AbstractA mathematical model of a packed bed distillation column is presented and applied to a binary system in a full scale industrial distillation column with structured packings. The model is reduced by orthogonal collocation to sets of ordinary differential and algebraic equations. A linearized large state space model is then obtained and further reduced by the optimal Hankel norm method in order to obtain a model of manageable size. The model is studied under three different operating conditions in order to cover the feasible operating ranges during the experiments. The experiments carried out with a monoethanolamine‐diethanolamine system show a good agreement with the model implying that a control design based on the model is satisfactory. It is also shown that the control configuration to be used can be easily analyzed by the model, since different input and output structures can be studied. Furthermore, models based on one‐film and two‐film theories are compared in the frequency domain and show that, due to its simplicity, the one‐film theory should be used in control design.