Diffusion behavior of the benzene molecule in faujasite-type zeolite studied by double quantum filtered NMR

Structural investigations on zeolitic faujasite/benzene host/guest systems (Si/Al = 2.43 and ≈ 200) by using combined powder diffraction, adsorption calorimetry and molecular mechanics simulations

“…Neutron powder diffraction [4] and computational methods [5] show that the ideal cation distribution in anhydrous NaY (Si/Al = 2.43) is 8NaI (in the D6R hexagonal prisms, half-populated 16c positions) +16 NaI′ (in the betacages, half-populated 32e positions) +32 Na (in the alpha-cages close to S6R, fully populated 32e positions). Concerning NaY [4,[6][7][8][9][10][11][12][13] and other cationexchanged FAU [14][15][16][17][18][19], or deluminated Y (DAY or US-Y) [20][21][22], many experimental and theoretical work [23-27 and many references therein] describing the state of benzene molecules sorbed in these materials are reported in the literature. Nevertheless, there are still some conflicting results concerning the benzene and/or cation distributions, the adsorption heats and the sorption capacities of benzene in NaY and DAY faujasites.…”