Catalytic upgrading of pyrolytic oil using CeO2-ZrO2 mixed oxide catalysts

Abstract

Bio-oil produced from biomass is a mixture of oxygenated compounds including acids, alcohols, ketones, esters, ethers, aldehydes, phenols, and derivatives, as well as carbohydrates, and a large proportion (20–30 wt.%) of lignin-derived oligomers. One possible application of bio-oil being considered is converted to hydrogen by steam reforming. This thesis is to reports the development of catalyst for hydrogen production of steam reforming reaction over Ni supported on CeO₂-ZrO₂. Acetic acid, ethanol and acetone are used as a model of bio-oil. It was found that the Ni/Ce₀.₇₅Zr₀.₂₅O₂ exhibits an excellent activity for an acetic acid steam reforming comparing to Ni/MgO and Ni/Al₂O₃. This is due to good redox properties of Ce₀.₇₅Zr₀.₂₅O₂. Moreover, by adding potassium over Ni/Ce₀.₇₅Zr₀.₂₅O₂ catalyst is able to modify NiO phase from a rhombohedral to a cubic phase, resulting in the improvement of catalytic properties of the Ni/Ce0.₇₅Zr0.₂₅O₂ catalyst. The presence of K species, can also suppress carbon deposition. For the Co/Ce1-xZrxO₂ catalysts exhibit excellent activity for steam reforming of acetone. The catalytic steam reforming of acetone occurs on both mixed oxides supports and metal phases.