Integration of MFI Zeolite Membranes in the Light Gasoline Isomerisation Process

Abstract : Tests aiming at separating normal pentane from a light gasoline isomerate through a MFI zeolite composite membrane were carried out. The performances of this membrane sample were studied as a function of total hydrocarbon pressure upstream of the membrane as well as the temperature. Maximal permeate flux, close to 2 kg/m2.h, was observed at 250°C - 2 bar total hydrocarbon pressure. The normal pentane weight fraction was more than threefold higher in the permeate than in the feed. In a second step, a fully heat-integrated light gasoline isomerisation process loop integrating a MFI zeolite membrane-based separation was simulated and optimised. Integration of MFI zeolite membranes in this process proved to be valuable only if their cost is lower than 1000 EURO/m2.