Modelling of a Reactive Distillation in the production process of high purity Cyclohexanone to produce caprolactam

Abstract

Cyclohexanone (ONE) is an important raw material to promote caprolactam (CPL). It is used as a monomer in nylon industries. In the ONE production process, this component needs to be purified from a mixture of cyclohexanol (OL) and some impurities such as 2-cyclohexen-1-one (CXENONE). The concentration of these impurities must be reduced o in order to improve the quality of nylon fibres produced from CPL. The main scope of this work is to model a reactive distillation column where the cyclohexanone (ONE) is separated from a mixture of cyclohexanol (OL) and 2-cyclohexen-1-one (CXENONE). The model is developed in gPROMS, where the kinetic model is implemented alongside with the NRTL equation whose binary interaction parameters are also obtained experimentally. The aforementioned model is validated in a packed distillation column operating at continuous conditions. This experimental setup is used to prove the capacity of the model to explain the real operation conditions. The mathematical model has shown favourable predictions on temperature profiles, concentration profile and conversion of all the compounds in each stage of the column. Finally, the MINLP problem formulation for optimising real operation is suggested along with planned sensitivity studies which will next be tackled.