Propyl alcohol water miscibility

The student will doubtless be aware of the fact that methyl, ethyl, n-propyl and iso propyl alcohols are completely miscible with water. The solubilities of the higher aloohols decrease progressively as the carbon content increases. The solubilities of all types of alcohols with five carbon atoms or more are quite small. For the isomeric butyl alcohols the solubilities (g. per 100 g. of water at 20°) are n-butyl, 8 iso-butyl, 23 scc.-butyl, 13 ierl.-butyl, completely miscible. 

Propyl alcohol [71-23-8J, 1-propanol, CH2CH2CH2OH, mol wt 60.09, is a clear, colorless liquid having a typical alcohol odor it is miscible ia water, ethyl ether, and alcohols. 1-Propanol occurs ia nature ia fusel oils and forms from fermentation and spoilage of vegetable matter (1). 

Solvent manufacturer Honeywell Burdick Jackson [39] defines solvents as miscible if the two components can be mixed together in all proportions without forming two separate phases. A solvent miscibility chart (Figure 2.12) is a useful aid for determining which solvent pairs are immiscible and would therefore be potential candidates for use in LLE. More solvent combinations are miscible than immiscible, and more solvents are immiscible with water than with any other solvent. Solvents miscible with water in all proportions include acetone, acetonitrile, dimethyl acetamide, N,N-dimethylformamide, dimethyl sulfoxide, 1,4-dioxane, ethyl alcohol, glyme, isopropyl alcohol, methanol, 2-methoxyethanol, /V-methyI pyitoI idone. n-propyl alcohol, pyridine, tetrahydrofuran, and trifluoroacetic acid [40]. 

Use and exposure Propyl alcohol is a clear, colorless, volatile, flammable, fragrant liquid miscible with water and used as a solvent and antiseptic. It has two isomers n-propyl alcohol and isopropyl alcohol. These alcohols have extensive use as chemical intermediates in a variety of industries— manufacturing, pharmaceuticals, perfumes, cosmetics, skin lotions, hair tonics, mouthwashes, and liquid soaps. They are also used as lacquers, dental lotions, polishers, and surgical antiseptics. - ... 

The case in which two layers are formed, with its accompanying maximum of pressure, leads to the third, in which completely miscible liquids, such as propyl alcohol and water, give a maximum of pressure for a definite composition as shown by he d. From this consideration it is... 

Propyl hydroxid—Ethyl carbinol—Primary propyl alcohol— CH3,CH2,CH,0H—60—is produced, along with ethylic alcohol,dur-ing fermentation, and obtained by fractional distillation of marc brandy, from cognac oil, huile de marc (not to be confounded with oil of wine), an oily matter, possessing the flavor of inferior brandy, which separates from marc brandy, distilled at high temperatures and from the residues of manufacture of alcohol from beet-root, grain, molasses, etc. It is a colorless liquid, has a hot alcoholic taste, and a fruity odor boils at 96°.7 (306°.l F.) and is miscible with -water. It has not been put to any use in the arts. Its intoxicating and poisonous actions are greater than those of ethyl alcohol. It exists in small quantity in cider. 

Methanol and water are miscible in all proportions so too are mixtures of ethanol and water and mixtures of both propyl alcohols and water. In these cases the alkyl groups of the alcohols are relatively small, and the molecules therefore resemble water more than they do an alkane. Another factor in understanding their solubility is that the molecules are capable of forming strong hydrogen bonds to each other ... 

Methanol, ethanol, both propyl alcohols, and rerr-butyl alcohol are completely miscible with water (Table 11.1). The solubility of alcohols in water gradually decreases as the hydrocarbon portion of the molecule lengthens long-chain alcohols are more alkanelike and are, therefore, less like water. 

The vapour pressures of many pairs of infinitely miscible liquids have been determined by several experimenters and, as with the changes of volume and of temperature on mixing the liquids, so with the vapour pressures of the mixtures, very different results are obtained in different cases. There can be no doubt that the behaviour of mixtures, as regards vapour pressure, depends on the relative attraction of the like and the unlike molecules. When the mutual attraction of the unhke molecules is not much more than sufficient to cause infinite miscibility—for example, with normal propyl alcohol and water—the vapour pressure, like that of a partially miscible pair of liquids, may bo greater than that of either component at the same temperature. On the other hand, when that attraction is relatively very great (formic acid and water) the vapour pressure of the mixture may be less than that of either component. It seems reasonable to suppose that, when the attractions of the like and unlike molecules are equal or nearly so, the relation between vapour pressure and composition should be a simple one, and tbe question what is the normal behaviour of mixtures has been discussed by several investigators. 

When, however, we come to mixtures of n-propyl alcohol and water, we find that there is a very well defined maximum pressure, although the liquids are miscible in all... 

If the alcohol is present as the only volatile constituent in aqueous solution, the ordinary methods of alcohol determination may be applied, although Aiyar and Krishnan have recommended the following modification of the Thorpe and Holmes separation (Process B Appendix I) when the presence of zVopropyl alcohol is suspected. They found that both iso-propyl alcohol and w-propanol are miscible with light petroleum, that they have only limited solubilities in saturated sodium chloride solution and that both alcohols can be removed from light petroleum by water to a much larger extent than by saturated brine. 

CH3CH2CH2OH 1-Propanol Propyl alcohol, n-propanol 97-98 Miscible with water. 

Liquid. Slight odor resembling menthol. Pure Decalin does not smell of naphthalene. Volatile with steam. The commercial product may be practically all tram-Decalin, or a mixture contg up to 60% cis-Decalin. The commercial mixture has a flash pt (closed cup) of about 136 F (58 0. Autoignition temp 504 F. lnsol in water very sol in alcohol, methanol, ether, chloroform. Miscible with propyl and isopropyl alcohol miscible with most ketones and esters. LDM orally in rats 4.2 g/kg. Lethal conen for rats in air 500 ppm, Smyth er al.. Arch. Ind. Hyg Occup. Med. 4, 119 (1951). 

Ketones are solvents of moderate polarity. Like ethers, they are hydrogen bond acceptors and have dipole moments intermediate between those of ethers and alcohols. Ketones have a wide range of solubilities with water, from acetone being miscible, to methyl ethyl ketone (2-butanone) being soluble at 27%, to methyl propyl ketone (2-pentanone) being soluble to the 6% level. The higher molecular weight ketones are soluble to the 2% level or less. Ethyl acetate is soluble at the 9% level. 

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