Abstract:
In the present work, biodiesel was produced from watermelon waste oil by the transesterification process. A
definitive screening design was used to investigate the effect of transesterification parameters such as catalyst
concentration (4 − 10 %), methanol-to-oil ratio (2 − 10 mol/mol) and reaction temperature (46-60◦C). The
quadratic regression analysis was used to predict the yield of biodiesel. It is found that the optimum catalyst
concentration, methanol-to-oil molar ratio and reaction temperature are 5.51%, 5.77:1 and 60◦C, respectively,
resulting in a 96.763% yield of methyl esters, which is in excellent confirmation with the predicted value. Ac cording to the results, all variables had a significant effect on the yield of biodiesel. The physicochemical
property of the extracted watermelon waste oil and produced biodiesel using optimum process parameters was
analyzed. The results revealed that the extracted oil and produced biodiesel met the requirements of ASTM and
EN14214 (European committee for standardization) standard methods. Oleic acid and Linoleic acid were
detected to be the dominant unsaturated fatty acids; while palmitic acid was found to be the highest amount of
saturated fatty acid. It can be concluded that a definitive screening design for optimization of transesterification
reaction parameters is an effective way to boost the yield of biodiesel. In addition, this method significantly
reduces the number of experiments, which is important for a limited amount of raw materials. In general, the
finding of this work proposes that the watermelon waste oils seem to be a potential and alternative feedstock for
the production of biodiesel from waste materials.
