Saponification of Fats and Oils Soap

When a fat or oil is heated with alkali (e.g., NaOH), the ester is converted to glycerol and the salts of fatty acids. The reaction is illustrated here with the saponification of glyceryl tripalmitate. 

CH20C(CH2)i4CH3 glyceryl tripalmitate (tripalmitin) (from palm oU) 

The salts (usually sodium) of long-chain fatty acids are soaps. 

In the continuous process, which is more common today, the fat or oil is hydrolyzed by water at high temperatures and pressures in the presence of a catalyst, usually a zinc soap. The fat or oil and the water are introduced continuously into opposite ends of a larger reactor, and the fatty acids and glycerol are removed as formed, by distillation. The acids are then carefully neutralized with an appropriate amount of alkali to make soap. 

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Saponification of Fats and Oils Soaps and Detergents 1207 An alkylbenzenesiilfonate detergent... 

Hydrogenation of Vegetable Oils Saponification of Fats and Oils Soap... 

Commercially, soap is most commonly produced through either the direct saponification of fats and oils with caustic or the hydrolysis of fats and oils to fatty acids followed by stoichiometric (equal molar) neutralization with caustic. Both of these approaches yield workable soap in the form of concentrated soap solutions (- 70% soap). This concentration of soap is the target on account of the aqueous-phase properties of soap as well as practical limitations resulting from these properties. Hence, before discussing the commercial manufacturing of soap, it is imperative to understand the phase properties of soap. 

Direct Saponification. Direct saponification of fats and oils is the traditional process utilized for the manufacturing of soap. Commercially this is done through either a kettle boiling batch process or a continuous process. 

Comparison of Base Soap Manufacturing Routes. Direct saponification of fats and oils is well known, characteri2ed, and straightforward requires Httle equipment and is relatively energy-efficient. However, it is not very effective with regard to changes in the fats and oils ratio desired for finished soap bar formulations. Furthermore, direct saponification has the drawbacks of lower glycerol yields, limited flexibiUty toward... 

Recovery from the spent lye liquor obrd on saponification of fats and oils in the soap industry... 

Saponification of fats and oils by boiling with strong base yields glycerol and the sodium salts of fatty acids. The latter are soaps. Soaps contain a long carbon chain that is lipophilic and a terminal polar group that is hydrophilic. Soap molecules aggregate in water to form micelles, which help emulsify droplets of oil or grease. 

Saponification of fats and oils using caustic soda to form soap and glycerine. 

Esters. Organic esters of all kinds, including the esters of carbohydrates, are quite subject to hydrolysis with acids, bases, and, in many cases, enzymes. In this connection, the term saponification is commonly used instead of hydrolysis. The most important example is that of the saponification of fats and oils to make glycerol and either soap or fatty acids. The decomposition of ethyl and methyl acetates by water plus a catalyst has probably received more attention than any other case of hydrolysis by reason of its bearing on the general subject of catalysis. Hydrolysis of esters is reversible, unlike that of the carbohydrates, so that the equilibrium point may be approached from both sides. The following equations represent typical cases of ester hydrolysis ... 

We will see in Chapter 8 that saponification of fats and oils is important in the production of soaps. 

M Figure 25.18 Saponification of fats and oils has long been used to make soap. This etching shows a step in the soap-making process during the midnineteenth century. 

The soap detergents industry uses NaOH for sodium phosphate production, soap manufacture by saponification of fats and oils, and the production of detergents from organic sulfonic acid and NaOH. 

Fatty Acid Neutralization. Another approach to produce soap is through the neutralization of fatty acids with caustic. This approach requires a stepwise process where fatty acids are produced through the hydrolysis of fats and oils by water, followed by subsequent neutralization with appropriate caustics. This approach has a number of inherent benefits over the saponification process. 

In general, two types of chemical reactions are utilized in the manufacture of soap the saponification of triglycerides (fats and oils) and the neutralization of fatty acids (which themselves are produced from the triglycerides by a variety of methods, most notably splitting or hydrolysis of fats and oils with steam under high pressure). Sodium hydroxide (the predominant alkali employed in the manufacture of soaps), potassium hydroxide, sodium carbonate, and triethanolamine are... 

Fats and oils can be saponified via the full-boiled process. The saponification process can be briefly described as follows. A refined blend of fats and oils is charged into a kettle and a predetermined amount of soap lye with sufficient concentrations of caustic soda, and salt is added. The mixture is boiled vigorously, using closed steam coils, until saponihcation is almost complete. The amount of caustic soda added is deliberately made less than the stoichiometric requirement, to ensure that the spent soap lye containing the glycerine has minimum alkalinity. The caustic soda in the spent soap lye is neutralized during subsequent treatment of the latter. 

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... 

Toilet soaps are obtained from either saponification of fat and natural oil mixture or neutralization of the similarly derived fatty acids. 

G. Verseifung F. saponification S. is one of the oldest reactions practiced by human beings. It is the - splitting of - fats and oils into - soap and - glycerol. 

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. 

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