Abstract A model for trioxane synthesis in a coupled reactor/column system is developed. The performance of the coupled system, in terms of conversion, time/space yield and energy utilizing efficiency is investigated by simulation. Results show that if the heat input is given, there exists an optimal reflux ratio at which the time/space yield and the energy utilizing efficiency reach their maxima. As for design case, when the heat input and the reflux ratio are fixed, there exists an optimal number of trays: more trays give no improvement on the time/space yield and the energy efficiency, while less trays decrease the time/space yield and the energy efficiency significantly. Experiments are carried out to show the validity of the simplified model.