Stearate methyl

In a series of organic acids of similar type, not much tendency exists for one acid to be more reactive than another. For example, in the replacement of stearic acid in methyl stearate by acetic acid, the equilibrium constant is 1.0. However, acidolysis in formic acid is usually much faster than in acetic acid, due to higher acidity and better ionizing properties of the former (115). Branched-chain acids, and some aromatic acids, especially stericaHy hindered acids such as ortho-substituted benzoic acids, would be expected to be less active in replacing other acids. Mixtures of esters are obtained when acidolysis is carried out without forcing the replacement to completion by removing one of the products. The acidolysis equilibrium and mechanism are discussed in detail in Reference 115. 

A similar reaction occurs with fatty acids (such as stearic acid) or methyl stearate, which undergo isomerization, cracking, dimerization, and oligomerization reactions. This has been used to convert solid stearic acid into the more valuable liquid isostearic acid [102] (Scheme 5.1-70). The isomerization and dimerization of oleic acid and methyl oleate have also been found to occur in chloroaluminate(III) ionic liquids [103]. 

A powdered soap-based laundry detergent contains 44% tallow soap, 18% sodium salt of a-sulfonated 1 1 methyl stearate-methyl palmitate mixture, 9% sodium silicate, 10% Na2S04, 2.5% ethoxylated cocoethanolamide, 1.4 cellulose, 0.2% fluorescent whitener, 0.7% enzyme, 0.5% perfume, and 5% water [77]. 

As anticipated, SA conversion increases with increasing residence time (1/LHSV) and with increasing temperature to a maximum of about 98%. This limit is most likely caused by equihbrium. This limit and thus the equilibrium constant were not affected by the temperature range studied, consistent with a low heat of reaction. The sum of the molar heats of combustion of stearic acid (11320 kJ/mol) and methanol (720 kJ/mol) is almost the same as the heat of combustion of methyl stearate (12010 kJ/mol), meaning that the change in enthalpy of this reaction is nearly zero and that the equihbrium constant is essentially temperature independent. 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

Larva Increases acceptance of queen cells Methyl stearate 80 [149] ... 

Methyl-2-(3-pyridyl)pyrrolidine, nl 9 Methyl pyruvate, m3 5 5 Methyl stearate, m346... 

Fig. 2.135. Upper lane HPLC chromatogram of all-rran.v /l-carolcnc and its isomers in the presence of Chl-a and methyl stearate during illumination for 3h. Peak identification 1 = 13,15-cis-ji-carotene 2 = 15-cw-/fcarotene 3 = a 11 -1 ra ns - /1-c aro tc n c 4 = 9-c(.v-/l-carolene 5 = 13-cis-ji-carotene. Lower lane HPLC chromatogram of Chl-a and its isomers in the presence of /1-carotene and methyl linoletae during illumination for 3 h. Peak identification 1 = Chl-a isomer I 2 = Chl-a isomer II 3 = Chl-a 4 = Chl-a. Chromatographic conditions are described in text. Reprinted with permission from B. H. Chen et al. [306].

Aliphatic ketones, alcohols, and esters (fenchone methyl stearate) accumulator column 7 49-94... 

Methyl stearate Methyl esters of three other 53.1 39 0A... 

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