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Phenol is hazardous to health. The effect of phenol on the human body in case of poisoning. Chronic phenol poisoning

The largest quantities of phenol are used to obtain phenol-formaldehyde resins, which are used in the production of phenolic plastics. Large quantities of phenol are converted to cyclohexanol, which is essential for the synthetic fiber industry. A mixture of cresols is used to prepare cresol-formaldehyde resins. Pure cresols are used for the synthesis of dyes, medicines, antiseptic agents, and antioxidants.

Application in medicine:

When a large dose of phenol was introduced into the stomach, the latter was found in the contents of the stomach, in the blood, in the liver, kidneys, in the spleen, in the muscles and in the urine. Undesirable side effects can develop even after medical doses of phenol, namely, a mild headache is often observed, sometimes dizziness, a feeling of intoxication or stunnedness, a feeling of creeping creeps, increased sweating and general fatigue. But when taken internally large quantities signs of poisoning are characterized by: severe headache, dizziness, fainting, tinnitus, pallor, nausea, vomiting, loss of strength, irregular breathing and low pulse; urine in mild cases of poisoning, as well as after medical doses taken for a long time, is colored dark, which depends on the transition of a significant amount of phenol introduced into the body into hydroquinone, which, upon further oxidation, gives colored compounds. Severe cases of poisoning are characterized by unconsciousness, cyanosis, difficulty breathing, numbness of the cornea, rapid, barely perceptible pulse, cold sweat, a decrease in temperature, and often convulsions. If, after the introduction of phenol through the mouth, vomiting appears, then the vomit has a phenol odor; urination in most cases is upset, urine contains protein, in rare cases there is blood pigment in the urine - so-called hemoglobinuria is observed. In rare cases, after such symptoms, a fairly rapid recovery of strength was observed, in the vast majority of cases, despite the consciousness returning from time to time, death occurs very quickly due to difficulty breathing and an extreme decline in cardiac activity. Burns of the mucous membrane produced by phenol rarely penetrate the muscular layer of the latter, and they usually do not occur below the duodenum; sometimes limited and diffuse bruises were found in the first pathways of the alimentary canal, in other cases the mucous membrane acquired a harder consistency, resembling tanned leather. The stomach contains brown coagulated blood, the intestines are covered with blood mucus; pulmonary edema was often observed; in the kidneys, hyperemia, swelling of the cortical substance, blood blockages in the cortical substance and fatty degeneration of the renal epithelium are found. The possibility of fatal phenol poisoning after topical application of large amounts to intact skin has been proven by both human observations and experimental studies on animals. A case of death is described after smearing the skin against scabies with a concentrated solution of phenol. By the end of the rubbing, there was a burning sensation in the skin, a feeling of dizziness and severe deafness, delirium and complete loss of consciousness, after which death soon followed. As an antidote for poisoning with phenol introduced internally, based on experiments on animals, caustic lime with sugar was proposed (5 hours of caustic lime are dissolved in 40 hours of water, 60 hours are added to the solution). cane sugar, then the mixture is filtered and evaporated to dryness at temp. 100 °). The combination of lime with phenol is difficult to dissolve and therefore is less toxic. The drug should be prescribed in the first minutes after poisoning, since phenol is very quickly absorbed from the stomach. Among the antidotes, mention should be made of lime water, carbon dioxide, and crushed chalk. In addition, useful: gastric lavage, stimulants and especially useful to warm the patient.

Phenol, extracted by Runge from coal tar in 1834, was already known at that time as an antiseptic agent, but this remedy found wide application in medicine only from the late 1860s. last century, when the famous English surgeon Lister used phenol to heal wounds and for the doctrine of antiseptics that he created.

