Utilization of <em>Moringa oleifera</em> oil for biodiesel production: A systematic review

Abstract

A major energy challenge currently is the depletion of global oil reserves which is gradually resulting in the decline of conventional diesel production. Several alternative fuels and renewable energy sources have been proffered with biodiesel constituting a promising option. Biodiesel has garnered increasing attention because it is renewable, biodegradable, non-toxic, and it is characterized by low carbon monoxide particulate and hydrocarbon emissions compared to the conventional diesel. In recent times, several scientific writings have documented the utilization of Moringa oleifera as feed stock for biodiesel production. Moringa oleifera (horseradish) is a multipurpose tree species and one of the most widely cultivated crops in tropical and sub-tropical areas of the globe. Databases used for this review include Google Scholar, Scopus, WorldCat.org, Microsoft Academic and Science Direct. A total of 216 articles were retrieved and 18 studies were ultimately retained after qualitative analysis. The analytic output shows the seed oil has favorable characteristics for use as biodiesel. The fatty acid composition of the oil makes it suitable for both edible and non-edible applications. Also, the percentage of oleic acid (70%) in Moringa oil is quite high compared to other crops which possess about 40% oleic acid. Moringa seed oil exhibit a high oxidative stability and its thermal stability exceeds other oil crops like sunflower oil, soybean oil amongst others. Biodiesel produced from M. oleifera seed oil exhibit enhanced oxidative ability, high cloud point and a higher cetane number of approximately 67 than for most biodiesels. Moringa oleifera biodiesel can be stored for a long period of time and it is safe for transport.

Keywords

• <i>moringa oleifera</i>
• biodiesel
• biofuel
• alternative fuel
• renewable energy