An enhanced performance assessment at process level would require an effective mass transfer coefficient K eff that captures both structure-independent, macro-pore diffusivity, as well as structure-dependent, micro-pore diffusivity. Indeed, several investigations have already revealed a dependence of diffusivity on micro-pore, molecular loading. As gas diffusion and adsorption are, ultimately, determined by a MOF's structural properties, we suggest to include micro-pore gas diffusivity, provided for each MOF structure through GCMC simulations, into the process simulation of CO 2 capture performance by means of K eff , as conceptually visualized in Figure .