Useful Products from Microalgae: Case Study of Ruai Wastewater Treatment Plant in Nairobi.
Journal of Kenya Chemical Society. 9(1):15-34. Abstract
Microalgae has had a number of applications. This study explores the formation of biodiesel from lipids and
formation of charred biomass fuel from the algae species found at Ruai Wastewater facility at Ruai, Nairobi. The
resulting biomass after solvent extraction was carbonized and the gross calorific value determined using a constant
volume bomb calorimeter. The bio-oil obtained from the algae was transesterified and the calorific value
determined. In one of the cases, carbon dioxide was bubbled through fresh algae from the waste water facility and
the biodiesel from this sample which was later sun-dried, crushed, then subjected to solvent extraction and
subsequent transesterification had the highest calorific value of 27,620 KJ/g compared to 22,758KJ/g in algae
sample which was not subjected to such a treatment. In the case of the charred biomass fuel, the gross calorific
value was found to be approx 23,132 KJ/g which makes it a medium calorific value fuel. GC-MS analysis was
performed on one of the transesterification samples and methyl esters of the isolated fatty acids were identified as
methyl esters of polyunsaturated fatty acid α-linolenic acid (18:3, n-3; ALA), Hexadecanoic acid and cis-9-hexadecenoic acid. In addition an alkane heptadecane was also isolated. This study shows that algae, which is
present in many water systems in Kenya can be used as a valuable source of fatty acids that are taken in diet by
animals and humans thus building a healthy nation.
Keywords: Microalgae, transesterification, biodiesel