A diffusivity model for gas diffusion through fractal porous media

► We have built a fractal model for gas diffusivity in porous media. ► The proposed gas diffusivity model is expressed as a function of micro-structural parameters of porous media. ► Effects of parameters such as porosity, microstructures of porous media and fractal dimensions on gas diffusivity are analyzed. ► Diffusivities predicted by present fractal model are compared with experimental data and a fair agreement among them is found.