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 tested kinetic models it is showed that the multitubular design is characterized by an optimal temperature profile throughout the bed length which results in reduced catalyst aging, less catalyst installed and minimized by-products formation. The advantages of multitubular over adiabatic reactors are also discussed in terms of flexibility with respect to changes in feedstock composition and flowrate. These advantages an enhanced by shifting from Amberlyst 15, the ion-exchange resin which is the most used etherification catalyst, to the more acidic and active Amberlyst 35.