Determination of adsorption and kinetic parameters for methyl tert-butyl ether synthesis from tert-butyl alcohol and methanol

Methyl tert-butyl ether (MTBE), a high-octane blending agent for motor gaso line, is produced by reacting directly tert-butyl alcohol (TBA) with methan ol using Amberlyst 15 ion-exchange resin, which acts as both catalyst and a dsorbent. Experiments were carried out in a fixed-bed reactor in the temper ature range 318-328 K using rectangular pulse input and measuring the eluti on profiles of TEA, MTBE, and H2O. A mathematical model based on a quasihom ogeneous kinetics was developed, which assumes the reaction in the polymer phase to be homogeneous. The kinetic parameters, as well as tile adsorption equilibrium constants of water, TEA, and MTBE in methanol together with th eir dependence on temperature, were determined by tuning the simulation res ults to fit the experimental data using a state-of-the-art optimization tec hnique,the genetic algorithm. The model was further validated using the tun ed adsorption and rate parameters to predict other experimental results. Th e kinetics reported in the present study were obtained under conditions fre e of both external and internal mass transfer resistance. The enthalpy and entropy of adsorption obtained from Arrhenius plots were found to be consis tent with thermodynamics. (C) 2001 Academic Press.