How to get alcohol?

There are many ways to obtain food andtechnical alcohols. These methods can be divided into two groups: chemical and biochemical. In this case, synthetic alcohols (technical) are produced with the help of the first ones, and with the help of the latter, bio-alcohols (food).

How to get alcohol by fermentation

Wine or ethyl alcohol can be obtained by differentchemical and biochemical methods. The oldest and most common method is alcoholic fermentation followed by dehydration (removal of water).

It is quite difficult to obtain an ethylalcohol by fermentation, in which yeast participates. It has been established that fermentation is provoked not by yeast itself, but by specific substances released by them - zymazy. During the fermentation of glucose C₆H₁₂ABOUT₆ is converted into alcohol and carbonic acid by the following equation:

• FROM₆H₁₂ABOUT₆ → 2СО₂ + 2C₂H₅OH + energy

where CO₂ - Carbon dioxide, and C₂H₅OH is ethyl alcohol.

Alcohol fermentation can not only beglucose, but also other sugary substances contained in nature as plant components (for example, in juice). What is the result of alcohol in this case? From potatoes, beets, wheat grains, oats, rice, etc.

If raw materials are used to obtain alcohol,rich in starch, it must first succumb to saccharification - the transformation of starch into sugar under the action of certain enzymes. In this case, the reaction is carried out according to the following formula:

• (FROM₆H₁₀ABOUT₅)_n + nH₂O + ENZY → nC₆H₁₂ABOUT₆

where (C₆H₁₀ABOUT₅)_n - starch.

After converting the starch into sugar furtherto get ethyl alcohol from glucose is much easier. If the sugar is used for obtaining alcohol, the process is reduced to fermenting the processed sugary juice.

Fermented raw materials are distilled by the processrectification. To do this, the alcohol-containing liquid is heated (brought to a boil). When boiling, alcohol evaporates and enters the distillation column, and then into the reflux condenser. In the dephlegmator, the vapors come into contact with the cooled surface, condense, draining into a container, and form a liquid alcohol.

Hydration of ethylene

Alcohol can be obtained from ethylene (gas) in the presence of concentrated strong acid (phosphoric, sulfuric). The process is carried out in an autoclave. Sulfuric acid hydration occurs according to this scheme:

• FROM₂H₄ + H₂SO₄ → C₂H₅ABOUT₂-SO₂
• H₃C-CH₂-O-SO₂OH + H-O-H → H₃C-CH₂-OH + H₂SO₄

The total equation is:

• H₂C = CH₂ + H₂О → Н₃C-CH₂-OH (in the presence of sulfuric acid H₂SO₄)

Other methods of obtaining alcohols

How to get alcohol from an alkane (its halogen derivative)? A reaction is needed here, which occurs by the type of hydrolysis. As a result, ethyl alcohol and sodium chloride are formed:

• FROM₂H₅CI + NaOH → C₂H₅OH + NaCl

To obtain alcohol from ketones or aldehydes,it is necessary to carry out the reaction of ethynylation of these compounds (another name is Favorsky's reaction). In this reaction, ketones, alkynes and aldehydes (most often formaldehyde) enter the reaction in the basic medium (eg, in KOH). The reaction proceeds according to this scheme:

• RC≡CH + CH₂O → RC≡C-CH₂OH
• HC≡CH + 2CR₂O → HOCR₂-C≡C-CR₂OH

where R is the radical C_nH_{2n + 1}

How to get alcohol from the ether by hydrolysis? It is worth knowing that hydrolysis per se is a chemical process in which, under the action of water, the decomposition (decomposition) of the starting materials with the formation of new compounds takes place. The hydrolysis of esters with the formation of alcohols occurs according to the following equation:

• RO-OR + NaOH → RO-ONa + HO-R

Where:

• R is the radical C_nH_{2n + 1}
• R is the radical C_nH_{n + 2}
• RO-OR - ether
• NaOH is sodium hydroxide
• RO-ONa - sodium carboxylate
• HO-R - alcohol

From acetic acid, alcohol can be obtained in several ways.

• Hydrogenation of acid: CH₃COOH + 2H₂ → H₂O + C₂H₅OH (the process takes place in the presence of nickel or platinum)
• Reduction of acetic acid derivatives (or other carboxylic acids): CH₃COOH + C₂H₅OH → CH₃-CO-O-C₂H₅ + H₂O (in the presence of sulfuric acid, an ester-ethyl acetate is formed). CH₃-CO-O-C₂H₅ + Na [C₂H₅OH] → C₂H₅OH + C₂H₅ONa
• Direct reduction of acetic or other acids to the production of alcohol is possible by reaction with lithium aluminum hydride. Here is the final equation of the process: 4CH₃-COOH + LiAlH₄ → 4CH₃-CH₂-OH + Al (OH)₃ + LiOH

The described methods (from alkanes, acids, ketones, aldehydes and other starting materials) produce technical alcohol. Food alcohol from various raw materials is obtained only by fermentation.