A common algae commercially grown to make fish food holds promise as a source for both biodiesel and jet fuel, according to a new study published in the journal Energy & Fuels.
The researchers, led by Greg O’Neil of Western Washington University in the US and Chris Reddy of Woods Hole Oceanographic Institution, exploited an untapped class of chemical compounds to synthesise two different fuel products from a single algae.
Greg O’Neil said: “It’s novel. It’s far from a cost-competitive product at this stage, but it’s an interesting new strategy for making renewable fuel from algae.”
Algae contains fatty acids that can be converted into biodiesel molecules. In this study, Isochrysis algae was used because it can be grown in large batches to make fish food and it produces fats called alkenones, thought to be a potential fuel source.
Alkenones have a unique ability to change their structure in response to water temperature, providing oceanographers with a biomarker to extrapolate past sea surface temperatures.
The researchers first made biodiesel from the FAMEs in Isochrysis. Then they had to devise a method to separate the FAMEs and alkenones in order to achieve a free-flowing fuel.
Alkenones have long chains of 37 to 39 carbons and are too big to be used for jet fuel so the researchers broke them down into shorter carbon chains which are small enough to use for jet fuel.
Now the scientists want to try to produce larger quantities of the fuels from Isochrysis, but they are also exploring additional co-products from the algae.
The research was funded by the National Science Foundation, the Massachusetts Clean Energy Center, and Woods Hole Oceanographic Institution.
