Glycerol conversion in the presence of carbon dioxide on alumina supported nickel catalyst

•A potential route for glycerol valorization and CO2 sequestration was obtained.•The glycerol/nickel ratio affected the selectivity to different oxygenated compounds.•From 250 °C, the liquid product composition was complex.•CO2 conversion was only observed below 200 °C.•CO2 presence favored oxiranes, alcohols and esters formation.

The glycerol conversion in the presence of carbon dioxide was investigated on a Ni/γ-Al2O3 catalyst. The catalyst was characterized by XRD, TPR, BET, XPS, H2-TPD, DRIFTS and Raman. A catalyst preparation method using ethylene glycol and a reduction passivation procedure provided an active catalyst. For the different catalytic runs in a batch reactor, a higher formation of hydrocarbons, alcohols, ketones, and furans was observed when the mass of catalyst was increased. For temperatures below 200 °C, both glycerol and CO2 were converted, suggesting a potential route for glycerol valorization and CO2 sequestration, with the consequent production of oxirane, alcohols, ketones and carboxylic acids. For higher temperatures, there was the formation of a wide range of low yield products, with higher yields to ketones, alcohols and esters.

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