The objective of this paper is test the capabi
lity of the Maxwell-Stefan (M-S) diffusion formulation topredict binary mixture permeation fluxes across a SAPO-34 membrane using only data on pure-componentadsorption isotherms and diffusivities. Experiments were carried out for permeation of CO
2/CH
4, CO
2/N
2,and N
2/CH
4 mixtures across a SAPO-34 membrane with upstream pressures ranging to 7.2 MPa, ensuringthat high occupancies within the zeo
lite layer are reached. Good agreement between the M-S mixture modeland experiments are obtained provided the binary exchange coefficients
12 in the M-S equations are assumedto have high enough values to ensure that intercage hops of the species occur independently of one other.