Alcohol from Molasses

The most important conversions in the context of green chemistry is with the help of enzymes. Enzymes are also referred to as biocatalysts and the transformations are referred to as biocatalytic conversions. Enzymes are now easily available and are an important tool in organic synthesis. The earliest biocatalytic conversion known to mankind is the manufacture of ethyl alcohol from molasses, the mother liquor left after the crystallisation of cane sugar from concentrated cane juice. This transformation is brought about by the enzyme invertase which converts sucrose into glucose and fructose and finally by the enzyme zymase which converts glucose and fiuctose into ethyl alcohol. It is well known that most of the antibiotics have been prepared using enzymes (enzymatic fermentation). 

A plant for the fermentation of sulfite waste liquor in America was built at Mechanicsville, New York, by the West Virginia Pulp and Paper Company in 1914. The alcohol stills and some of the other equipment were imported from Germany and were considered the most modern at that time. In comparison to present American stills, these were very inefficient because they were wasteful of steam and did not recover all the alcohol. This plant reused the yeast from a previous fermentation for succeeding fermentations. The plant produced about 221,000 gallons of alcohol per year in 1919. In later years, because of the inefficiency of the alcohol stills with dilute alcohol solutions, molasses was added to the sulfite waste liquor to increase the alcohol content. The plant operated until 1939, when it was closed because of obsolescence. 

Methylamine occurs in herring brine 2 in crude methyl alcohol from wood distillation,3 and in the products obtained by the dry distillation of beet molasses residues.4 It has been prepared synthetically by the action of alkali on methyl cyanate or iso-cyanurate 5 by the action of ammonia on methyl iodide,6 methyl chloride,7 methyl nitrate,8 or dimethyl sulfate 9 by the action of methyl alcohol on ammonium chloride,10 on the addition compound between zinc chloride and ammonia,11 or on phos-pham 12 by the action of bromine and alkali on acetamide 13 by the action of sodamide on methyl iodide 14 by the reduction of chloropicrin,15 of hydrocyanic or of ferrocyanic acid,16 of hexamethylenetetramine,17 of nitromethane,18 or of methyl nitrite 19 by the action of formaldehyde on ammonium chloride.20... 

Method 2B Preparation of 95% ethyl alcohol from table sugar, brown sugar, molasses, or... 

Potassium chloride, KC1.—The chloride is found in nature as sylvine in combination as carnallite, KCl,MgCl2,6H20 kainite, KCl,MgS04,3H20 and as douglasite, K2FeCl4,2H20. It is also a constituent of the ashes of plants, and of the residues from the manufacture of alcohol from beet-molasses. 

Aqueous solutions of these alcohols occur when sugar solutions are fermented and may be separated by distilling the mixtures. It is a common, economically valuable process for manufacturing potable liquors and for producing industrial alcohol from fermented molasses solutions or pulp mill wastes. One of the authors (A.Y.M.) reports that design and operation of these columns is hampered by lack of vapor-liquid equilibrium data, especially for making potable liquors, where small amounts of the alcohols other than ethanol greatly affect the flavor and, therefore, the products marketability. 

In industry ethyl alcohol is widely used as a solvent for lacquers, varnishes, perfumes, and flavorings as a medium for chemical reactions and in recrystallizations. In addition, it is an important raw material for synthesis after we have learned more about the reactions of alcohols (Chap. 16), we can better appreciate the role played by the leading member of the family. For these industrial purposes ethyl alcohol is prepared both by hydration of ethylene and by fermentation of sugar from molasses (or sometimes starch) thus its ultimate source is petroleum, sugar cane, and various grains. 

With a faint smell of alchemical heritage, the European fine fragrance industry, by contrast, uses in the main alcohol derived from molasses. Being natural, this alcohol has the combination of an odour, a slight inconsistency of quality and a living essence of its own, which is highly valued in an industry which places uniqueness and character on a high pedestal. 

In the manufacture of alcohol from cane molasses, the molasses iB diluted, properly acidified, and balanced by adding a nitrogenous compound, usually ammonium sulphate, for the purpose of supplying the yeast with a nitrogen supply. 

New and enlarged uses for the amyl alcohols and their derivatives, particularly in pyroxylin lacquers, have called for enlarged production, which could not remain dependent upon incidental fusel oil from molasses and potatq fermentation. This new production has come from the pentanes of natural gasoline through the chlorination-hydrolysis process developed by Ayres. ... 

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. 

Kopsahelis N., Agouridis N., Bekatorou A. and Kanellaki M. Comparative study of spent grains and delignified spent grains as yeast supports for alcohol production from molasses. Bioresource Technology 98 (7) (2007) 1440-1447. 

Constitaent of fusel oil A mixture of isoamyl alcohol and amyl alcohol in raiying amounts, depending on the source (potatoes, molasses, etc.). That from potato contains 13-22% of the active alcohol, that from molasses 50-60%. B.p. 130-2°. 0-81. Sol. H 0. 

There has been a steady increase in the production of alcohol in India, with the estimated production rising from 887.2 million litres in 1992-1993 to nearly 1654 million litres in 1999-2000. Surplus alcohol leads to depressed prices for both alcohol and molasses. The projected alcohol production in the country increased from 1869.7 million litres in 2002-2003 to 2300.4 million litres in 2006-2007. Thus, the surplus alcohol available in the country was expected to go up from 527.7 million litres in 2002-2003 to 822.8 million litres in 2006-2007 (Tables 6.23 and 6.24, Figure 6.21). 

---