Pharmachologic effect. Carbolic acid solutions (3-5%) cause coagulation of the dissolved protein; phenol has the same effect on glue solution, on milk, albumin and casein of which coagulate from 5% phenol solution. With putrefactive proteins, carbolic acid, apparently, forms a strong chemical compound, since it cannot be opened in a coagulated liquid, unless it has been added in excess. Red blood globules, when directly affected by 3-4% phenol solutions, gradually shrink, the coloring matter is separated from the stroma; the drug has the same destructive effect on purulent balls, on muscle and nerve fibers. It has been proven that 1-2% phenol solutions destroy molds; solutions 1: 500 stop the development of fungi; 1-2% solutions reduce the ability of yeast cells to ferment grape or milk sugar, stronger solutions (4-5%) completely destroy the vital activity of these cells. Bacteria that cause decay of organic substances are not so easily affected by phenol; this requires the action of more concentrated solutions and a longer action; so a solution of 1: 200 only delays the development of putrefactive microorganisms; to destroy the ability to reproduce the latter, a concentration of 1:25 is required. On anthrax spores, 1% solutions (according to Koch) do not work even for 15 days; 2% delay development after about 10-20 hours; 3% cause, after 3 days, free gaps in the wiring, but the spores are killed after 7 days; A 4% solution gives the same effect on the third day, and 5% on the second day (it should be noted that carbolic acid in an alcoholic or oil solution does not even have a weak anti-putrefactive effect when microorganisms are outside the body or on artificial nutrient media). Erysipelas resist the action of a 1% phenol solution for only 60 seconds; diphtheria rods show a decrease in growth within 30 seconds; yellow pyogenic cluster resists the 5-minute action of 1% and the 15-second action of the 2nd solution; microorganisms of typhoid and cerebrospinal meningitis were more resistant; glanders sticks, chain coccus of maternity fever were destroyed by 3% carbolic solution in 15-60 seconds. On unorganized enzymes, carbolic acid acts to a much lesser extent: the addition of phenol in 1/2% of the mixture of saliva and sugar does not affect the physiological properties of saliva. The conversion of protein into peptones under the influence of digestive juice seems to be delayed and even completely stopped by the action of 1/2% or stronger solution, which is explained by changes physical properties protein, namely by coagulation and difficulty in converting it into acidalbumin. The formation of hydrocyanic acid under the action of emulsin on amygdalin is only temporarily stopped by a 4% solution, reappearing after dilution of the phenol solution.

Therapeutic uses. Lubrication with concentrated solutions causes whitening of the skin, a sensation of pain; the white spot consists of a very unstable combination of carbolic acid with the tissue of the upper skin; skin areas become 3-5 percent after lubrication. solutions, due to the soaking of carbolic acid on the sensitive endings, insensitive, they experience a feeling of numbness for several hours. These properties of carbolic acid are based on its external use in weak solutions as a pain reliever and in concentrated solutions as a cauterizing and destructive substance. Due to its anti-putrefactive properties, phenol is widely used for the disinfection of objects and rooms in which harmful bacteria can remain after infectious patients, as well as for the anti-putrefactive method of treating wounds; for the same purpose, dressings (gauze, cotton wool, yuta, etc.) are still impregnated with phenol solutions, although the "anti-rot" method is now trying to replace the "aseptic" method, that is, a method in which microorganisms are not allowed to the wound as it produces better results. In case of burns, lubrication with a 1-2% phenol solution has an anti-rotting effect, relieves pain and limits the separation of the ulcerative surface; local anesthesia when using alcoholic or ether solutions is more pronounced than from oil or glycerin solutions. Phenol is prescribed internally, usually in pills, at 0.02-0.04 several times a day, against abnormal fermentation or putrefaction in the stomach or intestines, then also with the same processes in the respiratory organs, and in such diseases inhalations turned out to be useful 1-2% phenol solution, but also oral administration gives some improvement in putrid bronchitis, with gangrene of the lungs. Undoubtedly, the use of phenol for disinfection of the patient's wards and secretions, his linen, home, etc. % phenol).

The use of phenols. The phenol solution is used as a disinfectant (carbolic acid). Diatomic phenols - pyrocatechol, resorcinol (Fig. 3), as well as hydroquinone (para-dihydroxybenzene) are used as antiseptics), tibacterial disinfectants), are introduced into the composition of tanning agents for leather and fur, as stabilizers of lubricating oils and rubber, as well as for processing photographic materials and as reagents in analytical chemistry.

In the form of individual compounds, phenols are used to a limited extent, but their various derivatives are widely used. Phenols serve as starting compounds for the preparation of various polymer products - phenolic resins (Fig. 7), polyamides, polyepoxides. On the basis of phenols, numerous drugs are obtained, for example, aspirin, salol, phenolphthalein, in addition, dyes, perfumery products, plasticizers for polymers and plant protection products.

