Unsaponifiables

The term naphthenic acid, as commonly used in the petroleum industry, refers collectively to all of the carboxyUc acids present in cmde oil. Naphthenic acids [1338-24-5] are classified as monobasic carboxyUc acids of the general formula RCOOH, where R represents the naphthene moiety consisting of cyclopentane and cyclohexane derivatives. Naphthenic acids are composed predorninandy of aLkyl-substituted cycloaUphatic carboxyUc acids, with smaller amounts of acycHc aUphatic (paraffinic or fatty) acids. Aromatic, olefinic, hydroxy, and dibasic acids are considered to be minor components. Commercial naphthenic acids also contain varying amounts of unsaponifiable hydrocarbons, phenoHc compounds, sulfur compounds, and water. The complex mixture of acids is derived from straight-mn distillates of petroleum, mosdy from kerosene and diesel fractions (see Petroleum). 

In the initial black Hquor concentration, saponified fatty and resin acid salts separate as tall oil soaps (see Tall oil). These soaps can be skimmed from the aqueous spent Hquor, acidified, and refined to give a cmde tall oil composed of resin acids, chiefly abietic and neoabietic fatty acids, chiefly oleic and Hnoleic and an unsaponifiable fraction made of phytosterols, alcohols, and hydrocarbons. Tall oil is fractionated primarily into fatty acids (see... 

Black Liquor Soap Recovery. Black Hquor soap consists of the sodium salts of the resin and fatty acids with small amounts of unsaponifiables. The soap is most easily separated from the black Hquor by skimming at an intermediate stage, when the black Hquor is evaporated to 25% soHds (7). At this soHds level, the soap rises in the skimmer at a rate of 0.76 m/h. At higher soHds concentrations, the tall oil soap is less soluble, but higher viscosity lowers the soap rise rate and increases the necessary residence times in the soap skimmer beyond 3—4 hours. The time required for soap recovery can be reduced by installing baffles, by the use of chemical flocculants (8,9), and by air injection into the suction side of the soap skimmer feed pump. Soap density is controUed by the rate of air injection. Optimum results (70% skimmer efficiency) are obtained at a soap density of 0.84 kg/L (7 lb/gal). This soap has a minimum residual black Hquor content of 15% (10—12). 

The alcohol fraction is likewise a complex mixture of both aUphatic and cycHc compounds (Table 10). The principal components are cholesterol (34%), and lanosterol and dihydrolanosterol (38%). The aUphatic alcohols account for about 22% of the unsaponifiable products. Sixty-nine components of ahphatic alcohols had been reported up to 1974 (latest reported work as of ca 1997). The hydrocarbons (ca 0.5%) show stmctural similarity to the wool—wax acids or ahphatic alcohols and contain highly branched alkanes as well as cycloalkanes. 

Distillation. Most fatty acids are distilled to produce high quaHty products having exceUent color and a low level of impurities. Distillation removes odor bodies and low boiling unsaponifiable material in a light ends or heads fraction, and higher boiling material such as polymerized material, triglycerides, color bodies, and heavy decomposition products are removed as a bottoms or pitch fraction. The middle fractions sometimes can be used as is, or they can be fractionated (separated) into relatively pure materials such as lauric, myristic, palmitic, and stearic acids. 

Suitable organic solvents, such as ether, benzene, naphtha and the like, are more soluble than in water. This makes it possible to separate them from other substances which may accompany them in the water solution but which are not soluble in the solvents employed. Hence, one application of solvent extraction is the analytical determination of unsaponifiable oils and waxes in admixture with fatty material by submitting the mixture to vigorous saponification with alcoholic potash or, if necessary, sodium ethylate, and to dilute the product with water and extract with petroleum ether. The soaps remain in the aqueous solution while the unsaponifiable oils and waxes dissolved in the ether. The addition of a salt to an aqueous solution prior to extraction is sometimes practiced in some processes. In older processes, SOj is employed in the separation of aromatic and highly saturated hydrocarbons, taking advantage of the much greater solubility of the solubility of the aromatics and... 

For this purpose 10 c.c. of oil are saponified for one hour with 20 c.c. of 2/N alcoholic potash. 25 c.c. of water are then added and the bulk of the alcohol evaporated off. The solution is then almost neutralised to phenolphthalein and the unsaponified oil removed by shaking out three times with ether. 

We always recommend that structural changes occurring after the saponification procedure be verified. Since the hydroxyl groups have no influence on the chromophore, the wavelength of the maximum absorption, shape, and intensity of the ultraviolet-visible (UV-Vis) spectrum would be identical for unsaponified and saponified samples. 

Fatty acids (palmitic, oleic, linoleic acids) from unsaponifiables Silicalite-1 Acetone [179]... 

Lipids are important components of the diet fatty acids are the higher energetic source as they ensure 9kcal/g. Furthermore, some peculiar fatty acids themselves and several components of the unsaponifiable fraction are biologically active molecules, as they can act as vitamins (tocopherols— vitamin E), provitamins (carotenes—vitamin A, cholecalcipherol—vitamin D), vitamin-like (essential fatty acids), and hormones or hormone precursors (sterols—steroidal hormones). 

Estrogenic effect. Unsaponifiable fraction of the seed oil, administered subcutaneously to immature female rats at a dose of 117 mg/ animal, was inactive "A Subcutaneous administration to ovariectomized female guinea pigs was active . 

Oxygen radical inhibition. Seed oil, administered to rats at a concentration of 8% of diet, was active on macrophages. Gapsai-cin or curcumin enhanced the effecG. Phagocytosis stimulation. Ethanol (95%) extract and unsaponifiable fraction of the dried leaf, administered intraperitoneally to male mice at a dose of 0.5 mL/animal, were inactive . 

Heiduschka, A. Unsaponifiable matter of sesame oil. Orig Com 8th Intern Congr Appl Chem 1912 11 13. 

Tall Oil Fatty acids and some unsaponifiable material obtained as a major byproduct from the sulfite-pulping process of wood. 

The chemistry for providing steroid raw materials from the far more readily available soybean sterols was developed somewhat later. The so-called unsaponifiable fraction... 

Sterols. These compounds are found in the unsaponifiable fraction of milk lipids and consist mostly of cholesterol with some lanosterol. Methods for the determination of unsaponifiables using dry saponifica-... 

Flanagan, V. P. and Ferretti, A. 1973. Hydrocarbons and polychlorinated biphenyls from the unsaponifiable fraction of anhydrous milk fat. J. Lipid Res. 14, 306-311. 

Maxwell, R. J. and Schwartz, D. P. 1979. A rapid, quantitative procedure for measuring the unsaponifiable matter from animal, marine, and plant oils. J. Am. Oil chem. Soc. 56, 634-636,... 

Tall oil is a byproduct obtained from the manufacture of paper pulp from pine trees. It is separated by vacuum distillation (50 mm Hg) in the presence of steam into four primary products. In the order of decreasing volatility these are unsaponifiables (US), fatty acid (FA), rosin acids (RA), and pitch (P). Heat exchangers and rcboilers are heated with Dowtherm condensing vapors. Some coolers operate with water and others generate steam. Live steam is charged to the inlet of every reboiler along with the process material. Trays are numbered from the bottom of each tower. 

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