Extraction of oil from Moringa oleifera kernels using supercritical carbon dioxide with ethanol for pretreatment: Optimization of the extraction process

The study involved the extraction of oil from Moringa oleifera (MO) kernels using supercritical fluid extraction (SFE) technique. The arrays of operating parameters are extraction condition, loading configuration, and SC-CO2 with ethanol addition for substrate pretreatment. It identifies a combination of operating parameters that provide a higher yield. The experiments were conducted in the pressure range of 15–30 MPa, 35–60 °C temperature interval, average particle size of 0.16–1.12 mm and CO2 flow rate of 0.5 m3/h. Adding 10% EtOH for substrate pretreatment, increased 10% in the yield. No significant difference in yield and fatty acid content between the oil from SC-CO2-EtOH and Soxhlet extraction with n-hexane was detected. Loading the seeds in multiple-staged trays increased to as much as 26.89% in the yield against randomly packed configuration. Response surface methodology, predicted an optimal oil yield of 37.84% at a pressure of 28.97 MPa, 44.30 °C temperature, and particle size of 0.54 mm. A crossover pressure point of Ben oil was found within the range 22.5–30 MPa.