Gas-phase conversion of glycerol over mixed metal oxide catalysts

Catalysis in Industry 03/2011; 3(1):70-75. DOI: 10.1134/S2070050411010132

ABSTRACT A series of aluminophosphates (APO) catalysts with Ce, Cu, Cr, Fe, Mn, Mo, V, and W oxide loading at a constant ratio M: Al = 1: 10 and PO4: Al = 1: 12 were prepared and characterized by N2 physisorption, XRD and NH3-TPD. Gas-phase dehydration of glycerol to produce acrolein and acetol was investigated at 280°C in presence of water. Conversion
and product distribution depended on the intrinsic acidity and the type of transition metal oxide. Best selectivity to acrolein
(52–58%) was obtained for W- und Mo-APO catalysts. Cr-, Mn- and W- oxide containing catalysts enhanced the formation of phenol,
acetaldehyde and CO
. The catalysts containing V- and Fe-oxide promoted the formation of allyl alcohol. All catalysts showed long term stability,
which can be attributed to the redox ability of the metal oxides that enhances the removal of coke deposits. The investigated
catalyst a specially W-APO and Mo-APO can be recommended for further controlled trials on a pilot plant for selective conversion
of water solution of glycerol to acrolein and/or acetol.

Keywordstransition metal oxide–Al2O3-PO4

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