Effect of the nonuniform dealumination on the acidity and catalytic activity of faujasite: Part 2. Accessibility of acid sites

The implications of framework aluminum gradients in dealuminated zeolites for catalytic processes in which the reactants cannot penetrate deep inside the crystallite is discussed both theoretically and experimentally. It is shown that the Al distribution curves deduced considering uniform dealumination do not apply for cases where nonuniform dealumination occurs and therefore cannot be directly correlated with the activity shown by nonuniform dealuminated zeolites.