This contribution proposes a multilevel modelling approach as a tool for the decision-making task in the early design stages of reactive distillation processes. The proposed model involves formulating the simulation problem at different levels of increasing degree of complexity, in which mass, energy and momentum balances are conveniently applied to represent the behavior of the process. A successful realization at the outer level (column-level) would suggest relaxing constraining assumptions and stepping up to the more rigorous modelling framework (task-level). Both levels have been linked by the extent of reaction vector, which allows establishing whether or not the corresponding models are well specified and mutually consistent. Furthermore, this approach allows determining whether or not the business-related decision variables cope with the operational constraints imposed by the problem formulation. The proposed approach has been applied to the synthesis of methyl tert-butyl ether in an staged column.