Conceptual design of reactive distillation for selectivity improvement in multiple reactant systems

Reactive distillation (RD) can be effectively used to improve selectivity by manipulating the composition profiles of reactants and products inside the reactive zone of a RD column. One can obtain close to quantitative yields if the azeotropes, if any, do not limit the separation. As against the single reactant systems (i.e. condensation, dimerization), more design options are available in the case of multiple reactants (e.g. esterification, cross aldol condensation) and we propose design guidelines for such systems in this work. The parametric studies for the representative hypothetical reaction systems, involving both reversible and irreversible reactions, form the basis of these guidelines. The cases associated with non-ideality through formation of azeotropes are also discussed. The analysis is further extended to real processes involving reactions such as cross aldol condensation, esterification and transesterification.