(315c) Sub and Supercritical Conversion of Kirchneriella Algal Biomass into Biocrude Oil

Sub and supercritical water technology utilizes wet biomass as feedstock to produce liquid fuels. Water at elevated temperature and pressure exhibit extraordinary solvent properties. Here, water acts as reactant as well as reaction medium in performing various complex chemical reactions. Algal biomass was an interesting feedstock for producing biofuel via sub and supercritical technology due to their high water content. We investigated the potential of microalgae (Kirchneriella sp.) for biofuel production. Several process parameters such as reaction temperature, pressure, time and solid loading were studied. Biocrude oil yield of 45.5% was achieved at 300^oC, 30 min, 100 bar and 10% solids loading. Lower biocrude oil was produced at supercritical conditions (374^oC and 220 bar) compared to subcritical conditions due to intensive gasification at higher temperatures. The high heating values (HHV) of biocrude oil and bio-char were determined with a bomb calorimeter. The biocrude oils and water soluble organics were Analyzed using gas chromatography mass spectrometry (GC-MS) and calorimetrically. CHNS/O analyzer was used to determine the elemental composition of algae, biocrude and biochar samples.