2D–3D structures: The hydrothermal transformation of a layered sodium silicate, Na-RUB-18, into mordenite zeolite

• Na-RUB-18 was used as precursor for mordenite.
• Na-RUB-18 lamella were activated by bonding to aluminum ions.
• The reaction occurs in 7–14 days depending on the Al source.
• No structure directing agent was added in the reaction mixture.

The synthesis of the high-silica mordenite zeolite by hydrothermal transformation of the Na-RUB-18 layered silicate was conducted by the addition of Al[OCH(CH3)2]3 or Na2Al2O4 into the gel after 7 days of hydrothermal treatment of a non-aluminum gel. Extensive characterization showed that the samples were obtained in good crystallinity in periods varying from 7 to 14 days after the addition of the aluminum source when Al[OCH(CH3)2]3 was used and after 14 days for Na2Al2O4. Results of 29Si and 27Al NMR suggest a gradual transformation of Na-RUB-18 into MOR by the appearance of signals which correspond to silicon atoms coordinated to 1and 2 Al and one signal corresponding to tetrahedrally coordinated aluminum atoms, both nonexistent in Na-RUB-18.

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