Saponification saturated fatty acid

Properties A drying oil similar in properties and uses to linseed. Edible, iodine value approximately 160, d 0.923, refr index 1.470-1.472. Contains approximately 10% saturated fatty acids (palmitic and stearic), unsaturated acids present are linoleic, lin-olenic, and oleic. Saponification value 190-193. 

Glycerides are major components of edible oils. Those which contain fatty acids with a relatively high degree of unsaturation are thought to provide benefits in the diet. The ability of highly unsaturated oils to polymerize in the presence of air has made them useful for paints. Glycerides that contain a predominance of saturated fatty acids can be converted to salts by treatment with bases (saponification). Sodium and potassium salts are useful for soaps, whereas lithium salts are components of lubricants. Triglycerides from seed oils possibly represent the most likely substitute for petroleum in the future. 

Nystrom and co-workers (1959) applied the Wilzbach technique to H labeling of methyl esters of saturated fatty acids, and the anticipated substitution of hydrogen by tritium occurred. In this procedure, gram amounts of methyl esters of palmitic and stearic acids were exposed to 1 Ci of H2 at room temperature. The fatty acid esters were deposited as thin layers by solvent evaporation on the inside wall of 1- X 10-inch reaction tubes. Methyl laurate and methyl myristate, being liquid at room temperature, required sealed ampules equipped with break seals the ampules were rotated to provide a continuously renewed thin film during their exposure to 5 Ci of tritium gas. Purification of the tritiated methyl esters includes saponification and extraction of the free acid with diethyl ether. 

Carboxylate soaps are most commonly formed through either direct or indirect reaction of aqueous caustic soda, ie, alkaH earth metal hydroxides such as NaOH, with fats and oils from natural sources, ie, triglycerides. Fats and oils are typically composed of both saturated and unsaturated fatty acid molecules containing between 8 and 20 carbons randomly linked through ester bonds to a glycerol [56-81-5] backbone. Overall, the reaction of caustic with triglyceride yields glycerol (qv) and soap in a reaction known as saponification. The reaction is shown in equation 1. 

The raw materials for the manufacture of soap, the alkali salts of saturated and unsaturated C10-C20 carboxylic acids, are natural fats and fatty oils, especially tallow oil and other animal fats (lard), coconut oil, palm kernel oil, peanut oil, and even olive oil. In addition, the tall oil fatty acids, which are obtained in the kraft pulping process, are used for soap production. A typical formulation of fats for the manufacture of soap contains 80-90% tallow oil and 10-20% coconut oil [2]. For the manufacture of soft soaps, the potassium salts of fatty acids are used, as are linseed oil, soybean oil, and cottonseed oil acids. High-quality soap can only be produced by high-quality fats, independent of the soap being produced by saponification of the natural fat with caustic soda solution or by neutralization of distilled fatty acids, obtained by hydrolysis of fats, with soda or caustic soda solutions. Fatty acids produced by paraffin wax oxidation are of inferior quality due to a high content of unwanted byproducts. Therefore in industrially developed countries these fatty acids are not used for the manufacture of soap. This now seems to be true as well for the developing countries. 

Waxes are esters of fatty acids with long chain primary alcohols (Figure 12.2). The fatty acid is usually straight chain which may be saturated or mono-unsat-urated although occasionally branched chain or hydroxy acids are found. They are extremely non-polar compounds and are relatively inert chemically but they can be hydrolysed using a strong alkali, such as potassium hydroxide, a process called saponification. 

Since the preparation of soap is typical of a fairly complex reaction, chemically, and since it is common, it serves as a useful example of the saponification operation. The complication, of course, occurs because the usual esters used for soap arc file glycerol esters of fatty acids, saturated and uiisaturated. Thus the saponification of stearin (glycerol trixlearale) is commonly shown as follow s ... 

Saponification refers to alkaline hydrolysis of fats and oils to give glycerol and the alkali metal salt of a long chain fatty acid (a soap). In this experiment saponification of olive oil is accomplished in a few minutes by use of a solvent permitting operation at 160°C. Of the five acids found in olive oil, listed in Table 1, three are unsaturated and two are saturated. Oleic acid and linoleic acid are considerably lower melting and more soluble in organic solvents than the saturated components, and when a solution of the... 

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