A Practical Handbook on the Distillation of Alcohol from Farm Products - F. B. Wright

Table II.—100 Volumes of Mixture at 59° F.

Alcohol.	Contraction	Alcohol.	Contraction	Alcohol.	Contraction
100	0.00	65	3.61	30	2.72
95	1.18	60	3.73	25	2.24
90	1.94	55	3.77	20	1.72
85	2.47	50	3.74	15	1.20
80	2.87	45	3.64	10	0.72
75	3.19	40	3.44	5	0.31
70	3.44	35	3.14

Alcohol is termed “absolute” when it has been deprived of every trace of water, and when its composition is exactly expressed by its chemical formula. To obtain it in this state it must be subjected to a series of delicate operations in the laboratory, which it would be impossible to perform on an industrial scale. In commerce it is known only in a state of greater or less dilution.

Alcohol possesses the power of dissolving a large number of substances insoluble in water and acids, such as many inorganic salts, phosphorus, sulphur, iodine, resins, essential oils, fats, coloring matters, etc. It precipitates albumen, gelatine, starch, gum, and other substances from their solutions. These properties render it an invaluable agent in the hands of the chemist.

Alcohol is found in, and may be obtained from, all substances—vegetable or other—which contain sugar. As stated above, it does not exist in these in the natural state, but is the product of the decomposition by fermentation of the saccharine principle contained therein; this decomposition yields the spirit in a very dilute state, but it is readily separated from the water with which it is mixed by processes of distillation, which will subsequently be described. The amount of alcohol which may be obtained from the different unfermented substances which yield it varies considerably, depending entirely upon the quantity of sugar which they contain.

Alcohol is produced either from raw materials containing starch, as potatoes, corn, barley, etc., or raw materials containing sugar, as grapes, beets, sugar-cane, etc.

The following are some of the most important sources from which alcohol is obtained: Grapes, apricots, cherries, peaches, currents, gooseberries, raspberries, strawberries, figs, plums, bananas, and many tropical fruits, artichokes, potatoes, carrots, turnips, beet-root, sweet corn, rice and other grains. Sugar-cane refuse, sorgum, molasses, wood, paper, and by a new French process from acetylene. On a large scale alcohol is usually obtained from sugar beets, molasses or the starch contained in potatoes, corn and other grains. The starch is converted into maltose by mixing with an infusion of malt. The maltose is then fermented by yeast. Sulphuric acid may be used to convert even woody fibre, paper, linen, etc., into glucose, which may in turn be converted into alcohol.

Table III.—Principal Alcohols.

Chemical Name.			Source.			Formula.	Boiling Point °F.
1	Methyl	Alcohol	Distillation of Wood			CH₃OH	150.8
2	Ethyl	“	Fermentation	of	sugar	C₂H₅OH	172.4
3	Propyl	“	“	“	grapes	C₃H₇OH	206.6
4	Butyl	“	“	“	beets	C₄H₉OH	242.6
5	Amyl	“	“	“	potatoes	C₅H₁₁OH	278.6
6	Caproyl	“	“	“	grapes	C₆H₁₃OH	314.6
7	Aenanthyl	“	Distillation castor oil with potatoes			C₇H₁₅OH	347.0
8	Capryl	“	Essential oil hog weed			C₈H₁₇OH	375.8
9	Nonyl	“	Nonane from petroleum			C₉H₁₉OH
10	Rutyl	“	Oil of Rue			C₁₀H₂₁OH
11	Cytyl	“	Spermaceti			C₁₆H₃₃OH
12	Ceryl	“	Chinese wax			C₂₆H₅₃OH
13	Melisyl	“	Bees’ wax			C₃₀H₆₁OH

Among a variety of other substances which have been and are still used for the production of alcohol in smaller quantities, are roots of many kinds, such as those of asphodel, madder, etc. Seeds and nuts have been made to yield it. It will thus be seen that the sources of this substance are practically innumerable; anything, in fact, which contains or can be converted into sugar is what is termed “alcoholisable.”