Production of alternative fuel has attracted wide
attention during the past few years, due to the diminishing
petroleum reserves and environmental consequences of
exhaust gases from fossil diesel. In this context, biodiesel
which is characterized as a renewable, biodegradable, and
environment-friendly fuel is becoming a blooming area of
high concern. Biodiesel can be produced from macroalgae
because it contain considerable amount of lipid contents
(Hossain et al., 2008). In addition in heterotrophic
condition lipid content can be more in algae (Renaud &
Luong-Van, 2006). Pohl & Zurheide (1979) investigated
that lipids of some macroalgae (seaweeds) was reported to
be very high, up to 51% of total fatty acids.
The majority of biodiesel today is produced by alkalicatalyzed
(e.g., NaOH, KOH) transesterification with
methanol, which results in a relatively short reaction time
(Freedman et al., 1984). Vasudevan & Briggs (2008),
examined different biodiesel sources (edible and
nonedible), virgin oil versus waste oil, algae-based
biodiesel that is gaining increasing importance, role of
different catalysts including enzyme catalysts, and the
current state-of-the-art in biodiesel production. The
biodiesel esters were characterized for their physical and
fuel properties including density, viscosity, iodine value,
acid value, cloud value, pure point, gross heat of
combustion and volatility and fuel produces slightly lower
power and torque, and higher fuel consumption than No.
2 diesel fuel (Demirbas, 2008).
Biodiesel is better than diesel fuel in terms of sulfur
content, flash point, aromatic content and biodegradability
(Bala, 2006).