The present study introduced an integrated method for the production of biodiesel from microalgal oil. Heterotrophic growth of
Chlorella protothecoides resulted in the accumulation of high lipid content (55%) in cells. Large amount of microalgal oil was effi-
ciently extracted from these heterotrophic cells by using n-hexane. Biodiesel comparable to conventional diesel was obtained from
heterotrophic microalgal oil by acidic transesterification. The best process combination was 100% catalyst quantity (based on oil
weight) with 56:1 molar ratio of methanol to oil at temperature of 30 C, which reduced product specific gravity from an initial value
of 0.912 to a final value of 0.8637 in about 4 h of reaction time. The results suggested that the new process, which combined bioengineering
and transesterification, was a feasible and effective method for the production of high quality biodiesel from microalgal oil.
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