Figure 6: Mass transport of alkanes in nanoporous matrix.

Rescaled permeance K × (n+n₀) for different n-alkanes as a function of the free volume fraction (with n₀=2). The colour code is the same as Fig. 1: methane (black), propane (blue), hexane (green), nonane (yellow) and dodecane (red). The dashed line is the prediction in equation (11), written here as , with K₀=2.38 × 10⁻¹⁵ m² Pa⁻¹ s⁻¹, α=0.23, obtained from a best fit. Inset: Permeance K versus the loading for various alkanes. The dashed lines correspond to the previous prediction in terms of the loading, using the relationship , with β=0.6, see Supplementary Fig. 7.