Fatty methylation

Two important widely used sulfonic acids are known as TwitcheU s reagents, or as in Russia, the Petrov catalysts. These reagents are based on benzene or naphthalene ( ) and (12), [3055-92-3] and [82415-39-2] respectively. The materials are typically made by the coupling of an unsaturated fatty acid with benzene or naphthalene in the presence of concentrated sulfuric acid (128). These sulfonic acids have been used extensively in the hydrolysis of fats and oils, such as beef tallow (129), coconut oil (130,131), fatty methyl esters (132), and various other fats and oils (133—135). TwitcheU reagents have also found use as acidic esterification catalysts (136) and dispersing agents (137). 

Fig. 7). This lower adsorption of the sodium ct-sulfo fatty methyl esters on kaolin is in accord with their somewhat worse detergency. 

An alkaline catalyst, sodium methoxide, is created in the same reactor as the ester interchange by first adding sodium metal to the methanol before the triglyceride is introduced. The reaction is performed batch by batch in a carbon-steel vessel at atmospheric pressure. The reaction, shown in the top part of Figure 15—2, results in glycerol and three fatty methyl esters. 

To continue the process, the fatty methyl esters are phase-separated from the glycerin (or glycerol—same thing, just to keep you on your toes), washed with water to remove any trace amounts of methanol and glycerin and dried. In a second reaction, the methyl esters are hydrogenated to get the fatty alcohols (in the southeast corner of Figure 15—2). The catalyst is usually a mixture of cupric chromite and cupric oxide in the form of a finely divided powder. Conversion of the triglycerides is about 95%. 

In 2005, Jerome and co-workers investigated the selective monoesterification of sucrose with various fatty methyl esters, in the presence of a strongly basic guanidine (triazabicyclo[4.4.0.]dec-5-ene (TBD)) grafted either over silica (HMS-TBD) or a polystyrene support (PS-TBD) (Scheme 12) [129]. 

Fig. 36.2. Fatty methyl ester process for soap manufacture.

In recent years, soap manufacture by an alternate route, the saponification of fatty methyl esters, has been under development, most notably in Japan (Lion Corporation) and Italy (Ballestra). The fatty methyl esters are obtained from the methanolysis of triglycerides inorganic alkali, quaternary ammonium salts, and enzymes (lipase) have been used as catalysts for methanolysis in commercially practiced processes... 

Splitting, or the hydrolysis of triglycerides is usually performed with high-pressure steam, resulting in the formation of split crude fatty acids and glycerin. The production of fatty acids by more sophisticated splitting processes, such as hydrolysis of fatty methyl esters, ozono lysis of unsaturated fatty acids, and chemical oxidation is practiced in special situations. 

Methyl Ester-Based Processes. The fatty methyl esters are produced predominantly by the transesterification of fats and oils with methanol in the presence of an alkaline catalyst under very mild reaction conditions.l5a,b They are used in the production of lauric-type (Cl2) alcohols. The short-chain fatty methyl esters (C8-Cl0), produced as by-products via the fractional distillation of crude lauric-type (coconut, palm kernel) methyl esters, are converted to fatty acids via acidic or alkaline hydrolysis (Fig. 36.12). The hydrolysis of short-chain fatty methyl esters by stream splitting or Twitchell-type processes is not very efficient because of unfavorable equilibrium constants.16a,b... 

Recently, soap manufacture by the saponification of fatty methyl esters has been developed in Japan and Italy. The methanolysis of triglycerides takes place in the presence of enzymes (lipase) as catalysts to produce fatty methyl ester and glycerin. The fatty methyl ester undergoes the saponification and forms the final product [1-6]. 

Distilled fatty methyl esters with low iodine values are used as the starting raw material for the production of SME. The fatty methyl ester is first reacted with sulfur trioxide at 80-90°C in a falling-film reactor. The dark product obtained from this process is bleached using hydrogen peroxide. After bleaching, the lighter color product is neutralized with alkali to produce an a-sulphonated methyl ester. 

High temperature and pressure hydrogenation of fatty methyl esters... 

To date the most common method for the production of fatty alcohols is via high-temperature and high-pressure hydrogenation of fatty methyl esters using a... 

On the basis of the above reported results, Barrault et al. (24] studied the selective synthesis of monoglycerides 51 starling from glycerol 49 and fatty methyl esters 50 promoted by both PTBD with 2.5 mmol/g loading and homogeneous M fBI) (Scheme 13). 

These surfactants are produced by preparing A -methyl-glucamine, followed by reaction of the latter with an alkyl (or fatty) methyl ester, using a base catalyst, to form the required glucamide (see Figure 13.15). 

These surfactants are produced by reacting fatty acids or fatty methyl esters with ethanolamine or diethanolamine. With fatty acids, conventional amides (sometimes called Kritchevsky alkanolamides) are obtained that consist of approximately 50% amide, 25% unreacted diethanolamine and 25% of various by-products (the amine ester the amide ester, and the amine soap). With methyl esters, higher-active (90% amide) alkanolamides are produced these are known as super amides . 

Basically, the polyglycerol ethers are oligo ethers from glycerol, where the hydroxyl groups in the 1 and 3 position of the glycerol moiety is etherified. The enzymatic synthesis of polyglycerol fatty acid esters as a transesterification from the fatty methyl esters has been described (16). Lipozyme is used as catalyst and no solvent is needed. 

Hama, I., Okamoto, T., Nakamura, H. 1995. Preparation and properties of ethoxylated fatty methyl ester nonionics. J. Am. Oil Chem. Soc. 72 781-784. 

Other synthetic applications of the phosphazene bases include the use of Bu -Pl (37) in the alkylation of adenine in solution or solid phase, and the catalytic esterification of various glycerol derivatives with fatty methyl esters at room temperature. On occasions, the action of the phosphazene bases may promote processes that other proton abstractors do not, such as the observed rearrangement of (43) to the flavone (44) in the presence of (40e) (OBn = benzoyloxy). Patented process, include the purification " and assembly of polyhedral oligomeric silsesquioxane monomers, and the catalytic activation of silylated nucleophiles. ... 

Piazza JG, Nunes A, Foglia TA. Epoxidation of fatty acids, fatty methyl esters, and alkenes by immobilized oat seed peroxygenase. J Mol Catal B Enzym 2003 21 143-151. 

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