Impact of the Zn source on the RSN-type zeolite formation

Ana Palčić , Bartłomiej M Szyja , Maja Mičetić , Tomaž Čendak , Mariame Akouche , Krunoslav Juraić , Marija Čargonja , Darko Mekterović , Vitomir Vušak , Valentin Valtchev (1)

1 LCS - Laboratoire catalyse et spectrochimie

Typical zeolite synthesis reaction mixture involves framework atom source, solvent, mineraliser, and structure directing agent. However, these components often have a dual function, and their impact on the nucleation/crystallization process is difficult to be established straightforwardly. The present study deals with the structure directing effect of zinc in the preparation of zincosilicate RUB-17 (RSN-type material). First, an attempt was made to introduce several other heteroatoms (Al, B, Ge, Mg, Li, Zr) into the RSN framework under the same reaction conditions as for Zn-RSN. Second, different Zn sources have been employed in order to study their impact on RUB-17 intermediates and the final product properties. The obtained series of samples were analysed by XRD, XRF, GISAXS, SEM, TEM, TG as well as by Raman, NMR, infrared and solid state UV/VIS spectroscopy. The physicochemical analysis of the obtained solids were complemented by the DFT modelling. The results show that RSNtype material can be solely prepared in the Zn-containing systems, where zinc plays a structure directing role besides its function as a framework cation. Namely, the lov-unit, a basic building unit of RSN framework, is formed at the very beginning of the crystallization no matter the zinc source employed. Yet, the differences in the crystallization of different system and relatively long time needed for full transformation of the precursor indicates there is some other limiting step that accounts for the formation of the zeolite.

Mots clés: zeolite synthesis; zinc; silicate; three-membered ring; structure directing; precursor

Domaines: Chimie

Ana Palčić, Bartłomiej M Szyja, Maja Mičetić, Tomaž Čendak, Mariame Akouche, et al.. Impact of the Zn source on the RSN-type zeolite formation. Inorganic Chemistry Frontiers, 2019, 6 (9), pp.2279-2290. ⟨10.1039/C9QI00433E⟩. ⟨hal-03034463⟩