| Dilute acetic acid is produced in many chemical and petrochemical industrial applications. One of the current technologies for removing the acetic acid from water is by azeotropic distillation. It is very energy-consuming and the costs involved in the manufacture and maintenance of the equipment is very high because of the very corrosive nature of concentrated acetic acid.;Preliminary computer simulation showed that catalytic distillation could be an alternative and more competitive process. In the catalytic distillation column, methanol is introduced to react with acetic acid. The reaction product, methyl acetate, is removed from the column top and water is discharged from the bottom. In this way, a relatively small amount of product is withdrawn from the column top and the acetic acid concentration in the column is kept lower than that in the feed. Therefore, both energy consumption and investment costs can be reduced.;In this thesis research, catalytic distillation experiments for the removal of acetic acid from water were conducted in a 100 mm diameter column installed with proprietary column internals composed of catalyst units and separation trays. An ion exchange catalyst (Amberlyst 15) was used to accelerate the reaction. The effects of feed rate, reflux ratio, product rate and feed location on the operation performance were investigated. For the feed containing 2.5 to 9.9 wt% of acetic acid in water, more than 50 wt% of the acid was removed in the 1.5 m high test column.;Detailed studies were conducted on the reaction kinetics, vapor-liquid equilibrium and separation efficiencies for the modeling and simulation of the catalytic distillation process. A simulation program was established by incorporating the basic models into a commercial simulation package. The models and the simulation program were verified by a variety of experimental data.;From the simulation results, it is estimated that catalytic distillation consumes only 14.8% of the energy that simple distillation does for the separation of dilute acetic acid from water. The investment is reduced because of the smaller column size and the avoidance of the corrosion problem. |
