1. Biodiesel production Oil extraction A big deal!

2. Physical extraction mechanical crushing ultrasonic extraction ( create bubbles to break cell walls, always combined with enzymatic extraction )

3. Chemical extraction Chemical solvent (Benzene, ether, hexane) Super critical CO 2 (having properties of both a liquid and a gas)

4. Pyrolysis technologies Thermal degradation of the polymeric components of biomass LiquidcharGas Fast pyrolysis Moderate temperature(~500 ℃ ) short hot vapour residence time(<2s) 75% Mostly organics 12%13% Slow pyrolysis Low-moderate temperature, long residence times 30% Mostly water 35% Gasification High temperature (>800 ℃ ), long vapour residence time 5% tars10%85%

5. liquefaction High content of water often exists in microalgae after harvesting, which requires a great deal of energy to remove moisture in the algal cells in the period of pretreatment. It was reported that Dunaliella Tortiolecta cells with 78.4% water content converts to oils directly. The yield of oils reached 37% of the total organic matters. Dote et al. reported that B. braunii produced liquid oils at 57–64% of dry weight under the conditions of a N 2 pressure of 10 MPa at 300 ℃ in warm water and catalyzed by Na 2 CO 3.