Jatropha- Soybean Biodiesel Blends: A Signature Design with Optimum Low Temperature Properties and Oxidation Stability

With growing concerns brought by excessive usage and depletion of fossil fuels, the race for finding alternative energy as their substitutes is getting heated up. In the midst of this, biodiesel has gained popularity as a renewable, environmental friendly alternative. Mono-alkyl esters of long chain fatty acids are called biodiesel. These esters can be obtained from vegetable oils by transesterification with alcohol. Despite its importance, biodiesel, mainly made from edible oils, causes an imbalance between the utilization of energy resources and food consumption. Hence, exploring non-edible seed oils as biodiesel raw materials seem feasible without significantly affecting the global food economy. In the present study, blends of Jatropha and Soybean biodiesel have been explored to determine the optimum mix, achieving better low temperature properties, with improved oxidation stability. A two-step process consisting of pre-esterification and transesterification was developed to produce biodiesel from crude Jatropha curcas L. oil and Soybean. The process was carried out at optimized set of conditions: methanol/oil molar ratio (6:1), sodium methoxide catalyst concentration (1.00 wt%), temperature (65oC) and mixing intensity (600 rpm). The physicochemical properties showed that the methyl esters contained low moisture level (<150 ppm) and acid value (<0.2 mg KOH/ mg-oil) respectively. Characterization of the fatty acid methyl esters (FAMEs) was accomplished by gas-chromatography. The fuel properties of the biodiesel blends produced were found to be within the standards specifications of ASTM D 6751 and EN 14214.