Surface acidity diagnosis and catalytic activity of AlSBA materials obtained by direct synthesis

The objective of this work is to give a characterization of aluminosilicate AlSBA materials in particular with respect to acidity and the nature of ac id sites. The number of acidic centers and the strength of these sites are determined by ammonia adsorption and temperature-programmed desorption (TPD ). The Bronsted acidity of AlSBA is also assessed by measuring the relative intensity of the laser-induced fluorescence (LIF) quinolinium ion band pea king at 390 nm when quinoline is adsorbed on the surface of the material. W hen Lewis acid sites are present, a complex formed between these sites and quinoline is observed. The AlSBA samples showed a high and durable activity in the cumene cracking. (C) 2001 Elsevier Science B.V. All rights reserved .