Diffusion in ZSM-5 supported membranes was studied from ambient to 723K. The Maxwell–Stefan equations were used for the interpretation of the results. From these, micropore diffusion coefficients and apparent diffusion activation energies were obtained. The results were described by:

n-butane:     D(m2/s) = 8.7 x 10-9exp[-11.7(kJ/mol)/RT]

isobutane:     D(m2/s) = 3.6 x 10-8exp[-31.2(kJ/mol)/RT]

B.Millot, A.Méthivier, H.Jobic, H.Moueddeb, J.A.Dalmon: Microporous and Mesoporous Materials, 2000, 38[1], 85–95