Direct experimental observation of segregation and siting in zeolites is, however, difficult. Molecular simulation can provide predictions of both molecular-level siting and macroscopically observed adsorption isotherms.
Simulation is thus atool for elucidating the effects of segregation on adsorption thermodynamics.
We are using molecular simulations to find out when and why segregation occurs in zeolites, as well as how it affects the adsorption thermodynamics. More complicated systems, such as cyclohexane, methanol, and aromatics in silicalite have also been studied. We can use the results from these simulations as data to test IAS theory and to link deviations from IAS behavior with any observed molecular segregation in the simulations. The molecular-level information from the simulations allows us to offer anexplanation for this surprising result. Siting predictions from simulation have been tested and verified by 129Xe and 19F NMR in our laboratory.