Ethyl alcohol: general information, methods of preparation and application

Alcohols are derivatives of hydrocarbons, in the molecule of which one or more hydrogens are replaced by a hydroxyl group (OH). Lower alcohols dissolve in all proportions in water. With acids, alcohols form ethers. Hydrogen hydroxyl group can be replaced. So, with the action of metallic sodium, alcoholates are formed. In the process of hydrolysis, alcoholates decompose to water and caustic soda.

Primary alcohols oxidize well to form aldehydes. Aldehydes are organic compounds that do not have OH groups and do not give esters; With further oxidation break down into acids with a smaller number of carbon atoms. In the process of dehydration of alcohols , unsaturated hydrocarbons are obtained. On the body, aliphatic alcohol alcohols act, in general, narcotically. The strength of the action of alcohol depends on their physical properties. When comparing one- and polyhydric alcohol, it is noted that the effect of the latter is weakened, and sometimes completely lost, i.e. An increase in the number of hydroxyls in the molecule reduces the pharmacological effect, for example, glycerol has no noticeable narcotic effect.

Preparation of ethyl alcohol

Alcohol for medical purposes is obtained by fermenting sugary substances. Carbohydrates of rye, potatoes, maize, and other plant materials are subjected to fermentation. A number of intermediate stages of alcoholic fermentation are known today . At the distillery, the incoming material (potatoes, etc.) is first washed from the ground and dirt, and then loaded into a special pail, where steam is released under pressure in two or three atmospheres. Starch, which is in potatoes, turns into a paste. The resulting mass is transferred to the mash tank and there, with energy stirring, is cooled to 50 degrees. Malt is added to it at a concentration of up to 10% of the weight of the potato. Malt is prepared by germination of barley. During the germination of barley in the grains there is a process of formation and accumulation of enzymes, one of which is the amylase enzyme. This enzyme hydrolyses the starch to maltose. Maltose is then converted into glucose under the influence of the enzyme invertin in an aqueous medium. The latter under the influence of winters turns into ethyl alcohol with the release of carbon dioxide. The process is considered complete when the release of carbon dioxide is stopped. The resulting liquid is called a bob, which contains about 18% alcohol and various intermediate fermentation products - glycerol, ethanal (acetate aldehyde), higher alcohols, ethers, etc. Then the mash is subjected to rectification. First, a mixture with an alcohol content of about 70% is obtained, then the level of the latter is increased to 96%. Ethyl alcohol for final purification is passed through activated carbon.

It is economically advantageous to produce alcohol synthetically - from ethylene, which, when sulfate reacts, gives sulfatoethyl ether, decomposed by the action of water on ethyl alcohol and sulfate acid. It should be noted that alcohol can be synthesized from acetylene. For this purpose, acetylene is passed through an aqueous solution of sulfate acid, in the presence of a catalyst, it attaches water, passing into ethanol. Aldehyde is distilled and reduced with hydrogen to alcohol. The alcohol concentration is expressed in degrees, for example, 33 °, 40 °. These degrees indicate how much alcohol is contained in 100 volume units of this solution.

There are the following types of alcohol:

- raw (92-95 °), not sufficiently purified from fusel oils and aldehydes;

- rectified (95-96 °), practically free of impurities;

- Absolute - practically waterless;

- denatured - raw alcohol, to which natural pyridine nitrogen bases have been added; Used for technical and domestic purposes.

Ethyl alcohol is a flammable transparent liquid that has a neutral reaction, an alcoholic smell and a burning taste. Pure alcohol is a good organic solvent. The density of ethyl alcohol depends on its concentration in solutions (for example, 40-0.9352, 70-0.8677, 96-0.8014).

The use of ethanol

Weaken or kill microorganisms, especially at concentrations above 60-70%. The drug activates digestion, reflexively enhances the activity of the respiratory center and heart during fainting. External applied as a disinfectant, irritant, cooling and refreshing in the treatment of burns (I and II degree) remedy.