Biodiesel production from Halamphora coffeaeformis microalga oil by supercritical ethanol transesterification

HEGEL, PABLO E.; MARTÍN, LUCAS A.; POPOVICH, CECILIA A.; DAMIANI, CECILIA; LEONARDI, PATRICIA I.

CHEMICAL ENGINEERING AND PROCESSING

ELSEVIER SCIENCE SA

Año: 2019 vol. 145

0255-2701

Some microalga species have been suggested as potential biomass feedstock for biofuel production. In this work we studied the biodiesel production from the marine diatom Halamphora coffeaeformis. This species grows in seawater making large-scale cultivation advantageous. Moreover, sustainable biofuel production in future biorefineries requiresthe implementation of low cost technologies that employ renewable solvents. Thus, the goal of this work was to evaluate ethanol usage as extraction solvent and reaction medium for biodiesel production from H. coffeaeformis. A bio-oil extraction was carried out comparing ethanol and n-hexane to investigate the performance of ethanol withrespect to a conventional solvent used in the extraction of vegetable oils. Then, a free-catalyst supercritical ethanol transesterification of the extracted oils was carried out to obtain biodiesel. In general, ethanol was more efficient than n-hexane to perform the extraction. The supercritical processing of crude lipids extracted with ethanol as solvent produced up to 15.9 wt.% of biodiesel respect to dried biomass processed. Comparable biodiesel yields were obtained using non-renewable organic solvents and a conventional catalytic technology. Ethanol extraction and subsequent supercritical transesterification of H. coffeaeformis oil proved to be a feasible and environmental friendly technology for the production of biodiesel.