Effect of post-synthesis treatment on the stability and surface properties of MCM-48 silicas

Anne Galarneau (1) , Marie-France Driole (1) , Carolina Petitto (1) , Bich Chiche (1) , Barbara Bonelli (2) , Marco Armandi (2) , Barbara Onida (2) , Edoardo Garrone (2) , Francesco Di Renzo (1) , François Fajula (1)

1 ICGM ICMMM - Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier
2 Dipartimento di Scienza dei Materiali e Ingegneria Chimica

The effect of post-synthesis hydrothermal treatments on MCM-48 has been studied by 29Si MAS-NMR and IR spectroscopies, X-ray diffraction, thermal gravimetry, and gas volumetry. Special attention has been given to the characterisation of the precursors before calcination and a method to evaluate the pore opening of MCM-48 from diffraction and volumetric data is given. The hydrothermal treatment does not affect the organisation of the cetyltrimethylammonium mesophase but extracts a fraction of the surfactant and increases the thickness of the silica wall. The lower area of the silica-surfactant interface after hydrothermal treatment brings about an improved stability of MCM-48 during calcination and allows the pore size of the precursor to be preserved in the calcined solid. After calcination, the hydrothermally treated samples are less prone to rehydrate and, as a consequence, their stability upon storage in moist atmosphere is dramatically improved.

Domaines: Matériaux

Anne Galarneau, Marie-France Driole, Carolina Petitto, Bich Chiche, Barbara Bonelli, et al.. Effect of post-synthesis treatment on the stability and surface properties of MCM-48 silicas. Microporous and Mesoporous Materials, 2005, 83, pp.172-180. ⟨10.106/j.micromeso.2005.03.020⟩. ⟨hal-00380454⟩