Sodium salts of fatty acids Soaps

Surface tension isotherms for some sodium salts of fatty acids (Cn02Na) are shown in Fig. 3.41 sodium decanoate (n=10), laurate (n=12) and myristate (n=14). Here the experimental data of [33, 65] are presented, where NaOH [65] or NaOH + NaHCOj [33] were added to the solutions of C 02Na to prevent the solutions from hydrolysis. In both cases the concentration of added sodium ions was 0.1 M. This counterion concentration was introduced in the calculations of the average ionic product as c = f (c x+xy rx  

The dependence b(nQ) for soaps is characterised not only by a much lower slope as compared to fatty acids, but also the values of b are by 3 to 4 orders of magnitude lower, as shown in Fig. 3.42. The increment of standard free energy of adsorption, calculated from the values ofb 

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The ester bonds in fats and oils can be hydrolyzed in the presence of base to produce soaps which are the sodium salts of fatty acids. Soap making is an ancient process which has changed little over millenia. 

R—C—0 Na+ glycerol sodium salts of fatty acids soap... 

Saponification Ester + sodium hydroxide > sodium salt of carboxylic acid + alcohol Triacylglycerol (fat) -1- 3 sodium hydroxide > 3 sodium salts of fatty acid (soaps) + glycerol... 

Soap Bars. In soap bars the primary surfactant is predominantly sodium salts of fatty acids. These products typically contain between 70 and 85% soap. Occasionally, potassium soap ( 5-30%) is included in the formulation to increase the solubiUty of the soap and, hence, the bar s lathering properties. The low Krafft temperatures for potassium soap are the basis for the lather enhancement, but also limits their content in bars. 

Black Liquor Soap Acidulation. Only two-thirds of a typical black Hquor soap consists of the sodium salts of fatty acids and resin acids (rosin). These acids are layered in a Hquid crystal fashion. In between these layers is black Hquor at the concentration of the soap skimmer, with various impurities, such as sodium carbonate, sodium sulfide, sodium sulfate, sodium hydroxide, sodium Hgnate, and calcium salts. This makes up the remaining one-third of the soap. Cmde tall oil is generated by acidifying the black Hquor soap with 30% sulfuric acid to a pH of 3. This is usually done in a vessel at 95°C with 20—30 minutes of vigorous agitation. Caution should be taken to scmb the hydrogen sulfide from the exhaust gas. 

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. 

A soap is the sodium or potassium salt of a long-chain fatty acid. The fatty acid usually contains 12 to 18 carbon atoms. Solid soaps usually consist of sodium salts of fatty acids, whereas liquid soaps consist of the potassium salts of fatty acids. 

Hydrophilic head Soap (sodium salt of fatty acids)... 

Saponification is used to make soaps, which usually are the sodium salts of fatty acids. A soap has both a polar end and a nonpolar end. Soaps can be used to clean nonpolar dirt and oil with water because the nonpolar dirt and oil bond to the nonpolar end of the soap molecules, and the polar end of the soap molecules is soluble in water. Thus, the dirt-laden soap molecules can be rinsed away with the water. You can make soap by doing the miniLAB on this page. 

Tall oil, derived from the Swedish tallolja meaning pine oil, is recovered from the black liquor of softwood pulping. It is taken out at an intermediate stage of the multiple-effect evaporation when the liquor contains about 30% total solids, after it is allowed to stand [21]. The soaps (sodium salts of fatty acids present) are insoluble, cream to the top of the vessel, and are skimmed off. The residual black liquor is returned to the evaporators to continue chemical recovery. The soap yield, which can range from 10 to 200 kg/tonne of pulp (or even higher for pine), is then acidified and the free fatty acids and resin acids obtained are separated by distillation. The fatty acids recovered consist mainly of oleic and linoleic acids and are employed in soap manufacture and as the drying oil components of paints and varnishes [22] (Chap. 19). Resin acids consist of terpene acids such as abietic acid and its positional and reductive variants, and are mainly employed in paper sizing. 

