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Acetic Acid Ketonization over Fe₃O₄/SiO₂ for Pyrolysis Bio-Oil Upgrading.

ABSTRACT: A family of silica-supported, magnetite nanoparticle catalysts was synthesised and investigated for continuous-flow acetic acid ketonisation as a model pyrolysis bio-oil upgrading reaction. The physico-chemical properties of Fe₃O₄/SiO₂ catalysts were characterised by using high-resolution transmission electron microscopy, X-ray absorption spectroscopy, X-ray photo-electron spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, thermogravimetric analysis and porosimetry. The acid site densities were inversely proportional to the Fe₃O₄ particle size, although the acid strength and Lewis character were size-invariant, and correlated with the specific activity for the vapour-phase acetic ketonisation to acetone. A constant activation energy (∼110 kJ mol^-1), turnover frequency (∼13 h^-1) and selectivity to acetone of 60 % were observed for ketonisation across the catalyst series, which implies that Fe₃O₄ is the principal active component of Red Mud waste.

SUBMITTER: Bennett JA

PROVIDER: S-EPMC5434921 | biostudies-literature |

REPOSITORIES: biostudies-literature

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