Estolide production with modified clay catalysts and process conditions

• Published in: Journal of the American Oil Chemists' Society 1997-03, Vol.74 (3), p.249-254
• Main Authors: Erhan, S.M. (New Crops Research, ARS, USDA, Peoria, IL.), Isbell, T.A
• Format: Article
• Language: English
• Subjects: ACEITES VEGETALES; ACIDE GRAS; ACIDE OLEIQUE; Acidification; ACIDO OLEICO; ACIDOS GRASOS; Catalysis; Catalysts; Catalytic reactions; Cation exchanged clays; Chemistry; Clay; estolide; Exact sciences and technology; FATTY ACIDS; General and physical chemistry; HUILE VEGETALE; Iron; LIMNANTHES; meadowfoam oil fatty acids; Montmorillonite; montmorillonite clays; nitrogen sparging; Oils & fats; OLEIC ACID; oleic homopolymer; PLANT OILS; Reagents; Salts; SEED OILS; Sparging; surface‐active agents; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-997-0131-z

The 20% yields of estolides prepared from oleic acid and meadowfoam oil fatty acids are improved when the montmorillonite clay catalysts are modified to increase their activity. Changes we explored included acidifying the clay, treating to increase the surface area of clay to introduce new active sites, and decreasing the ionic character of the clay surface to enhance adsorption of the fatty acids. We also evaluated the use of higher levels of clay in the reactions. Clays treated with Fe3+ salts increase the estolide yield from 21 to 27%, a 28% increase. Clay catalysts were also treated with surface‐active reagents. The most active were cationic surfactants, and montmorillonite clays treated with cetyltrimethylammonium chloride increased the estolide yield to 30%. Estolide yields could not be improved beyond 30% by increasing the amount of clay. However, nitrogen sparging increases the efficiency of stirring and increased the estolide yield to 35% estolide.