Currently, ethyl esters (algae oil) (Khan et al., 2009).

Currently, more than 95% of world’s biofuel production is produced from edible oils (Ahmed et al., 2014; Gui et al., 2008). However, producing biofuels from edible oil sources has received criticism from several nongovernmental organizations worldwide (Sanjid et al., 2013; Tan et al., 2011). The extensive use of edible oils might lead to some negative impacts such as starvation and higher food prices in developing countries (Balat, 2011b; Sanjid et al., 2014). Therefore, using non-edible vegetable oils as biofuel which are not suitable for human food can replace the current dependence on the edible oil source. Many of the researchers agree that non-edible sources are the suitable alternative to edible feedstock for algae oil production (Chhetri et al., 2008). Hence, the recent focus is to find nonedible oil feedstock for algae oil production. Plant oils or glycerides have higher viscosity and density than the diesel fuel, due to their long hydrocarbon chains. Their direct use in diesel engines would adversely affect power and emission levels caused by their poor ignition. Therefore, to modify the structure of plant oils as fuels applicable to diesel engines, their triglycerides are converted into a algae oil fuel through the transesterification process by a simple alcohol and a base/acid catalyst (Asakuma et al., 2009; Ferella et al., 2010). Algae oils are Fatty Acid Alkyl Esters (FAAEs) produced from glycerol Terri esters, glycerol di esters, Free Fatty Acids (FFAs) and phospholipids. Plant and animal oils are the main sources of these acids. By another definition, the fuel derived from triglycerides is called algae oil, where 3 fatty acid molecules react with glycerol by establishing ester bonds in the presence of ethanol. With glycerol being thus released, the fatty acids are turned into methyl esters or ethyl esters (algae oil) (Khan et al., 2009). Algae oil is known as the best alternative for diesel fuel due to its following advantages (Nurun Nabi et al., 2006; Martins et al., 2010; Rashid et al., 2011): 1. Algae oil decomposes four times faster than diesel due to its high oxygen content. After 28 days, 77 to 89% of algae oil is decomposed, whereas only 18% of the diesel fuel decomposes in the same period.2. Algae oil is renewable, and countries such as European Union (EU) member states predicted a 12% target (from total energy demand) for algae oil by 2010.3. Algae oil has a satisfactory energy balance.