MULTITUBULAR REACTORS FOR ETHERIFICATIONS

Both fixed-bed adiabatic reactors and multitubular reactors with heat removal by tempered water are employed in the industrial synthesis of methyl tert-butyl ether (MTBE) from methanol and isobutylene. Through selected examples based on simulations performed with thoroughly teste d kinetic models it is showed that the multitubular design is characte rized by an optimal temperature profile throughout the bed length whic h results in reduced catalyst aging, less catalyst installed and minim ized by-products formation. The advantages of multitubular over adiaba tic reactors are also discussed in terms of flexibility with respect t o changes in feedstock composition and flowrate. These advantages an e nhanced by shifting from Amberlyst 15, the ion-exchange resin which is the most used etherification catalyst, to the more acidic and active Amberlyst 35.