Hydrodeoxygenation of acrylic acid using MO^sub 2^C/Al^sub 2^O^sub 3

Hydrodeoxygenation of acrylic acid to propane on M02C/Al203 was investigated by temperature- programmed surface reaction and diffuse reflectance infrared Fourier transform spectroscopy. The obtained results imply that the reaction proceeds through a dehydration route where the cleavage of the C-O bond is favored leading to the formation of one water molecule, instead of the decarboxylation/decarbonylation (C-C cleavage) that occurs in noble metals and sulfide catalysts. Experimental results suggest that oxygen elimination occurs prior to the hydrogenation of double bond, which was confirmed by density functional theory calculations. The experimental and theoretical results allow to propose a reaction network in which the hydrogen preferentially attacks the carboxyl group instead of the double bond of acrylic acid to produce an intermediate that is transformed into propane.