DC‐Trennung von Ricinusölfettsäure‐Estoliden

The effects of variations in pressure (20-40 kg/em2), oil-to-water ratio (1:0.4-1:1, w/w) and time (0-8 hr) on the extent of hydrolysis of castor oil were studied. Higher pressure , lower oil-to-water ratio and longer duration gave higher percentage splits. At 40 kg/em ~ pressure and an oil-to-water ratio of 1:1, ca. 92% split was obtained in 8 hr. When the oil was hydrolyzed in 2 stages at 20 kg/cm ~ with an oil-to-water ratio of 1:0.4, ca. 96% split was obtained in a total period of 10 hr. Splitting at 20 kg/cm 2 gave minimal amounts of dienoic acids because of the decomposition of estolides.

Section: Methodsmentioning

confidence: 99%

High pressure splitting of castor oil

Lakshminarayana

Subbarao

Sastry

et al. 1984

“…Thin layer chromatography (TLC) on Silica Gel G (ACME Synthetic Chemicals, Bombay, India) using a mixture of gasoline (40-60 C)/diethyl ether/ethyl alcohol/acetic acid (60:40:4:1, v/v/v/v) was carried out to detect the presence of estolides in the reduced products of castor oil FA (17). The unsaturated fatty alcohols and FA methyl esters were analyzed by gas liquid chromatography (GLC) using a Hewlett-Packard 5840 A unit equipped with a flame ionization detector (FID), a glass column (1.8 m x 6 mm) packed with 10% Silar 10 C/Gas Chromosorb W HP (100-120 mesh) and a data processor.…”

Section: Methodsmentioning

confidence: 99%

Reduction of unsaturated fatty acids and fatty alcohols with diimide from hydroxylamine‐ethyl acetate

Gangadhar

Subbarao

Lakshminarayana

1984

Hydroxylamine has been recently found to react with ethyl acetate to generate diimide in situ. This reaction was used to reduce lOundecenoic, oleic, linoleic, stearolic, concentrates of ricinoleic, cyclopentene and cyclopropene fatty acids (FA), dehydrated castor oil FA, lO-undecen-l-ol, oleyl alcohol and castor fatty alcohols. Unsaturated FA and their corresponding alcohols reacted in a similar manner. Terminally unsaturated, cyclopropene and cyclopentene FA were more reactive than oteic acid, which, in turn, was more reactive than bydroxymonoenoic acids. Conjugated dienoic FA reduced faster than nonconjugated dienoic acids. Partial hydrogenation using this reagent is particularly advantageous in determining geometry and the position of double bonds in the polyunsaturated FA, as it can be carried out in the absence of oxygen or oxidizing agents unlike bydrazine reductions.

“…Estolides are unique oligomeric fatty acids that contain a secondary ester linkage on the backbone of one of the fatty acid chains (Scheme 1). Estolides are known to exist in nature (1) and can also be prepared from homopolymerization of hydroxy fatty acids (2)(3)(4)(5) or unsaturated fatty acids (6)(7)(8). Estolides have high viscosity indices, good oxidative stability, and are biodegradable (9).…”

mentioning

confidence: 99%

Estolide production with modified clay catalysts and process conditions

Erhan

Isbell

1997

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 Fe 3+ 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. JAOCS 74, 249-254 (1997).