Methyl ester fatty acid

Filtration through an acidic filter aid or siUca removes the last traces of soap from the oil. The finished oil is heated under vacuum to remove small amounts of fatty acid methyl esters. 

Amides can be produced from fatty acid methyl esters by reaction with ammonia at 220 °C at 12.4 MPa (1800 psi) pressure. Reaction times are reduced to 1 h by this route however, the fatty acid feedstocks must fkst be converted to methyl esters (21). 

Regular fatty acid diethanolamides are prepared by heating fatty acid with diethanolamine at 160—180°C for 2—4 h. Superamides are prepared by heating a fatty acid methyl ester with an equimolar amount of diethanolamine at 100—110°C for 2—4 h the methanol formed is distilled off (Table 23). 

Sorbitol is the most important higher polyol used in direct esterification of fatty acids. Esters of sorbitans and sorbitans modified with ethylene oxide are extensively used as surface-active agents. Interesteritication of fatty acid methyl esters with sucrose yields biodegradable detergents, and with starch yields thermoplastic polymers (36). 

The catalytic hydrogenation of esters is of great commercial importance. It is one of the industrial methods used to produce long-chain fatty alcohols (eg, dodecyl and decyl alcohols) from fatty acid methyl esters (33). The method is also suitable for the conversion of dimethyl 1,4-cyclohexanedicarboxylate [94-60-0] into 1,4-cydohexanedimethanol [105-08-8] an important intermediate in the manufacturing of polyesters. 

Apply sample solution, then 12% methanoUc po- [7] tassium hydroxide solution, keep moist with methanol for 5 min. Fatty acid methyl esters are produced, triglycerides do not react. 

Scheme 5.1-70 Cracking and isomerization of fatty acids and fatty acid methyl esters in...

Fatty acids and fatty acid methyl esters... 

Hydrogenation of Fatty Acid Methyl Esters The hydrogenolysis of fatty acid methyl esters into the corresponding fatty alcohols and methanol is performed at 200-300°C and a H2 pressure of 200-300 bar with the aid of copper oxide/chromium oxide catalysts (Adkins catalysts). Three different procedures are applied [39 a-c] ... 

E. Fatty Acids and Fatty Acid Methyl Esters... 

The C10-C,8 fatty acids and fatty acid methyl esters, important intermediates for the production of surfactants, are almost exclusively produced by hydrolysis or a transesterification reaction of animal or vegetable fats and fatty oils. 

The transesterification of fats and fatty oils by methanol into fatty acid methyl esters proceeds at 50-70°C without pressure. The deacidified fat is stirred for a short period with an excess of methanol and 0.1-0.5% caustic alkali as catalyst. On standing the reaction mixture separates forming a bottom layer of glycerin and a top layer of fatty acid esters. 

Schmid et al. studied in detail the sulfonation reaction of fatty acid methyl esters with sulfur trioxide [37]. They measured the time dependency of the products formed during ester sulfonation. These measurements together with a mass balance confirmed the existence of an intermediate with two S03 groups in the molecule. To decide the way in which the intermediate is formed the measured time dependency of the products was compared with the complex kinetics of different mechanisms. Only the following two-step mechanism allowed a calculation of the measured data with a variation of the velocity constants in the kinetic differential equations. 

FIG. 1 Critical micelle concentration as a function of the number of carbon atoms in the hydrophobic rest of sodium a-sulfo fatty acid methyl esters. Methods O, surface tension +, conductivity A, solubilization of a dye x, solubility (all without electrolyte) , surface tension with a constant electrolyte concentration of 5 x 10"2 mol/L. (From Ref. 57.)... 

Fujiwara et al. used the CMC values of sodium and calcium salts to calculate the energetic parameters of the micellization [61]. The cohesive energy change in micelle formation of the a-sulfonated fatty acid methyl esters, calculated from the dependency of the CMC on the numbers of C atoms, is equivalent to that of typical ionic surfactants (Na ester sulfonates, 1.1 kT Ca ester sulfonates, 0.93 kT Na dodecyl sulfate, 1.1 kT). The degree of dissociation for the counterions bound to the micelle can be calculated from the dependency of the CMC on the concentration of the counterions. The values of the ester sulfonates are also in the same range as for other typical ionic surfactants (Na ester sulfonates, 0.61 Ca ester sulfonates, 0.70 Na dodecyl sulfate, 0.66). 

Fujiwara et al. studied the precipitation phase boundary diagrams of the sodium salts of a-sulfonated myristic and palmitic acid methyl esters in the presence of calcium ions [61]. The time dependency of the precipitation showed that the calcium salts have an extremely slow crystallization rate at room temperatures. This is the reason for the good hardness tolerance of the a-sulfonated fatty acid methyl esters. 

A soap-based powder can be produced in combination with ester sulfonates. Thirty-five percent of a sodium soap mixture (5% lauric acid, 5% myristic acid, 52% palmitic acid, 21% stearic acid, 12% oleic acid, and 5% linoleic acid) is mixed with 15% sodium a-sulfo palm oil fatty acid methyl ester, 3% lauric acid ethoxylate, 5% sodium silicate, 17% sodium carbonate, 20% Na2S04- 10H2O, and 5% water [79]. 

A phosphate-free detergent with excellent detergency and improved foaming and rinsing properties consists of 10% sodium a-sulfo hardened beef tallow fatty acid methyl ester, 10% sodium dodecyl sulfate, 5% a-sulfomyristic acid disodium salt, 10% zeolite, 10% sodium silicate, 10% sodium carbonate, 10% cellulose, 40% Flauber s salt, and 4% water [80]. 

A heavy granular detergent can be produced by mixing a detergent composition with powdered or granular sodium carbonate. A typical detergent comprises 8% sodium a-sulfo hardened palm oil fatty acid methyl ester, 2% di-Na a-sulfopalmitate, 10% Na coconut oil alcohol sulfate, 2% polyethylene... 

For an enzyme-containing detergent the enzyme is added to a detergent composition with esters and disalts of a-sulfo fatty acids. The detergent granular comprises 7 % sodium a-sulfo hardened palm oil fatty acid methyl ester, 5% disodium salt of a-sulfo hardened palm oil fatty acid, 10% sodium a-olefin (C14 18) sulfonate, 10% zeolite, 5% sodium carbonate, 5% water, and 55% sodium sulfate [82]. 

A detergent, imparting better flexibility to cotton cloth is produced by adding 1% sodium a-sulfo hardened tallow fatty acid methyl ester and 9% disodium a-sulfo hardened palm oil fatty acid to a mixture of 5% sodium n-dodecyl-benzenesulfonate, 5% a-C16-olefmsulfonate, 3% dimethyldistearylammonium chloride, 15% zeolite, 10% sodium silicate, 10% sodium carbonate, 2% soap, 35% Na2S04-7H20, and 5% water [84],... 

D. a-Sulfo fatty acid methyl esters (methyl ester sulfonates) 634... 

The chemistry of fatty acid methyl ester (FAME) sulfonation is complicated and not yet fully elucidated, but it may be summarized as depicted in the following reaction scheme. The initial reaction between FAME and S03, although fast, is far from instantaneous. Two intermediate products are formed ... 

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