Integrated membrane process for pretreating and desolventizing hexane-soybean oil miscella – A pilot plant study

• Published in: Journal of membrane science 2024-06, Vol.704, p.122808, Article 122808
• Main Authors: Subramanian, R., Muthuganesan, N., Venu, S., Gopika, S.K., Thummar, Utpal G., Chakkaravarthi, A., Singh, Puyam S., Singh, Satyendra
• Format: Article
• Language: English
• Subjects: hexane; Micelle-enhanced ultrafiltration; nanofiltration; Organic solvent nanofiltration; phospholipids; Pilot scale study; Solvent recovery; solvents; soybean oil; Spiral-wound membrane modules; streams; ultrafiltration; vegetable oil
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2024.122808

The study aimed to develop a membrane desolventizing technology for solvent recovery in vegetable oil extraction. Pretreatment of crude miscella is a prerequisite for an organic solvent nanofiltration (OSN) based desolventizing process. Solvent-resistant ultrafiltration (SRUF) membrane employed in micelle-enhanced ultrafiltration (MEUF) of hexane-crude soybean oil miscella displayed high phospholipids (PL) rejection (98.5 %) and productivity (∼28 L/m2/h), accompanied with a moderate oil rejection (∼22 %). The PL-rich retentate fraction was alkali-treated to recover the oil in the stream (8.8 %). This complementary pretreatment approach met the quality requirements and maximized the yield of treated oil (>98 %) while reducing the chemicals in the process. A subsequent two-stage desolventizing of MEUF-treated miscella with solvent-resistant nanofiltration (SRNF) membrane reduced the oil-in-permeate to 1.37 %, achieving the set recycling criteria (