Effect of Ta2O5 as a Support in Phosphotungstic Acid Catalysts for Vapor Phase Dehydration of Glycerol to Acrolein

Abstract

The Ta₂O₅ supported phosphotungstic acid (HPA) catalysts were investigated for vapor phase dehydration of glycerol to acrolein and materials were synthesized by impregnation method. The above HPA catalysts were characterized by Raman spectroscopy to identify the Keggin ion and temperature programmed desorption of ammonia to explore the acidity of the catalysts. The findings of Raman spectra shows that the Keggin ion of heteropolyacid intact with support. NH₃-TPD results confirm that the acidity of the catalyst increases with incline in HPA loading. The Ta₂O₅ supported catalysts have shown remarkable catalytic performance compared to zirconia and titania supported catalysts during the dehydration of glycerol to acrolein reaction. 

Keywords: HPA, Ta₂O₅, glycerol, acrolein, acidity