Green production of biofuels from fish discards using supercritical Carbon Dioxide as the extraction solvent

Fishing discards and wastes have great potential as renewable energy sources of biofuel, biogas and bioactive molecules for a variety of applications. Fish oils have features resembling those of petroleum fuels, being a promising and eco-friendly alternative to fossil derivatives. Here we report a preliminary investigation of a green method of biofuel production from fishing discards, obtained by two trawl hauls in the South-Western Adriatic Sea. The method is based on the use of supercritical carbon dioxide (SC-CO2) as a green solvent for lipid oils extraction and subsequent conversion into fatty acid methyl esters (FAMEs) suitable as biodiesel. Experiments were carried out to optimize yields of lipid extracted oil by tuning SC-CO2 pressure, flow rates and temperature, with the best result of 10% (w/w) of fish oil extract recorded at 30 MPa, 50°C and 1 l/min SC-CO2 flow rate