Comparison of Cold Flow Properties Between Fatty Acid Methyl Esters and Fatty Acid Ethyl Esters

Biodiesel fuels are composed of the esters of fatty acid components of bio-based oils, such as canola oil, palm oil, poultry fat, other waste cooking oils, and many more. The alcohols used to convert these feedstocks into green fuels are typically methanol and ethanol, yielding fatty acid methyl esters (FAME) and fatty acid ethyl esters (FAEE), respectively.

Biodiesels have many characteristics that make them favorable in comparison to petrol-based fuels: renewability, carbon neutrality, lower sulfur emissions, biodegradability, and more. However, biodiesel fuels still have a few major shortfalls, including oxidative stability and cold flow properties, or operation at low temperatures. The latter shortcoming is the focus of this experiment.

Available literature on FAME biodiesel is much richer than FAEE biodiesel. FAEEs could potentially be quite valuable as biodiesel components, as ethanol can be renewably sourced, and pure FAEEs have lower cloud points than their corresponding FAME counterparts. Due to the shortage of FAEE data in literature, this experiment sought to establish a database of FAEE cold flow data, and draw comparisons between FAMEs and FAEEs.