Mechanical Screw-press Extraction of Jatropha curcas Seed Oil in Senegal: Process Description and Feasibility Assessment

Faced with the increasing effects of climate change, the development of resilient plants adapted to arid environments, such as Jatropha curcas , is a strategic priority to meet the energy needs of drylands. This plant is used for its valuable oil content and its ability to offer an alternative to fossil fuels in the context of global warming. In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. This study is devoted to a mechanical pressing of Jatropha curcas seeds, harvested in the Fatick region of central Senegal, in order to optimize its oil, using a screw press at 50°C. After hulling, washing and drying, the seeds were carefully selected and introduced into a twin-screw extruder. After 24 hours of settling, the Jatropha oil was filtered and then stored in clean, dry containers. The extraction rate obtained, estimated at 10.86%, reveals that this technique is significantly less productive than chemical extraction by Soxhlet, which achieves a yield of approximately 25%. However, its main advantage lies in the superior quality of the oil produced: it is completely free of chemical residues, making it particularly suitable for sensitive applications. Indeed, this oil can be used directly, without a refining step, as biofuel in diesel engines, and it is also a prime raw material for soap manufacturing.