The influence of the acidic properties of the support on the catalytic performances of supported SnO2 surfaces has been investigated. The acidic properties of low Sn loading catalysts (ca. 3 wt.%) prepared starting from ShCl4, 5 H2O precursor and supported on γ-Al2O3, MgO, SiO2, TiO2, and ZrO2 were characterized by ammonia adsorption microcalorimetry. The catalysts were tested in the NO reduction with ethylene under high oxygen partial pressure at very high space velocity (50.000 h-1). The catalysts prepared on the acidic supports (ZrO2, Al2O3 and TiO2) were the most active. For Sn-ZrO2 at 425°C, 47% conversion of 5000 ppm NO to N2 and 77% conversion of 5000 ppm of C2H4 to CO2 were obtained in presence of 9% O2. Based on the N2 yield, the following scale of activity was found: Sn-ZrO2 > Sn-TiO2 ≈ Sn-Al2O3 >> Sn-SiO2.
|Titolo:||Role of acidic sites in the de-NOx process on supported tin oxides|
GERVASINI, ANTONELLA (Ultimo)
|Settore Scientifico Disciplinare:||Settore CHIM/02 - Chimica Fisica|
|Data di pubblicazione:||2000|
|Tipologia:||Book Part (author)|
|Appare nelle tipologie:||03 - Contributo in volume|