Simulation Studies of Catalytic Distillation for Removal of Water from Ethanol Using a Rate-Based Kinetic Model

Abstract

A new approach based on catalytic distillation (CD) technology was proposed to remove water from ethanol, by reaction with isobutylene to form tert-butyl alcohol (TBA) and ethyl tert-butyl ether. Reaction within the CD column was calculated using a rate-based kinetic model with the simulation package Aspen Plus. A sensitivity analysis of the effect of the key design and operating factors on the column performance was performed. The most important factors affecting water conversion, TBA selectivity, and reboiler duty are the operating pressure and reaction temperature, distillate-to-feed ratio, amount of catalyst, and feed and reaction stage location. Optimization of operating variables found that the CD process offers potential advantages of reduced energy consumption and reduced capital cost over the traditional approaches for the removal of water from ethanol.