Biodiesel purification by solvent-aided crystallization using n-hexane as solvent

Biodiesel purification by solvent-aided crystallization using n-hexane as solvent

WAN NUR AISYAH Wan Osman, HATEEM Feroze, SHAFIRAH Samsuri, EDUARD Hernandez Yanez

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Abstract. Biodiesel is a form of fuel that has a natural origin as it is derived from organic components such as vegetable oil and animal fats. However, biodiesel has to be purified based on the required biodiesel purity standards before it can be used as diesel fuel. This study focuses on a lab-based purification method which is solvent-aided crystallization (SAC) using a typical solvent used for oilseed extraction that is n-hexane. Response surface methodology was used to optimize the process parameters. The purified biodiesel was analyzed via GC-MS to determine its fatty acid methyl ester (FAME) content, reflecting the purity of the biodiesel. The effect of cooling temperature and the concentration of the solvent was studied. The highest purity was obtained at intermediate parameter levels; 12°C and 1.5 wt% of n-hexane. The predicted optimum process parameters within the experimental range were 9.924°C and 1.131 wt%, with FAME purity of 99.789%. The data was validated with an experimental run, and the FAME purity obtained was 99.88%, a 0.1% difference from the predicted value. The FAME purity obtained was above the biodiesel purity standards making this environmentally friendly process viable to be used on a much larger scale in the biodiesel industry.

Cooling Temperature, Fatty Acid Methyl Ester, Environmentally Friendly, Response Surface Methodology, Solvent Concentration

Published online 5/20/2023, 11 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: WAN NUR AISYAH Wan Osman, HATEEM Feroze, SHAFIRAH Samsuri, EDUARD Hernandez Yanez, Biodiesel purification by solvent-aided crystallization using n-hexane as solvent, Materials Research Proceedings, Vol. 29, pp 117-127, 2023


The article was published as article 15 of the book Sustainable Processes and Clean Energy Transition

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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