Alkane/alkene mixture diffusion in silicalite-1 studied by MAS PFG NMR

The diffusivity of n-alkanes and n-alkenes (C2 to C6) and their mixtures in silicalite-1 was studied by magic-angle spinning pulsed field-gradient nuclear magnetic resonance (MAS PFG NMR) at the temperatures of 273 K, 313 K and 373 K. It could be proved that there is no significant difference between the diffusivities of alkanes, alkenes and their mixtures for equal carbon numbers and equal total loading. The diffusivities of the alkanes, alkenes and their mixtures are found to monotonically decrease with increasing carbon number, in agreement with the results obtained in MD simulations with n-alkanes in silicalite-1.