Alternative hydrocarbon solvents for cottonseed extraction

• Published in: Journal of the American Oil Chemists' Society Vol. 72; no. 6; pp. 653 - 659
• Main Authors: Wan, P.J. (USDA, ARS, SRRC, New Orleans, LA.), Pakarinen, D.R, Hron, R.J. Sr, Richard, O.L, Conkerton, E.J
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer‐Verlag 01.06.1995; Springer
• Subjects: ACEITE DE ALGODON; ALIMENTOS; Alternative solvents; Biological and medical sciences; CALIDAD; COTTONSEED; COTTONSEED OIL; cyclohexane; cyclopentane; extraction; extraction efficiency and rate; Fat industries; Food industries; FOOD QUALITY; FOODS; Fundamental and applied biological sciences. Psychology; GRAINE DE COTON; heptane; hexane; HIDROCARBUROS; HUILE DE COTON; hydrocarbon solvents; HYDROCARBONS; HYDROCARBURE; isohexane; miscella; miscella concentration; neohexane; PRODUIT ALIMENTAIRE; PROPERTIES; QUALITE; QUALITY; SEMILLA DE ALGODON; SOLVANT; SOLVENTES; SOLVENTS; Performance evaluation; Hydrocarbon; Edible oil; Solvent extraction; Cottonseed oil; Extraction process
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/BF02635650

Hexane has been used for decades to extract edible oil from cottonseed. However, due to increased regulations affecting hexane because of the 1990 Clean Air Act and potential health risks, the oil‐extraction industry urgently needs alternative hydrocarbon solvents to replace hexane. Five solvents,n‐heptane, isohexane, neohexane, cyclohexane, and cylopentane, were compared with commercial hexane using a benchscale extractor. The extractions were done with a solvent to cottonseed flake ratio of 5.5 to 1 (w/w) and a miscella recycle flow rate of 36 mL/min/sq cm (9 gal/min/sq ft) at a temperature of 10 to 45°C below the boiling point of the solvent. After a 10‐min single‐stage extraction, commercial hexane removed 100% of the oil from the flakes at 55°C; heptane extracted 100% at 75°C and 95.9% at 55°C; isohexane extracted 93.1% at 45°C; while cyclopentane, cyclohexane, and neohexane removed 93.3, 89.4, and 89.6% at 35, 55, and 35°C, respectively. Each solvent removed gossypol from cottonseed flakes at a different rate, with cyclopentane being most and neohexane least effective. Based on the bench‐scale extraction results and the availability of these candidate solvents, heptane and isohexane are the alternative hydrocarbon solvents most likely to replace hexane.