Lysol is used for skin disinfection. Resorcinol is used for skin diseases (eczema, seborrhea, itching, fungal diseases) externally in the form of solutions (water and alcohol) and ointments. Benzonaphthol, antiseptic for diseases of the gastrointestinal tract. Adults are prescribed 0.3-0.5 g 3-4 times a day. Children under 1 year old - 0.05 g per reception, under 2 years old - 0.1 g, 3-4 years old - 0.15 g, 5-6 years old - 0.2 g, 7 years old - 0.25 g, 8 -14 years - 0.3 g.

CONCLUSION: Phenol compounds are very diverse, phenol and its compounds are widely used in industry and medicine.

PhenolС 6 Н 5 ОН - an artificial compound with a pungent characteristic odor.

Has a low melting point, is characterized by the ability to dissolve in organic and inorganic solvents.

At temperatures above 70 ° C, it dissolves in water in any ratio.

It is an industrial pollutant that is extremely toxic to humans and animals.

The negative effect of phenol on humans

When inhaled, phenol causes disturbances in the activity of the nervous and cardiovascular systems.
Vapors and phenol solution irritate the skin, mucous membranes of the respiratory tract and eyes, provoking chemical burns, and also affect internal organs, especially the kidneys and liver.
Once on the skin, phenol is quickly absorbed, even with intact skin, and after a few minutes it has an effect on the brain tissue.
First, there is a short-term excitement, and then - paralysis of the respiratory center.
Even small doses of phenol can cause coughing, sneezing, dizziness, headache, nausea, and loss of energy.
For severe cases of poisoning, unconsciousness, cyanosis of the skin and mucous membranes, cold sweat, numbness of the cornea, barely perceptible pulse, convulsions are characteristic.
Phenol often causes the development of cancer. Phenol does not lose over time toxic properties, and for a person its danger is not reduced.
If ingested, this extremely dangerous substance can cause muscle atrophy, ulcers, and internal bleeding.

The time for the withdrawal of phenol from the body is 24 hours, but during this period it is capable of causing irreparable harm to the body for many years. The lethal dose for an adult is 1-10 grams, for children 0.05-0.5 grams.

What are the standards for phenol in the air?

Phenol belongs to substances of II - high hazard class. Its standards in the ambient air are established to prevent, reduce or eliminate harmful effects on the human body.

At the same time, standards are established that are designed for a short period of exposure (maximum one-time concentration) and for a longer period (average daily concentration).

The maximum permissible concentration (MPC) of phenol in the ambient air is a concentration that does not have an indirect or direct adverse effect throughout life on the present or future generation, does not reduce performance and does not worsen a person's well-being and sanitary conditions of his life.

The maximum permissible maximum one-time in the air of populated areas is a concentration that, when inhaled for 20-30 minutes, should not cause reflex reactions in the human body. For phenol MPC MR = 0.01 mg / m³.

The maximum permissible average daily concentration of phenol in the air of populated areas is a concentration that should not have a direct or indirect negative effect on a person with indefinitely long inhalation. For phenol MPC CC = 0.003 mg / m³.

Phenol is a chemical organic matter, hydrocarbon. Other names are carbolic acid, hydroxybenzene. It is of natural and industrial origin. What is phenol and what is its significance in human life?

Origin of the substance, chemical and physical properties

The chemical formula of phenol is c6h5oh. In appearance, the substance resembles crystals in the form of needles, transparent, with a white tint. In the open air, when interacting with oxygen, the color becomes light pink. The substance has a specific smell. Phenol smells like gouache paint.

Natural phenols are antioxidants that are found in varying amounts in all plants. They determine color, aroma, protect plants from harmful insects. Natural phenol is good for the human body. It is found in olive oil, cocoa beans, fruits, nuts. But there are also poisonous compounds, for example, tannin.

The chemical industry produces these substances by synthesis. They are poisonous and highly toxic. Phenol is dangerous to humans, and the industrial scale of its production significantly pollutes the environment.

Physical properties:

phenol normally dissolves in water, alcohol, alkali;
has a low melting point, at 40 ° C turns into a gas;
in its properties it is very similar to alcohol;
has high acidity and solubility;
at room temperature are in a solid state;
the smell of phenol is sharp.

