Porous Silicon Nitride Materials as Basic Catalysts

✍ Scribed by D. Hullmann; G. Wendt; G. Ziegenbalg

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 169 KB
• Volume: 24
• Category: Article
• ISSN: 0930-7516
• DOI: 10.1002/1521-4125(200102)24:2<147::aid-ceat147>3.0.co;2-c

✦ Synopsis

Silicon nitride powders characterized by a high specific surface area were prepared by gas-phase ammonolysis of tetrachlorosilane. The compositions as well as the structural and textural properties of the materials were varied by the reaction conditions and the aftertreatment of the synthesis products. The Knoevenagel condensation of benzaldehyde and malonitrile served as a test reaction to characterize the catalytic properties of the materials. The experiments showed that amorphous silicon nitride powders have better catalytic properties than high surface magnesium oxide. However, treatment of the amorphous silicon nitride powders with water leads to a loss of nitrogen as ammonia and a decrease in the resulting catalytic activity.