Composition of natural oils

Three important attributes of the structure of these fatty acids are The length of the fatty chain, the degree of unsaturation (number of 

The chain length of fatty acids can vary from to but Cjj is the 

The double bonds in the chain are the reactive centers responsible for thermal and oxidative polymerization properties of the oils. A quantitative measure of the average degree of unsaturation present in a given oil is expressed by its iodine value (IV), which increases with an increasing number of double bonds. Therefore, highly unsaturated oils having the ability to form a solid or semisolid polymeric structure by means of oxidative or thermal polymerization are invaluable for coatings. 

In addition to the number of double bonds, their placement in the fatty chain with respect to each other also has a considerable influ- 

Certain oiis contain characteristic fatty acids, such as ricinoleic acid in castor oii, with hydroxyoieic acid (12-hydroxy-9-octadecenoic acid) eieostearic acid in tung oil, with a conjugated triene licanic acid in oiticica oil, with a conjugated triene keto acid, which are responsibie for the high reactivity of the parent oils. 

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Menthol 0.003-0.015% in suspensions, and syrups Cooling effect Sublimes easily above 25° C and composition of natural oil may vary with source Incompatible with thymol, phenol, camphor, and other excipients Slightly soluble in glycerin very soluble in alcohol... 

The majority of surfactants for detergents have optimal carbon chains between C12 and C18, depending on the attributes required. From an examination of the composition of natural oils shown in Figure 4.15, it is apparent that the choice of oils is limited. 

Table 9.1.2 Fatty acid compositions of natural oils and fats. ... 

Nearly all the commercially important fats and oils of animal and plant origin consist almost exclusively of this simple lipid class. The fatty acid composition can vary enormously. In seed oils, the Cis unsaturated fatty acids tend to predominate. In animal fats, especially those of adipose tissue origin, the fatty acid composition reflects that of the diet to some extent, but Cie and Cis fatty acids are the most abundant components. Fish triacylglycerols and those of marine mammals differ from others in that they contain a high proportion of C20 and C22 polyunsaturated fatty acids. The compositions of natural oils and fats have been reviewed recently [686]. 

Table 2. Fatty Acid Compositions of Naturally Occurring Fats and Oils ...

The main commercial source of methane, ethane, and propane is natural gas, which is found ia many areas of the world ia porous reservoirs they are associated either with cmde oil (associated gas) or ia gas reservoirs ia which no oil is present (nonassociated gas). These gases are basic raw materials for the organic chemical industry as well as sources of energy. The composition of natural gas varies widely but the principal hydrocarbon usually is methane (see Gas, natural). Compositions of typical natural gases are Hsted ia Table 2. 

Asphalt Roofing Components. Asphalt (qv) is a unique building material which occurs both naturally and as a by-product of cmde-oil refining. Because the chemical composition of cmde oils differs from source to source, the physical properties of asphalts derived from various cmdes also differ. However, these properties can be tailored by further ptocessiag to fit the appHcation for which the asphalt will be used. Softening poiat, ductility, flash poiat, and viscosity—temperature relationship are only a few of the asphalt properties that ate important ia the fabricatioa of roofing products. 

Asphalts are usually specified in several grades for the same industry, differing in hardness or viscosity (95). However, with the changing nature and composition of cmde oil feedstocks over the past two decades, performance and supply factors are also an important consideration (95). 

Alcohols used in the manufacture of alcohol and alcohol ether sulfates are obtained either by chemical treatment of fats and oils or by petrochemical processes from natural gas or crude oil. In either case the hydrocarbon chain ranging from 8 to 18 carbon atoms corresponding to the composition of coconut oil is the most desirable. 

Natural ingredients based lipstick formulations have been prepared. The effects of the natural waxes, oils and solvent compositions on the viscosity and melting point of the lipstick have been studied. The result indicates that the viscosity and melting point of the lipstick can be manipulated by changing the composition of natural candelilla wax, camauba wax and beeswax in the formulation. Another important lipstick characteristic, which is hardness, will be studied. Consumer acceptance towards the product will be investigated. Finally, by relating the consumer data and instrumentation analysis, optimisation process will be conducted. 

Sorensen Studies Related to Naturally Occurring Acetylene Compounds. XI. Further Investigations on the Composition of Essential Oils from the Genus Erigeron. Acta Chem. Scand. 7, 1375 (1953). 

