Production, Characterization and Performance Studies of Coconut Testa Biodiesel

Abstract

In the present work, coconut testa oil, the oil extracted from coconut testa (the outer brownish layer over the kernel of coconut flesh) is explored as feedstock for biodiesel production and a comparative study on the properties and performance of the developed, coconut testa biodiesel (CTBD) and commercial diesel fuel is presented. The biodiesel is produced from the coconut testa oil feedstock through the transesterification process. The evaluated properties showed that the developed CTBD possesses all the required property values as specified by ASTM and other standards for biodiesel. The density of the CTBD is approximately equal to that of diesel and the cetane number is about 26% more than that of diesel fuel. The heat value of the CTBD is about 10% less than that of diesel indicating the requirement of more fuel to be injected for the same amount of torque that obtained with diesel fuel. The biodiesel possesses low iodine and acid values and is hence capable to inhibit corrosion and provide good storage life without degradation The performance test of the compression ignition (CI) engine fuelled with the developed biodiesel (without diesel blend) revealed that all the performance characteristics are either comparable to diesel or marginally better than that of diesel fuel. With regard to emission, other than NOx concentration, all the constituents are either similar or more environment-friendly compared to that of diesel. The study confirms that the developed CTBD is a potential alternate fuel with the capability to fuel CI engines without diesel blending.

Keywords: coconut testa oil, biodiesel, coconut testa biodiesel, transesterification, emission, cetane number