How phenols are used

More than 40% of substances are used in the chemical industry to obtain other organic compounds, mainly resins. Also from it artificial fibers - nylon, nylon. The substance is used in the oil refining industry to purify oils that are used in drilling rigs and other technological facilities.

Phenol is used for the production of paints and varnishes, plastics, chemicals and pesticides. In veterinary medicine, the substance on farms is used to treat animals of agricultural importance for the prevention of infections.

The use of phenol in the pharmaceutical industry is significant. It is part of many drugs:

antiseptics;
pain relievers;
antiplatelet agents (thin the blood);
as a preservative for the production of vaccines;
in cosmetology as part of preparations for chemical peeling.

In genetic engineering, phenol is used to purify DNA and isolate it from a cell.

Toxic effect of phenol

Phenol is a poison... By its toxicity, the compound belongs to the 2nd hazard class. This means that it is highly hazardous for the environment... The impact on living organisms is high. The substance can cause serious damage to the ecological system. The minimum recovery period from phenol exposure is at least 30 years, subject to the complete elimination of the source of contamination.

Synthetic phenol has a negative effect on the human body. The toxic effect of the compound on organs and systems:

Inhalation of vapors or swallowing affects the mucous membranes of the digestive tract, upper respiratory tract, eyes.
In contact with the skin, a phenol burn is formed.
With deep penetration, it causes tissue necrosis.
Has a pronounced toxic effect on internal organs. With kidney damage, it causes pyelonephritis, destroys the structure of red blood cells, which leads to oxygen starvation. It can cause allergic dermatitis.
Inhalation of phenol in high concentrations disrupts the work of brain activity, can lead to respiratory arrest.

The mechanism of the toxic action of phenols is to change the structure of the cell and, as a consequence, its functioning. The most susceptible to toxic substances are neurons (nerve cells).

Maximum permissible concentration (MPC of phenol):

the maximum single dose in the atmosphere for populated areas is 0.01 mg / m³, which is kept in the air for half an hour;
the average daily dose in the atmosphere for populated areas is 0.003 mg / m³;
the lethal dose in case of ingestion is for adults from 1 to 10 g, for children from 0.05 to 0.5 g.

Symptoms of phenol poisoning

The harm of phenol to a living organism has long been proven. Upon contact with the skin or mucous membranes, the compound is rapidly absorbed, overcomes the hematogenous barrier and is carried with the blood throughout the body.

The brain is the first to react to the effects of the poison. Signs of poisoning in humans:

Psyche. Initially, the patient experiences mild agitation, which lasts for a short time and is replaced by irritation. Then comes apathy, indifference to what is happening around, the person is in a depressed state.
Nervous system. General weakness, lethargy, and loss of strength are increasing. Tactile sensitivity is blurred, but the reaction to light and sounds is exacerbated. The victim feels nausea, which is not related to the functioning of the digestive system. Dizziness appears, the headache becomes more intense. Severe poisoning can lead to seizures and unconsciousness.
Skin. The skin becomes pale and cold to the touch, and in severe condition it acquires a blue tint.
Respiratory system. When even small doses enter the body, a person develops shortness of breath and rapid breathing. Due to irritation of the nasal mucosa, the victim has continuous sneezing. With moderate poisoning, a cough and spastic contractions of the larynx develop. In severe cases, the threat of spasm of the trachea and bronchi increases and, as a result, suffocation, leading to death.

Circumstances under which poisoning can occur - violation of safety rules when working with highly hazardous substances, drug overdose, household poisoning with detergents and cleaning agents, as a result of an accident.

If there is low quality furniture in the house, children's toys that do not meet international safety standards, the walls are painted with paint not intended for these purposes, then a person constantly inhales the outgoing phenol vapors. In this case, chronic poisoning develops. Its main symptom is chronic fatigue syndrome.

First aid principles

The first thing to do is to interrupt the person's contact with the poisonous source.

Take the victim out of the room into fresh air, unfasten buttons, locks, zippers to better provide oxygen access.

If phenol solution gets on your clothing, take it off immediately. Rinse the affected skin and mucous membranes of the eye repeatedly and thoroughly with running water.

