Fatty acids neutralization

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. 

Azeotropic and extractive distillation Distillation processes Extractive distillation(s) argon, 13 460 for aroma isolation, 11 519 atmospheric, 13 646 batch versus continuous, 3 780 of coal-tar naphthalene, 17 78-79 corrosion, 3 779-780 of crude oil, 12 401-402 13 593 debottlenecking, 13 521 in fatty acid neutralization, 22 740 favorable vapor-liquid equilibria, 3 778 feed composition, 3 778 general separation heuristics for, 22 316-317... 

Zn-EMAA ionomers, 74 464-465, 474, 482. See also EMAA ionomers Zn-EPDM elastomeric ionomers, 74 482 ZnSe system, for laser diodes, 22 179 Zn-soap, in fatty acid neutralization, 22 740... 

Figure 4 Soap from fatty acid neutralization (C) (from Ref. 13).

Parameter Batch kettle (A) Fat splitting (B) Fatty acid neutralization Glycerine (C) concentration (D) Glycerine Flakes and distillation (E) powders (F) Bar soap (G) Liquid soap (H)... 

Zhang J. P. and Sun G. Y. (1995). Free fatty acids, neutral glycerides, and phosphoglycerides in transient focal cerebral ischemia. J. Neurochem. 64 1688-1695. 

Fig. 36.2). The methyl ester process for soap manufacture is typically more capital and cost intensive versus the more traditional fats/oils saponification and fatty acid neutralization processes. 

The following describes neutral fat saponification and fatty acid neutralization, the two principal processes used for manufacture of soap in the world markets today. 

Fatty Acid Neutralization. The acid-base reaction of fatty acids with alkali to produce soap (below) is much faster than the corresponding reaction of triglycerides with alkalis. 

A typical Mazzoni fatty acid neutralization soap plant is illustrated in Fig. 36.5.6 The operation of this plant involves the pumping of the reactants through preheaters to a turbodisperser, or high-shear mixer, where the contact of the reactants with each other initiates the formation of neat soap. The soap mass, which is partially reacted at this stage, then proceeds to the mixer where it is recirculated until the neutralization is complete. The completion of the neutralization reaction is monitored continuously by an electric potential (millivolt, mV) measurement for alkalinity. The neat soap is then dried by vacuum spray-dryers, as described earlier, to produce soap pellets ready for finishing into soap bars. 

Fig. 36.5. Continuous fatty acid neutralization plant. (Courtesy G. Mazzoni S.p.A., Busto Arsizio, Italy.)...

The principal lipid constituent of the tubercle bacilli was a wax-like substance. Anderson obtained this by chloroform extraction of fat-free bacilli. The preliminary removal of lipids with alcohol and other solvents served to dissolve the free fatty acids, neutral fat and phospha-tides. The crude wax was fractionated with alcohol or acetone. The purified derivative was a white amorphous powder containing 0.41% nitrogen and 0.77% phosphorus. The substance was very resistant to acid hydrolysis. Continuous treatment with acidified alcohol resulted in very slow hydrolysis. Alkaline hydrolysis proceeded very rapidly, with the formation of ether-soluble components together with a water-soluble polysaccharide. 

By-products. Chemical Refining. The neutralization of free fatty acid in the crude pahn oil with caustic soda results in the formation of soapstock, which is treated with dilute sulfuric acid of pH 2.0-3.5 at 110-130°C for 30 min. A by-product called palm acid oil is then separated from the aqueous phase by centrifugation followed by hot-water washing. It consists mainly of free fatty acids, neutral oil, and partial glycerides. A small amount of unsaponifiable matter is also present. Characteristics and properties of palm acid oil (derived from chemical refining of crude pahn oil, stearin, and olein) are given in Table 35 (55). 

Numerous catalysts have been used in the production of CLA. We have found that hydroxides of lithium, sodium, and potassium are all capable of generating CLA in various solvents. As fatty acids neutralize the catalyst, it is necessary to add at least one mole of catalyst for every mole of fatty acid in the reaction to ensure soap is generated. We have found that, on a molar basis, potassium hydroxide has proven to be a more effective catalyst than sodium hydroxide, with lithium hydroxide the least effective and not suited for industrial CLA production. On a weight basis, sodium and potassium hydroxide have similar efficiency of conversion. Although sodium hydroxide is much less expensive than potassium hydroxide, the disposal costs for the waste neutralized alkali should also be considered. Potassium salts are easily used as fertilizer and can be applied to fields, whereas sodium salts cannot be disposed of in a similar fashion. 

MAZZONI offer two fatty acid neutralization processes. The SC process uses sodium hydroxide to neutralize fatty acids, prior to drying, in a loop reactor fitted with an in-line dynamic homogenizer. Additional sodium chloride is metered as a separate stream. 

When soap is produced from most triglyceride saponification or fatty acid neutralization soap-... 

Yeast and bacteria can produce biosurfactants, biological surfactants from various substrates including sugars, oils, alkanes and wastes [5]. Some types of biosurfactants are glycolipids, lipopeptides, phospholipids, fatty acids, neutral lipids, polymeric and particulate compounds [6]. Most are either anionic or neutral, while only a few with amine groups are cationic. The hydrophobic part of the molecule is based on long-chain fatty acids, hydroxy fatty acids or a-alkyl-jS-hydroxy fatty acids. The hydrophilic portion can be a carbohydrate, amino acid, cyclic peptide, phosphate, carboxylic acid or alcohol. 

Most raw materials and many formulated products can be analysed without isolation of the surfactants. For some purposes, however, e.g. determination of molecular weight by titration, the surfactant must be isolated in a pure form. Liquid-solid extraction is useful for this purpose. It is also sometimes desirable to extract fatty acids, neutral fatty matter and/or weak fatty bases, either to determine them or to prevent interference with some other determination. Liquid-liquid extraction is appropriate for this. A special case is the analysis of structured bleaches, which may contain surfactants in strong hypochlorite. The bleach makes most analytical processes for the surfactants difficult or impossible, and the procedure given below is a useful first step. 

Current mass market soap manufacturing is based primarily around continuous soap making using either fat saponification or by fatty acid neutralization, utilizing a wide variety of natural and synthetic feedstocks. The soap chips produced are then usually finished using a high-speed soap line comprised of refiner mill, extruder, and stamper. Batch... 

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