The most important characteristic of hard water is its reaction with soap. If distilled or soft water be shaken with a solution of soap a lather or foam is formed immediately. If, however, a dilute solution of soap be added drop by drop to some hard water in a bottle which is stoppered and shaken after each addition, it will be found that no lather is formed at first. The water, at the same time, assumes a turbidity owing to the formation of an insoluble precipitate. Finally, after sufficient soap has been added, a lather will appear. Soaps are sodium salts of fatty acids of high molecular weight, such as sodium oleate CuHggCOONa. The salts of sodium are soluble in water, but those of calcium and magnesium are not and, in hard water, the ions of these elements displace the sodium, giving precipitates of their insoluble fatty acid salts ... 

Soap is made by reacting a triglyceride with a strong base such as sodium hydroxide. The products of this reaction are glycerol and soap, which is the sodium salt of fatty acids. Write the general structure of the sodium salt of a fatty acid. 

We presented some data on pH of CO2 solutions when we discussed glycerol drying of CO2 (U.S. 4,478,612), and we also discussed the (partial) conversion of acetate salts to acetic acid using CO2 as an extractant of acetate soludons. This patent makes use of the ability of wet CO2 to convert soaps (sodium salts of fatty acids) to fatty acids which are soluble in CO2. 

Spherical vesicles (see Sec. 2.5.4) are made by the same kind of amphiphiles that form micelles. Highly soluble amphiphiles (e.g., sodium salts of fatty acids or soaps) form micelles badly soluble amphiphiles (e.g., free fatty acids) give vesicles or crystallize. Amphiphilic monomers with two or three long alkyl chains are often totally water insoluble as monomers but dissolve well as vesicular assemblies. Vesicles usually collapse upon drying (Fig. 1.5.8a), but one isolable monolayer vesicle made of rigid carotenoid bolaamphiphiles has also been reported (Fig. 5.5). Hydrogen bond chains convert spherical vesicles to tubules. Such tubules can again be isolated in the dry form and can be stored. They are particularly stable if monolayer membranes are used (Fig. 1.5.8b). 

In the manufacture of soap, a hot concentrated solution of sodium hydroxide is added to vegetable oils or animal fats. Vegetable oils and fats contain many different esters, such as glyceryl stearate (formed from an alcohol such as glycerol and a long-chain fatty acid such as stearic acid). Sodium salts of fatty acids (palmitic, stearic, and oleic) form soap, which separates and floats on the surface when... 

For example, soap is made by heating a fat with sodium hydroxide solution. The product is a mixture of sodium salts of fatty acids, obtained from the fat. Fatty acids are chemically similar to acetic acid, but they consist of long chains of carbon atoms. Compare the structure of the acetate ion with that of the stearate ion. (Stearic acid is a typical fatty acid.) ... 

Soap is typically made of sodium salt of fatty acid(s). A main ingredient of animal fat is glycerol esters of fatty acids. A fatty acid is made of a long carbon chain plus an acid unit (COOH, as you saw in the case of acetic acid above) at the end for example. 

SNG Substitute natural gas. soaps Sodium and potassium salts of fatty acids, particularly stearic, palmitic and oleic acids. Animal and vegetable oils and fats, from which soaps are prepared, consist essentially of the glyceryl esters of these acids. In soap manufacture the oil or fat is heated with dilute NaOH (less frequently KOH) solution in large vats. When hydrolysis is complete the soap is salted out , or precipitated from solution by addition of NaCl. The soap is then treated, as required, with perfumes, etc. and made into tablets. 

Soaps are composed of sodium salts of various fatty acids. These acids include those with the general structure CH3-(CH2) -COOH where n = 6 (caprylic acid), 8 (capric acid), 10 (lauric acid), 12 (myristic acid), 14 (palmitic acid), and 16 (stearic acid). Oleic acid (CH3-(CH2)7-CH=CH-(CH2)7-COOH) and linoleic acid (CH3-(CH2)4-CH=CH- H2-CH=CH-(CH2)7-COOH) are also common soap ingredients. These sodium salts readily dissolve in water, but other metal ions such as Ca2+ and Mg2+ form precipitates with the fatty acid anions. For example, the dissolution of the sodium salt of lauric acid and the subsequent formation of a precipitate of the lauric acid anion with calcium ion is given by... 

Soap an emulsifying agent made from sodium or potassium salts of fatty acids. 

Soaps are salts of fatty acids (weak acids) and strong bases such as sodium hydroxide or potassium hydroxide. Soaps therefore dissolve in water to form alkaline solutions. 

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