Preparation and characterization of mesoporous molecular sives containing Al, Fe or Zn

Silica M41S type materials have been prepared starting from the mixture: 0.29 Na2O:0.12 CTABr:1 SiO2:100 H20 using water-glass as silica source. Syntheses were carried out at three different temperatures: 303, 343, and 413 K. The effect of the synthesis temperature on the nature of the products, the presence of AI, Fe or Zn, as well as the properties of the so-obtained materials and their thermal stability were studied. XRD, N2 adsorption. FTIR and NMR techniques were used for the characterization of the products. The adopted procedure enables the synthesis of thermally stable hexagonal mesoporous materials from hydrogels with Si/AI ratios ≥ 10. The AI forms contain both Brønsted and Lewis acid sites, whereas the Fe forms only contain Lewis acidic sites. © 2001 Elsevier Science B.V. All rights reserved