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This work studies 2 wt% Pt catalysts. The support is a SiO 2 -C composite whose main features are a high specific surface due to its mesoporosity, a higher thermal stability than the C support, and the absence of surface acid sites which could promote the dehydration reactions that produce coke precursors. The Pt/SiO 2 -C catalyst has very small metallic particles (d va ¼ 1.37 nm) that favor the CeC bond cleavage reactions which allow obtaining total gas conversion at 450 C. With this catalyst, it is possible to obtain high yields to H 2 , between 4 and 5, which indicates that the active sites promote the WGS reaction, even with glycerol concentrations of 30 and 50%. Pt/SiO 2 -C is a very stable catalyst since it loses only 10% of its initial activity after 66 h on stream and is resistant to sintering and coke deposition.

To understand the complexity of the reactions involved in the steam reforming of glycerol and with the aim of identifying the contribution of C-C and C-O bonds cleavage, in this work we have studied the steam reforming of C3 alcohols simpler than glycerol such as 1-propanol, 2-propanol, 1,2-propanediol and 1,3-propanediol. A Pt/SiO 2 catalyst was employed and were studied the conversion and the product distribution for each alcohol. It was possible to determine the absence of C-O and C-C bonds cleavage in a secondary alcohol such as 2-propanol and 1,2 propanediol. The presence of reaction intermediates with an aldehyde function, deactivates the catalyst due to their strong adsorption on the metal site, moreover, the presence of hydroxyl-aldehydes promotes the C-C bonds cleavage favoring the gas production. The reaction pathway from glycerol to acetol by cleavage C-O bonding or dehydration on metal site is responsible for the subsequent reactions leading to deactivation.The main reaction pathway to obtain gaseous products from glycerol reforming involve C-C bonds cleavage of primary alcohols such as 2,3-dihydroxypropanal, 1,2-ethanediol and 2-hydroxyethanal. In order to confirm the proposed reaction pathways, steam reforming of ethylene glycol was performed, identifying this compound as primary intermediates to obtain gaseous products from glycerol.