Extraction of Algal Oils From Wet Algae Under Subcritical Water Conditions

Extraction of biocrude from algal biomass was demonstrated with algal biomass containing more than 90% of water in biomass. This method offers potential solution for extraction of oil in less energy intensive way compared to other extraction methods. Conventional solvent extraction methods folch and Bligh & dyer are also performed and compared to subcritical water extraction in terms of extraction efficiency and energy expenses. With the help of design of experiments (DOE) effects of reaction parameters biomass loading, temperature and extraction time on extraction are studied and optimized. The purification of biocrude to produce clear algal oil was also performed through activated charcoal bed. The fatty acid composition of algal biomass and extracted biocrude are analyzed with GC-MS and FT-ICR. Thermogravimetric analysis (TGA) is performed to analyze the thermal behavior of biomass. TEM and SEM-EDS instruments have been used to determine the biomass topology and qualitative analysis of elemental composition.