Gas phase glycerol dehydration to acrolein using supported silicotungstic acid catalyst

Abstract

The gas phase dehydration of glycerol to acrolein over a series of supported silicotungstic acid (HSiW) on γ-Al2O3 nanoparticle (W10-Al, W20-Al, W30-Al and W40-Al) has been investigated. The catalysts were characterized by temperature programmed desorption, nitrogen adsorption–desorption, thermogravimetric analysis, X-ray diffraction, field-emission scanning electron microscopy and energy dispersive X-ray techniques. The large pore diameters (>21 nm) of the prepared catalysts alleviated the coke deposition effect. The acidity of the samples increased from 2 to 2.6 mmol/g.cat by varying HSiW loadings from 10 to 40 wt.% on γ-Al2O3 nanoparticle. The highest acrolein yield achieved was 74.1% at 94% glycerol conversion over W20-Al catalyst for 10 wt% glycerol feed concentration and 300 ˚C reaction temperature in 3 hours. The combined physicochemical characteristics of W20-Al made it more superior compared with other samples in the current study.