The physicochemical properties of algal biodiesel are similar to
those of petro–diesel fuels. The viscosity of algal oil wa
35.51 mm2
/s (Table 1). The viscosity of algal oil highly decrease
after transesterification process. The conversion of triglyceride
into ME through the transesterification process reduces the viscos
ity by a factor of about eight. As an oil temperature increases it
viscosity decreases (Demirbas, 2008). The algal biodiesel viscosity
was found to be 4.35 mm2
/s.
Density is an important property mainly in combustion system
because it influences the efficiency of atomization. Algal biodiese
density was 878.47 kg/m3
. It is known that biodiesel density
mainly depends on its alkyl esters content and the remained quan
tity of alcohol.
The flash point of the E. compressa algal biodiesel was measured
as 166 C. In fact, flash point strictly corresponds to the amount o
methanol and the viscosity correlates with the content of unre
acted triglycerides. The flash point values of biodiesel are signifi
cantly lower than those of respective oils (Demirbas, 2009). High
values of flash point decrease the risk off fire which is safe fo
transport purpose, and this circumstance represents an advantag
of biodiesel in relation to petro–diesel (Atadashi et al., 2010).