TY - JOUR
T1 - Influence of surface acidity/basicity of selected metal oxide catalysts and reaction atmospheres on the ketonisation of propionic acid to produce 3-pentanone as a liquid biofuel precursor
AU - Hart, Abarasi
AU - Patel, Himanshu
AU - Yildirir, Eyup
AU - Onwudili, Jude
N1 - Copyright © 2025 The Authors. Published by Elsevier Ltd. This is an open access article distributed under the terms of the Creative Commons CC-BY license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
PY - 2025/5/6
Y1 - 2025/5/6
N2 - Defossilisation of the transportation sector can be achieved via the conversion of renewable biomass into drop-in liquid hydrocarbon-rich fuels. Bio-oils from the pyrolysis of lignocellulosic biomass contain significant proportion of carboxylic acids, which can be upgraded to liquid fuel range precursors via C-C coupling e.g. via ketonisation. In this present study, ZrO2, SiO2, and SiO2–ZrO2 were synthesised and used for the ketonisation of propionic acid to 3-pentanone, in a stirred 100 mL batch reactor between 300 ᵒC and 400 ᵒC under 10 bar pressure of nitrogen or hydrogen. The order of ketonisation activity by the catalysts was: ZrO2 > SiO2–ZrO2 > SiO2 under both nitrogen and hydrogen atmospheres, based on their different surface acidity/basicity properties. Under nitrogen, ZrO2 catalyst showed high activity and selectivity towards 3-pentanone with the highest yield of 70.3% at 350 ᵒC. Interestingly, the catalyst gave 12.2% higher yield of 3-pentanone under hydrogen than under nitrogen. This indicated positive influence of hydrogen towards the ketonisation reaction, possibly by preventing formation of intermediates and thus enhancing catalyst stability. Preliminary tests involving mixtures of propionic acid, and a bio-oil sample shows that ZrO2 was still selective toward ketonisation in the presence of other classes of compounds in bio-oils.
AB - Defossilisation of the transportation sector can be achieved via the conversion of renewable biomass into drop-in liquid hydrocarbon-rich fuels. Bio-oils from the pyrolysis of lignocellulosic biomass contain significant proportion of carboxylic acids, which can be upgraded to liquid fuel range precursors via C-C coupling e.g. via ketonisation. In this present study, ZrO2, SiO2, and SiO2–ZrO2 were synthesised and used for the ketonisation of propionic acid to 3-pentanone, in a stirred 100 mL batch reactor between 300 ᵒC and 400 ᵒC under 10 bar pressure of nitrogen or hydrogen. The order of ketonisation activity by the catalysts was: ZrO2 > SiO2–ZrO2 > SiO2 under both nitrogen and hydrogen atmospheres, based on their different surface acidity/basicity properties. Under nitrogen, ZrO2 catalyst showed high activity and selectivity towards 3-pentanone with the highest yield of 70.3% at 350 ᵒC. Interestingly, the catalyst gave 12.2% higher yield of 3-pentanone under hydrogen than under nitrogen. This indicated positive influence of hydrogen towards the ketonisation reaction, possibly by preventing formation of intermediates and thus enhancing catalyst stability. Preliminary tests involving mixtures of propionic acid, and a bio-oil sample shows that ZrO2 was still selective toward ketonisation in the presence of other classes of compounds in bio-oils.
UR - https://www.sciencedirect.com/science/article/pii/S0960148125010481?via%3Dihub
U2 - 10.1016/j.renene.2025.123386
DO - 10.1016/j.renene.2025.123386
M3 - Article
SN - 0960-1481
VL - 250
JO - Renewable Energy
JF - Renewable Energy
M1 - 123386
ER -