Quality assessment of biodiesels from <i>Lophira Lanceolata</i> and <i>Ziziphus Mauritiana Seed</i> oils

Abstract

The purpose of this study was to produce and characterize biodiesels obtained from seeds of Lophira Lanceolata and Ziziphus Mauritiana. Oils were extracted from the seeds using soxhlet extractor with petroleum ether, transesterified using alkali hydrolysis (methanol/ethanol) to obtain biodiesels. Lophira and Ziziphus oils were transesterified under the following conditions: ethanol/methanol/oil molar ratio (6:1), potassium hydroxide catalyst (1.0%wt), temperature (55oC) and mixing intensity of 300rpm.The oils and alkyl esters produced were studied for physicochemical and fuel properties. Oil yields were determined and alkyl ester yields were measured using GC-MS method. The results showed percentage oil yields of 34.0±0.33% and 36.0±0.44% for Ziziphus and Lophira respectively. Some important fuel parameters investigated include; kinematic viscosity, acid value, pour point, ash content, sulphur content as well as some of crude lipid’s properties determined complied with ASTM standard specifications. Analysis of alkyl esters showed that methyl-9-octadecenoate (72.26%) and methyl eicosanoate (13.02%) as the predominant esters, while methyl hexadecanoate (78.34%) and methyl docosanoate (10.0%) are the most dominant esters for Lophira and Ziziphus biodiesels respectively. The results suggest that, oils from seeds of Lophira and Ziziphus exhibited some properties that make them suitable for biodiesel production.

Keywords: Lophira lanceolata and Ziziphus mauritiana Seed Oils, Lipid Yield, Transesterification,