Title:
Oleic Acids Esterification on Microporous and Mesoporous Alumino-Silicate Catalysts: Acidity and Porosity Effect
Author(s):
Karakoulia, S.A., Marianou, A.A., Michailof, C.M., Sountourlis, M., Iliopoulou, E.F., Lappas, A.A.
Document(s):
Paper
Poster
Abstract:
Catalytic esterification of free fatty acids (FFA) is a key process for the production of biodiesel, an alternative fuel to petroleum diesel having less pollutant emissions. The current work presents the esterification of oleic acid, as a representative FFA, with C2 to C4 alcohols, using acid modified mesoporous silicas of MCM-41 type, while microporous zeolitic materials were also studied as heterogeneous catalysts. In the aspect of stability, alumina grafting was also applied. Hence, deposition of heteropolyacids (HPAs) on the surface of mesoporous supports was further performed in order to enhance Brönsted acidity. Concerning microporous materials, zeolites with various molar ratios of SiO2/Al2O3 (SAR) and different crystal types (MFI, BEA, MOR and FAU) were also tested, in order to study the correlation between catalysts’ activity and the respective structural, acidic and morphology characteristics. All synthesized materials were fully characterized using ICP-AES, XRD, N2 porosimetry and in-situ pyridine-FTIR. Screening of the above catalysts was applied for oleic acid esterification with ethanol (EtOH) in an autoclave reactor, at standard reaction conditions (150 °C, 60 min, molar ratio of oleic/EtOH= 1/6, weight ratio of oleic/catalyst=100). Highly dispersed active acid sites were found to favor conversion of oleic acid. Based on this finding, USY zeolite with SAR=60, having the lowest total acidity to total surface area ratio value, showed the best catalytic performance.
Keywords:
biodiesel, esterification, oleic acid, heterogenous catalysis, zeolites, HPA-modified mesoporous catalysts
Topic:
Biomass Conversion to Intermediate Bioenergy Carriers and Sustainable Biofuels
Subtopic:
Oil-based and renewable hydrocarbon biofuels
Event:
30th European Biomass Conference and Exhibition
Session:
5BV.6.9
Pages:
910 - 918
ISBN:
978-88-89407-22-6
Paper DOI:
10.5071/30thEUBCE2022-5BV.6.9
Price:
FREE
