Esterification of used vegetable oils using the heterogeneous WO₃/ZrO₂ catalyst for production of biodiesel

• Published in: Bioresource technology 2010, Vol.101 (1), p.S59-S61
• Main Authors: Park, Young-Moo, Lee, Joon Yeob, Chung, Sang-Ho, Park, In Seon, Lee, Seung-Yeon, Kim, Deog-Keun, Lee, Jin-Suk, Lee, Kwan-Young
• Format: Article
• Language: English
• Subjects: biodiesel; biomass; Catalysis; catalysts; Energy-Generating Resources; Esterification; fatty acid esters; fatty acid methyl esters; food wastes; free fatty acids; methanol; Oxides - chemistry; Plant Oils - metabolism; Refuse Disposal - methods; renewable energy sources; soybean oil; transesterification; Tungsten - chemistry; tungsten oxide; vegetable oil; zirconia; Zirconium - chemistry; zirconium oxide
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2009.04.025

Tungsten oxide zirconia, sulfated zirconia and Amberlyst-15 were examined as a catalyst for a conversion of used vegetable oils (VOs) to fatty acid methyl esters (FAMEs). Among them, tungsten oxide zirconia was a promising heterogeneous catalyst for the production of biodiesel fuels from used VOs because of high activity in the conversion over 93% and no leaching WO₃ in the esterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, stirring speed, WO₃ loading over ZrO₂ and reaction time, was carried out. The catalyst was characterized by BET, XRD, FT-IR, and NH₃-TPD. With increasing WO₃ loading over ZrO₂, the triclinic phase of WO₃ increased and the tetragonal phase of zirconia was clearly generated. The highest acid strength of 20wt% tungsten oxide zirconia catalyst was confirmed by NH₃-TPD analysis and the result was correlated to the highest catalytic activity of the esterification reaction.