Any composition of crude oil depends on the combination of various factors. Among the environmental factors, those that influence the nature of the organic matter in the source rock and its mineral composition are of primary significance. 

Ravid U, Putievsky E, Weinstein V, Ikan R, Determination of the enantiomeric composition of natural flavouring agents by H-NMR spectroscopy, in Baerheim Svendsen A, Scheffer JJC (eds.). Essential Oils and Aromatic Plants, Martinus Nijhoff/Dr. W. Junk Publishers, Dordrecht, The Netherlands, pp. 135-138, 1985. 

The composition of natural gas varies with the source, but essentially is made up of methane, ethane, propane, and other paraffinic hydrocarbons, along with small amounts of hydrogen sulfide, carbon dioxide, nitrogen, and. in some deposits, helium. Natural gas is found underground at various depths and pressures, as well as in solution with crude-oil deposits. Principal gas deposits are found in the United States, Canada, the former Soviet Bloc, and the Middle East. The analysis of a gas sample taken from the Panhandle natural gas field in Texas is given in Table 1. Because numerous parts of the earth do not have natural gas at all, or where supply is less than demand, much natural gas is transported, notably by pipeline in the gaseous or liquid phase and across the seas in specially-designed LNG (liquefied natural gas) earners. 

In order to understand the composition of heavy oils and residua, it is necessary to present a very brief description of the constituents of the lower boiling fractions of petroleum. Acceptance that petroleum is a continuum of molecular types that continues from the low-boiling fractions to the nonvolatile fractions (Speight, 1999 and references cited therein) is an aid to understanding the chemical nature of the heavy feedstocks. 

Composition The chemical composition of natural essential oils can be tremendously variable. A typical composition for this material may be 1,8-cineole 70-90°/o, with a-pinene, af-limonene, poro-cymene, a-phellandrene, camphene, a-terpinene. 

Although most of the oils tested in this study show a similar solubility behavior, significant differences can occur, depending on the composition of the oils with respect to their hydrocarbon fraction and the chemical nature and the amount of additives. With the specifications given by the producers like density and viscosity at standard conditions (see Table 1) no correlation could be found to the experimental data. Further information about the composition is hardly available and an exact analysis is not only undesired but also nearly impossible. This lack of information also makes phase equilibrium calculations to be not very useful for the correlation or prediction of these solubility data. In every single case the solubility has to be determined experimentally. 

Because of the ease of qualitative analysis, first through distillation to isolate major components and, subsequently, through GLC, volatile oils have consistently attracted the attention of chemotaxonomists. These oils are almost invariably complex mixtures in which monoterpenes and/or sesquiterpenes usually predominate, although the bios)mthetically unrelated phenylpropanes can also be important. Some of the earliest studies on the genetic control of SM involved the oils of mints, Mentha (Murray, 1960). Volatile oils yielded the first properly documented examples of chemical races (Penfold and Morrison, 1927 Sutherland and Park, 1967), while Zavarin and co-workers (1971) provided clear evidence for the impact of environmental factors on the composition of volatile oil. Because of the comparative nature of GLG analysis, volatile oils were among the first compounds to be extensively studied at the population level and to be subjected to numerical analysis. The work of Adams on Juniperus in south-eastern USA... 

This chapter considers the composition of heavy oils in terms of a map of molecular weight vs. polarity of the various components in the sample. Thus, a clearer understanding of the nature of asphaltenes is obtained. The inter-relationship of polarity and molecular weight in terms of solubility behavior can be better understood and it becomes clear that there is not a specific chemical composition or a specific molecular weight description for asphaltenes. Rather, asphaltenes contain a wide distribution of polarities and molecular weights. 

Typical examples of the first approach, upgrading or improving the fiiel, are the catalytic removal of sulfur and aromatic compounds in automotive fuels [8,9]. A shift from the use of coal to the use of natural gas as a fuel in many industrial applications has led to reduced emissions, due to the favorable composition of natural gas as compared to coal. However, future developments of combustion processes will most likely include the use of more low-grade fuels, such as heavy fuel oils [10]. The use of coal will increase again, which can be related to its relative abundance. Finally, low-Btu fuels, such as gasified biomass or gasified coal will play an important role [11]. 

It should be noted that considerable variation in the chemical composition of natural menthol oils can occur depending upon their country of origin. The EINECS number for menthol is 201-939-0. 

Figure 10. Composition of shale oil, natural bitumen present at depth, and pooled oil, which are all derived from lower Jurassic shales, Paris Basin.

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