Mesoporous molecular sieves MCM-41 with incorporated structural aluminum (Al-MCM-41) of different Si/Al ratios (ranging from 3 to 100) were prepared using a modified hydrothermal method. Characterization using X-ray powder diffraction and nitrogen adsorption measurement showed that all these samples had typical XRD diffractogram of MCM-41, the adsorption isotherm of type Ⅳ and an uniform pore size distribution. The last feature reflects a highly ordered structure of pore arrays. Solid state ^2^7Al MAS NMR investigation showed further that even at high level of aluminum (x~A~l=0.303), the Al atoms could still be incorporated tetrahedrally in the MCM-41 structure. Based on the experimental results, the effects of aluminium content on the pore structure and the formation mechanism of Al-MCM-41 were discussed.

Key words: ALUMINIUM, X-RAY DIFFRACTION ANALYSIS, NITROGEN, ADSORPTION, STRUCTURE, CATALYTIC BEHAVIOUR