Physical chemistry of hydrated molecular sieves: Combined study of theoretical and experimental approaches. Understanding and outlooks of hydration mechanism of aluminophosphates

G. Poulet , P. Sautet , A. Tuel (1)

1 IRC - Institut de recherches sur la catalyse

Microporous aluminophosphates AlPO4-n have drawn considerable attention due to their potential to act as heterogeneous catalysts and mol. sieves. Hydration of these compds. usually modifies the coordination of framework aluminum species and causes a reversible structure deformation. Here, a combined use of exptl. tools and of a theor. approach based on the d. functional theory (DFT) contributes to a better knowledge of the interactions between water mol. and AlPO4-n frameworks. Information on the behavior of water in the pores has been obtained from the study of a model compd., AlPO4-34. A dehydration/rehydration mechanism has been proposed as well as a partially hydrated phase, in agreement with solid-state NMR and X-ray diffraction results. Then, a complete exptl. study (IR spectroscopy, X-ray diffraction, thermal anal., NMR) has been supplemented by static or dynamic theor. approaches to get information on the calcined rehydrated AlPO4-18 phase

Domaines: Catalyse

G. Poulet, P. Sautet, A. Tuel. Physical chemistry of hydrated molecular sieves: Combined study of theoretical and experimental approaches. Understanding and outlooks of hydration mechanism of aluminophosphates. L'Actualité Chimique, 2005, 282, pp.18-26. ⟨hal-00016958⟩