Hydrocarbons, Alcohols, and Esters

Waxes are water-repelling solids that are part of the protective coatings of a number of living things, including the leaves of plants, the fur of animals, and the feathers of birds. They are usually mixtures of esters in which both the alkyl and acyl group are unbranched and contain a dozen or more carbon atoms. Beeswax, for example, contains the ester triacontyl hexadecanoate as one component of a complex mixture of hydrocarbons, alcohols, and esters. 

Egolf, L.M. and Jurs, P.C. (1992). Estimation of Autoignition Temperatures of Hydrocarbons, Alcohols and Esters from Molecular Structure. Ind.Eng.Chem.Res., 31,1798-1807. 

Figure 1. Changes in concentration of total monoterpene hydrocarbons, (- -) alcohols (-<>-) and esters (-X-) during ripening of Wellington XXX blackcurrants in 198U.

Accurate g.l.c. analysis of mixtures of substances with a flame ionization detector (f.i.d.) depends upon a knowledge of the relative detector response of each compound. Variations in the f.i.d. responses of steroids in molar terms have now been put on a quantitative basis. There is a good linear relationship between molar f.i.d. response and the effective carbon number , which is the number of carbon atoms per molecule less half the number of oxygen atoms (over the ranges Ci8—C31, and Oo—O4). This behaviour parallels earlier conclusions for paraffin hydrocarbons, alcohols, and esters. G.l.c. data are reported for the trimethylsilyl ethers of 49 plant sterols on eight different columns. ... 

Gas-liquid (GLC) and high-performance liquid (HPLC) chromatography are extremely useful techniques and are fully described in a later chapter. They are primarily used for quantitative analysis, GLC for more volatile and HPLC for less volatile substances. GLC can determine, for example, hydrocarbons, alcohols and esters, and HPLC can determine fatty acids and high-molecular-weight materials. Both can determine chain-length distributions of both hydrocarbon and ethylene oxide chains. It is frequently necessary to prepare derivatives of the materials to be separated by GLC, but this is not usually the case for HPLC. Neither is very useful as an aid to identification of unknowns. 

Unaffected by aromatic and aliphatic hydrocarbons, alcohols and esters service to 100°C more resistant to organic solvents than PVC low permeability to organic and aqueous chemicals. 

Sodium Dispersions. Sodium is easily dispersed in inert hydrocarbons (qv), eg, white oil or kerosene, by agitation, or using a homogenizing device. Addition of oleic acid and other long-chain fatty acids, higher alcohols and esters, and some finely divided soHds, eg, carbon or bentonite, accelerate dispersion and produce finer (1—20 -lm) particles. Above 98°C the sodium is present as Hquid spheres. On cooling to lower temperatures, soHd spheres of sodium remain dispersed in the hydrocarbon and present an extended surface for reaction. Dispersions may contain as much as 50 wt % sodium. Sodium in this form is easily handled and reacts rapidly. For some purposes the presence of the inert hydrocarbon is a disadvantage. 

Infrared Spectroscopy (ir). Infrared curves are used to identify the chemical functionality of waxes. Petroleum waxes with only hydrocarbon functionality show slight differences based on crystallinity, while vegetable and insect waxes contain hydrocarbons, carboxyflc acids, alcohols, and esters. The ir curves are typically used in combination with other analytical methods such as dsc or gc/gpc to characterize waxes. 

Esters are most commonly prepared by the reaction of a carboxyHc acid and an alcohol with the elimination of water. Esters are also formed by a number of other reactions utilizing acid anhydrides, acid chlorides, amides, nitriles, unsaturated hydrocarbons, ethers, aldehydes, ketones, alcohols, and esters (via ester interchange). Detailed reviews of esterification are given in References 1—9. 

Respiratory Effects. Hexane was one of 16 industrial solvents (hydrocarbons, alcohols, ketones, esters, and ethyl ether) tested for irritation potential on an average of 10 volunteers of mixed sexes for 3-5 minutes in an inhalation chamber (Nelson et al. 1943). The purity and the isomer composition of the hexane was not specified. Hexane was the only one of the 16 solvents which caused no irritation to the eyes, nose, or throat at the highest concentration tested (500 ppm). No odor was reported. 

P.Y.191 displays excellent solvent fastness in aliphatic and in aromatic hydrocarbons, as well as in the commonly used plasticizers. The pigment is almost completely fast to alcohols and esters but not to water, ketones and methylglycol. 

The chemical resistance is generally inferior to that of comparable polyethylenes and decreases when VA rises. EVAs are attacked by concentrated strong acids, halogens, oxidizing acids, chlorinated solvents, certain oxidants, aliphatic and aromatic hydrocarbons, alcohols, ketones, esters, and some others. 

Alcohols and esters, made not from olefins, but from saturated hydrocarbons in this case, pentanes, were next on the scene, with the production in 1926 of amyl alcohol by chlorination and caustic hydrolysis. And shortly thereafter thfe intentional chlorination of ethylene was undertaken to expand the output of ethylene dichloride, formerly obtained as a by-product of glycol manufacture. 

Correlation of Qrlgoras Grigoras [25] derived a simple linear correlation to estimate V °(cm3 mol-1) for liquid compounds, including saturated, unsaturated, and aromatic hydrocarbons, alcohols, acids, esters, amines, and nitriles ... 

In 1925, Fischer and Tropsch developed a process for producing a mixture of saturated and unsaturated hydrocarbons, and oxygenated products such as alcohols and esters by the reaction of synthesis gas (a mixture of CO and H2) using heterogeneous catalysts of Fe and Co (eq. 1.1) [1],... 

Fat- and oil-soluble dyes are also soluble in waxes, resins, lacquers, hydrocarbons, halogenated hydrocarbons, ethers, and alcohols, but not in water. It is not possible to differentiate clearly between them and the alcohol- and ester-soluble dyes. With the exception of blue anthraquinone derivatives, fat- and oil-soluble dyes are azo dyes, generally based on simple components. According to their degree of solubility they usually contain hydroxyl and/or amino groups, but not sulfonic acid and carboxylic acid groups. Examples of fat- and oil-soluble azo dyes are C.I. 

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