In the previous study (Alptekin et al., 2012), optimum reaction
parameters were investigated to produce biodiesel from fleshing
oil in laboratory scale apparatus. Acid value of the fleshing oil used
in the previous study was 24.3 mg KOH g1 which corresponds to
FFA level of about 12.15%. FFA level of the feedstock was decreased
below 1% FFA level in the laboratory scale experiments by one step
pretreatment reaction. As seen in Table 1, the acid value of the
fleshing oil used in this study was 24.7 mg KOH g1. The pretreatment
reaction parameters determined in the laboratory experiments
were used in pilot scale biodiesel production because the
properties of the fleshing oil used in the laboratory experiments
were very close to those of the fleshing oil used in this study.
The pretreatment conditions for fleshing oil were 30:1 alcohol
molar ratio and 10% sulfuric acid based on FFA level of the fleshing
oil. In the calculations, the molecular weight of the FFA was calculated
to be the average molecular weight of the fatty acids in the
fleshing oil. The esterification process was repeated for two times
for the fleshing oil. The ingredient amounts used in the pretreatment
reactions for the fleshing oil were given in Table 3a.