Hydrogenation oleic acid

Reflectivity data were collected for six different isotopic forms of the equimolar DPPC/oleic acid mixed monolayer using either hydrogenated oleic acid (h-OA) or perdeuterated oleic acid (d-OA) in conjunction with h-DPPC or d-DPPC. Additional isotopic variation was provided by using either ACMW or D2O as the subphase. Again, each monolayer was studied at three surface coverages of approximately 50, 60 and 70 A molecule. 

Stearic acid and oleic acid are fatty acids, compounds that contain a carboxy group (COOH) attached to the end of a long carbon chain. Stearic acid is a saturated fatty acid because each carbon atom in its long chain has the maximum number of bonds to hydrogen. Oleic acid is an unsaturated fatty acid because its carbon chain contains one (cis) double bond. The presence of a double bond greatly affects the chemical and physical properties of these fatty acids. In Chapter 10 we learn about alkenes, organic compounds that contain carbon-carbon double bonds. 

Although Sabatier and Senderens had hydrogenated oleic acid vapor to produce stearic acid, they did not extend this work themselves. The appendix to Chapters 11 and 12 in their book describes early work to about 1916, by others who used nickel and palladium catalysts. They described the use of nickel supported on pumice, kieselguhr, asbestos, and wood charcoal. ... 

Fokin, who was also interested in precious metal catalysts, had earlier used platinum or palladium blacks to hydrogenate oleic acid at ambient temperature and much lower pressures than those used by Ipatieff. Platinum or palladium black catalysts, which were finely divided metals containing some oxygen, were then... 

What volume of H2(g) at 25 °C and 752 mmHg is required to hydrogenate oleic acid, Ci7H33COOH(l), to produce one mole of stearic acid, Ci7H35COOH(s)7 Assume reaction (22.52) proceeds with a 95% yield. 

Dissolve 7 g. of pure oleic acid in 30 ml. of dry ethyl chloride (chloroform may be used but is less satisfactory), and ozonise at about —30°. Remove the solvent under reduced pressure, dissolve the residue in 50 ml. of dry methyl alcohol and hydrogenate as for adipic dialdehyde in the presence of 0 5 g. of palladium - calcium carbonate. Warm the resulting solution for 30 minutes with a slight excess of semicarbazide acetate and pour into water. Collect the precipitated semicarbazones and dry the... 

Multiply unsaturated linolenic and linoleic acid residues make triglycerides more vulnerable to oxidative degradation than oleic acid which is relatively stable. It is therefore desirable to hydrogenate the most unsaturated residues selectively without production of large quantities of stearic (fully saturated) acid. The stepwise reduction of an unsaturated oil may be visualized as ... 

Positionalisomeri tion occurs most often duting partial hydrogenation of unsaturated fatty acids it also occurs ia strongly basic or acidic solution and by catalysis with metal hydrides or organometaUic carbonyl complexes. Concentrated sulfuric or 70% perchloric acid treatment of oleic acid at 85°C produces y-stearolactone from a series of double-bond isomerizations, hydration, and dehydration steps (57). 

When tallow fatty acids are the feed, stearic acid (actually 60/40 C16/C18) and oleic acids are the products. Solvent separation is also used to separate stearic acid from isostearic acid when hydrogenated monomer is the feed, and oleic acid from linoleic acid when using tall oil fatty acids as feed. 

A U.S. patent describes the reaction of commercial oleic acid with hydrogen peroxide in acetic acid foUowed by air oxidation using a heavy metal compound and an inorganic bromine or chlorine compound to catalyze the oxidation. ExceUent yields of dibasic acids are obtained (up to 99%) containing up to 72% azelaic acid (55). 

Structure and Mechanism of Formation. Thermal dimerization of unsaturated fatty acids has been explaiaed both by a Diels-Alder mechanism and by a free-radical route involving hydrogen transfer. The Diels-Alder reaction appears to apply to starting materials high ia linoleic acid content satisfactorily, but oleic acid oligomerization seems better rationalized by a free-radical reaction (8—10). 

Examples are given of common operations such as absorption of ammonia to make fertihzers and of carbon dioxide to make soda ash. Also of recoveiy of phosphine from offgases of phosphorous plants recoveiy of HE oxidation, halogenation, and hydrogenation of various organics hydration of olefins to alcohols oxo reaction for higher aldehydes and alcohols ozonolysis of oleic acid absorption of carbon monoxide to make sodium formate alkylation of acetic acid with isobutylene to make teti-h ty acetate, absorption of olefins to make various products HCl and HBr plus higher alcohols to make alkyl hahdes and so on. 

