Dawit Firemichael, Ahmed Hussen and Wendawke Abebe
ABSTRACT: Oil has been extracted from Cladophora green algae and then transesterfied to prepare biodiesel. Oil extraction was carried out using three techniques (Soxhlet, refluxing and shaker) and an average yield of 24 % of its dry weight was obtained.The amount of oil obtained by Soxhlet & refluxing didn’t show statistical significant difference. However in terms of extraction time refluxing is found to be much better than Soxhlet. The total oil extracted was transesterified using NaOH as a catalyst. The prepared biodiesel was evaluated against the standards set by American Society for Testing and Materials (ASTM) and European standards (EN). The resulting biodiesel was pure and showed excellent physical and chemical properties meeting international standards. Briefly,specific gravity, acid value, iodine value, ash content and calorific value of algae biodiesel were within the specification of ASTM and EN. The analysis of fatty acid methyl ester composition showed,62.96 % 9-octadecodenoic acid methyl ester, 26.98 % Hexadeconic acid methyl esterand 10.05 % Octadeconoic acid methyl ester.In an attempt to produce zero west biodiesel, two waste streams were combined to form glycerin pellet. The measured energy content of glycerin pellet was found to be comparable with fire wood. Therefore Cladophora green macro algae have a potential application for biodiesel and glycerin pellet production. The latter has the advantage of mitigating deforestation in developing countries.
Key words: Algae oil; biodiesel; transesterification; glycerin pellet