Investigation and optimization of bio-oil extraction from mixed Jatropha-Castor seeds using screw-pressing methodology

Abstract

The increasing global energy demand has led to the dominance of fossil fuels, but they also contribute to harmful emissions and global warming, and biofuels offer a promising alternative. This study aims to extract bio-oil from mixed Jatropha-Castor seeds as an alternative fuel, overcoming atomizing challenges with current biofuels through precise extraction methods. A comprehensive exploration of various extraction methods, including solvent, hydraulic, and screw pressing techniques, is undertaken. Special attention is given to optimizing the screw pressing method in terms of yield, energy and time consumption. In the realm of screw pressing, the oil yield is enhanced by elevating the extraction temperature and screw speed across all proportions. The yield showed a significant correlation with temperature, while speed significantly impacted energy and time consumption. The screw press method demonstrates considerable suitability for processing mixed Jatropha-Castor seeds in comparison to solvent and hydraulic methods. Quantitatively, the screw-pressing enhances the yield by 34.27–131.96% compared to hydraulic method, albeit with a minor decrease of 2.41–32.21% compared to solvent method. Nevertheless, the screw press achieves notable savings in extraction energy (35.65%) and time (92.91%). The results from mixed seeds demonstrate good consistency with diesel properties and could contribute to advanced fuel technology.