THERMOPHYSICAL PROPERTIES OF NON-EDIBLE VEGETABLE OIL AND DERIVED ETHYL BIODIESEL OBTAINED FROM CHRYSOPHYLLUM ALBIDUM KERNELS

Abstract

The aim of this study was to evaluate the thermophysical properties of vegetable oil and derived ethyl biodiesel obtained from Chrysophyllum albidum kernels. Extracted oil was ethyl-transesterified and the effect of temperature and pressure on the thermophysical properties such as density, kinematic viscosity and isothermal compressibility (KT) was investigated both on the vegetable oil and on the derived ethyl biodiesel. The fatty acid ethyl ester composition of the formulated biodiesel was also evaluated using gas chromatography-mass spectrometry (GC-MS). Results obtained indicated that the yield of oil extraction is 33.23±3.26%, m/m, with peroxide index of 10.46± 0.12meq O2/Kg-oil. This peroxide index indicated that the oil was not very suitable for feeding and may be subject to rapid oxidation. The main fatty acid ethyl esters in the oil are linoleate (21.22%), linolenate (25.62%), oleate (19.7%) and palmitate (15.98%). The kinematic viscosity values of the extracted oil varied between 12.08 and 88.65 cst, while those of the derived ethyl biodiesel varied between 2.75 and 10.36 cst for temperatures between 293.15 and 353K. The KT decreases with increasing pressure at constant temperature while it increases with temperature at constant pressure. Data from this study will be useful in the prediction of diesel engine performance and their real-time simulations.