Steam-stable aluminosilicate

Figure 3.9 Schematic of the process used by Pinnavaia et al. for the preparation of steam-stable aluminosilicate nanostructures assembled from zeolite seeds, (a) Nanosize zeolites (zeolite seeds) (b) zeolite seeds assembling around the surfactant (CTAB) (c) assembled structure and,...

Y. Liu, W. Zhang, and TJ. Pinnavaia, Steam-stable Aluminosilicate Mesostructures assembled from Zeolite Type Y Seeds. J. Am. Chem. Soc., 2000, 122, 8791-8792. 

P-06 - Steam - stable aluminosilicate MSU-S mesostructures assembled from zeolite seeds... 

The hydrothermal stability and acidity of aluminosilicate mesostructures can be improved substantially through the surfactant - directed assembly of protozeolitic aluminosilicate nanoclusters that normally nucleate (seed) the formation of microporous zeolites. Our results indicate that zeolite type Y, Beta, and ZSM-5 seeds are particularly effective at forming steam stable aluminosilicate mesostructures, which we generally denoted as MSU-S. 

Y. Liu, W.Z. Zhang, and T.J. Pinnavaia, Steam-stable MSU-S Aluminosilicate Mesostruc-tures Assembled from Zeolite ZSM-5 and Zeolite Beta Seeds. Angew. Chem., Int. Ed., 2001, 40, 1255-1258. 

Strong acidic and high temperature hydrothermally stable mesoporous aluminosilicates with well-ordered hexagonal structure (MAS-5) have been successfully synthesized from assembly of pre-formed aluminosilicate precursors with cetyltrimethylammonium bromide (CTAB) surfactant. The MAS-5 shows extraordinary stability both in boiling water (over 300 h) and in steam (800°C for 2 h). Temperature programmed desorption of NH3 shows that acidic strength of MAS-5 is much higher than that of MCM-41. 

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