The Etherification of Methanol and Isobutene in a Catalytic Distillation Column Packed with Zeolite-Beta-Coated Catalytic Packings

Abstract

Zeolite-beta-coated catalytic packings were used to improve the etherification of methanol and isobutene in a catalytic distillation column. The steady-state composition profiles and the characteristics of the reaction in the catalytic distillation column were investigated. The zeolite-beta-coated packing has better characteristics and an activity that is comparable to that of the conventional resin catalyst in both catalysis and the separation of reactants from products. The optimal operating conditions for the catalytic distillation process are a pressure of 0.7 MPa, a methanol/isobutene feed molar ratio of 1, and a reflux ratio of more than 3. The effect of the strong nonlinearity in the vapor−liquid equilibrium of the reactive system on the conversion of isobutene was analyzed on the basis of the experimental results for both catalytic distillation and conventional distillation. There is a valley in the boiling-point temperature surface of the ternary mixture of methanol/isobutene/MTBE. This valley, a...