate phase equilibria and kinetics modeling and inform RDWC design. The column successfully operated at steady state, and its data was used to carry out validation on a steady-state, equilibrium-stage model. The RDC experiments and simulation were then used to intensify the process and build a laboratory-scale RDWC. Experimentation was then performed on the RDWC, demonstrating its ability to maintain steady-state and meet process objectives. Finally, the experimental data was used to validate a RDWC model. By using the tools of modeling and experimentation to intensify the aldol condensation test system from kinetics and phase equilibria experiments to a RDC then a RDWC, this work contributed a roadmap for evaluating the commercial potential of a RDWC system. Additionally, this work validated the approach of using scaleable Oldershaw laboratory distillation glassware to investigate a RDWC and for model validation.