Powdered aluminium had been added to oleic acid. The mixture detonated after being prepared. Such an accident could not be repeated and it was thought that it was caused by the presence of a peroxide formed by the effect of air on oleic acid. In fact, the acid functional group has obviously nothing to do with the peroxidation. It is more likely that the chain s double bond that activates p hydrogen atoms (ally position) was involved in it. This is a well-known phenomenon since it is responsible for the rancidity of some oils and greases. 

The major fatty acids present in plant-derived fatty substances are oleic acid (9-octadecenoic, C18 l), linoleic acid (9,12-octadecadienoic, C18 2) and the conjugated isomers thereof and linolenic acid (9,12,15-octadecatrienoic, C18 3) (Scheme 31.1). Their rates of oxygen absorption are 100 40 1, respectively, hence partial hydrogenation with consequent lowering of the iodine number would lead to a significant increase in oxidative stabihty, particularly when C18 3 is reduced. 

Oleic acid was hydrogenated at 25-17 C with mild agitation in the presence of a slurried catalyst with 5.3 wt7. platinum. These data were obtained,... 

Odor and color stability problems were also related to the alkyl chains used for SAI. These could be traced to the oxidation of unsaturated carbons, such as oleic acid (Ci8 fatty acid with a single double bond between carbon 9 and 10, i.e. bond position 9 counted from the carboxyl carbon), linoleic acid (Cis fatty acid with two double bonds at position 9 and 12), and linolenic acid (Cis fatty acid with three double bonds at position 9, 12, and 15). Natural coconut fatty acid contains about 6% oleic acid, about 3% linoleic acid, and less than 1% linolenic acid. Tallow fatty acid contains nearly 44% oleic and about 6% of other unsaturates [20]. Partial hydrogenation of the coconut fatty acid used in the manufacture of SCI served to eliminate linoleic and linolenic acids for improved odor stability, while not eliminating oleic acid, which is important for good lather. 

In either case, for the conversion of the linoleic and oleic acids into stearic acid, the temperature of the acids should be between 200° and 220° C. When the nickel is introduced, in the form of carbonyl, at the same time as the hydrogen, the carbonyl is decomposed into metallic nickel and carbon monoxide—the latter taking no part whatever in the reaction and being available for the production of further nickel carbonyl... 

Mixed micelles (e.g., monoolein taurocholate, oleic acid taurocholate, oleic acid-polyoxyethylene hydrogenated castor oil (HCO 60), and oleic acid glycocholate)... 

Ileal oleic acid uptake. Hydrogenated oil, administered to rats at a dose of 5 g/100 g of diet, produced saturable kinetics in ileal brush border membrane vesicles = 0.23... 

Jejunal oleic acid uptake. Hydrogenated oil, administered to rats at a dose of 5 g/100 g of diet, produced saturable kinetics in jejunal brush border membrane vesicles = 0.15 + 01 pmol/mgprotein/5 minutes, and K = 136 + 29.1 nmol for controls, and Vmax =03 + 01 pmol/mg protein/5 minutes and K = 124.5 + 72.6 nmol for the coconut oil-fed group . 

Herbicide-resistant and pesticide-resistant crops should avoid soil erosion and limit the spread of synthetic herbicides and pesticides. Modified crops may also provide heat-stable monounsaturated oleic acid, avoiding the problem of heat-unstable poljainsaturated fetty acids that give unhealthy trans-fatty acids as side products of industrial hydrogenation (Mazur 1999). On the longer term, biotechnology may also provide renewable fuel and raw chemicals that may replace petroleum. 

To a well-stirred mixture of 141 g. (0.5 mole) of oleic acid (Note 1) and 425 ml. of formic acid (Note 2) in a 1-1. three-necked llask at 25° is added the appropriate amount (Note 3) of 30% (100 volume) hydrogen peroxide (approximately 60 g.) over a 15 minute period (Note 4). The reaction becomes mildly exothermic after a lag of about 5-10 minutes, and homogeneous after about 20 30 minutes. The temperature is maintained at 10" with a cold water bath at the beginning, and with a warm water bath or heating mantle toward the end, of the reaction. 

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