Bridging the gap between macroscopic and NMR diffusivities

A new and fast pulse technique for the simultaneous determination of both the pore diffusion coefficients in, and the rate constants for adsorption and desorption at zeolitic materials are presented. The diffusivities determined are the actual diffusivities, not influenced by any external process, which is also the case for diffusivities obtained using nuclear magnetic resonance. The absolute values for the rates of adsorption and desorption are in the same order of magnitude calculated by the kinetic gas theory. The calculated equilibrium constants for and heat of adsorption are in good agreement with values reported in literature.