Biofuel production potentiel from marine algae

Fossil fuels are the main sources of energy consumption, however, they raised concerns over their decreasing supply and heavy environmental impacts such as air pollution, greenhouse gases production, and global warming. Biofuels are renewable energy sources which produce much lower contamination and might be appropriate alternatives for fossil fuels. In this regard, micro-algal based fuels are important due to their high growth rate. They can be cultivated in arid areas, and utilize saltwater in small amounts. In addition, microalgae have higher carbon dioxide fixation rates in contrast to the terrestrial plants. Biodiesel and bioethanol are the most common algal biofuels which are appropriate alternatives to traditional diesel oil. Biodiesels are known as "neutral carbon" because their carbon dioxide emission to the air is significantly low. Optimizing the algal cultivation factors, in addition to improvements in harvesting and processing methods will result in a maximum yield of biofuel primary compounds such as lipids and sugars. The extracted oil from algae is used directly as a liquid fuel, and the remaining biomass is converted into bioethanol and biogas by anaerobic digestion/fermentation or used as fertilizer or animal feed. This review analyses different methods used for algal culture and biofuel production in recent years