KINETICS OF SELF-DIFFUSION OF WATER MOLECULES IN NATROLITE
A. V. Sabylinskii1, N. K. Moroz2, S. P. Gabuda2
1Shukhov Belgorod State Technological University, Belgorod, Russia 2Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: природные цеолиты, натролит, ЯМР H, кинетика самодиффузии HO, механизм диффузии, natural zeolites, natrolite, H NMR
, HO self-diffusion kinetics, diffusion mechanism
Abstract
Solid-state 1H NMR is applied to investigate the kinetics of diffusion of H2O molecules in the fibrous zeolite natrolite [Na2Al2Si3O10]×2H2O. It is found that the stepwise heating of the zeolite in air leads to the following pattern of molecular diffusion jumps: at first they increase in number and then decrease exponentially with time. Conducting such an experiment in an aqueous medium leads to the opposite effect. The results obtained confirm our previous suggestion about the importance of interstitial defects, or over-hydrated local states, in molecular diffusion.
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