Biodiesel Production, Analysis, and Combustion: An Across-the-Curriculum Laboratory

Abstract

Biofuels and biodiesels are a quickly expanding area of Green Chemistry and consist of mixtures of fatty acid methyl esters (FAMEs) commonly produced from plant sources. This across-the-curriculum laboratory experiment is designed to involve students in General, Organic, and Physical Chemistry courses working toward a common goal: the synthesis, analysis, and combustion of biodiesel fuels produced from common vegetable oils (liquid coconut, solid coconut, canola, and corn oils). Working in teams of General Chemistry and Organic Chemistry students, the General Chemistry students produced a single FAME through a Fischer Esterification to produce the FAMEs present in the biodiesel, which was analyzed by gas chromatography (GC) and infrared (IR) spectroscopy. Organic Chemistry students produced a biodiesel from an unknown 50:50 mixture of two vegetable oils and used the FAME GC data to identify the two oils present in their biodiesel; each oil chosen has a novel FAME profile to aid in this identification, and students were able to effectively identify the two oils in their biodiesel. Finally, Physical Chemistry students performed bomb calorimetry with the biodiesels to determine their energy content and correlate this to the vegetable oils identified in the mixture. The experiments, performed during the same week of the academic term, which we term as “Biofuels Week”, allow students to take part in the interdisciplinary nature of chemical research and experience the entire experiment as they progress through the Chemistry major and aim to foster community in the Chemistry Department at Knox College though a common goal: the production, analysis, and combustion of a biodiesel fuel.