If phenol gets into the mouth, do not swallow anything, but immediately rinse your mouth for 10 minutes. If the substance has managed to get into the stomach, you can drink the sorbent with a glass of water:

activated or white carbon;
enterosorb;
enterosgel;
sorbex;
carbolene;
polysorb;
lactofiltrum.

You cannot wash the stomach, as this procedure will increase the degree of the burn and increase the area of mucosal lesions.

The antidote to phenol is a solution of calcium gluconate for intravenous administration. In case of poisoning of any severity, the victim is taken to the hospital for observation and treatment.

It is possible to remove phenol from the body in a hospital with severe poisoning by the following methods:

Hemisorption is the purification of blood with a special sorbent that binds molecules of a toxic substance. The blood is purified by running it in a special apparatus.
Detoxification therapy - intravenous infusion of solutions that dilute the concentration of a substance in the blood and promote its natural excretion from the body (through the kidneys).
Hemodialysis - indicated in severe cases when there is a potential threat to life. The procedure is carried out using an "artificial kidney" apparatus, in which blood passes through special membranes and leaves molecules of a toxic substance. The blood returns to the body clean and rich in useful microelements.

Phenol is a synthetic poisonous substance that is dangerous to humans. Even a naturally occurring compound can be harmful to health. To avoid poisoning, it is necessary to take responsibility for work in production where there is a risk of contact with poison. When shopping, be interested in the composition of the product. The unpleasant smell of plastic products should alert you. When using medicinal products containing phenol, observe the prescribed dosage.

Allergy is considered the plague of the twenty-first century. More than a third of people in the world are affected by this disease. As soon as the allergen enters the body, antibodies appear.

Initially, harmless, passive antibodies, with the subsequent reintroduced allergen, combine with it in the cell membranes and rupture these membranes. Histamine molecules are released from the cells. They also cause skin diseases - urticaria, inflammation of the mucous membrane, lung disease - bronchial asthma. Violent antibody responses to allergens can lead to death. One of the main allergens is phenol.

Phenolic compounds are dangerously toxic. Especially if you inhale the toxic fumes of phenolic dust. Phenols freely enter the body from the air through the skin, lungs and stomach, causing the following allergic diseases: nasal edema - rhinitis, redness and painful swelling of the eyes - conjunctivitis, upper respiratory tract diseases - bronchospasm, shortness of breath and wheezing, asthma attacks ...
Ear disease - swelling, pain, and hearing loss may occur.

Skin diseases with allergies are manifested by eczema, urticaria, dermatitis. In some cases of allergy, a severe headache occurs. With a violent response of antibodies to phenol allergens, anaphylactic shock may occur - bronchospasm, edema.

A person, exposed to long-term exposure to carbolic acid, receives many, severe, often irreversible, diseases: allergies, diarrhea, mouth ulceration, toxic hepatitis. The gastrointestinal tract can be damaged, but the kidneys are most destroyed, as they remove phenol from the body.

With prolonged exposure to phenol, poisoning occurs, destruction nervous system and, as a result, paresis of the respiratory tract and death of brain cells may occur. That is why, if symptoms of an allergic reaction to phenol are detected, or if signs of phenol poisoning appear, such as a rash on the skin, a burning sensation in the mouth, vomiting, difficulty breathing or swallowing, the appearance of edema, you should immediately contact a medical facility.

Where phenol "hides": sources of infection

We have been living in a phenolic environment for a long time. The toxic composition can be found in building materials, carpets, clothing, toys and food. It is necessarily present in household chemicals. The presence of phenol can be noticed by the smell, sweetish, reminiscent of the smell of gouache, some say that the smell is "like in a pharmacy." It is the fumes of phenol, even at the most ordinary temperature, that cause allergies.

The main sources of phenol can be building materials such as some types of chipboard and fiberboard. The polymer material used to finish floors, walls, and decorative plastics used in finishing windows and doors can also be a source of phenol allergy.

From such items, phenol can be released for several years. Varnishes and paints in the apartment and plastic windows, baseboards, wall panels, any PVC products also often poison us with phenol: linoleum, laminate, vinyl wallpaper, and other floor coverings contain phenolic dyes. Phenol can be present in insulation: artificial "mineral wool", for example, is "famous" for the high content of this substance.

Furniture made of fiberboard and chipboard, when exposed to heat, is even more toxic than building materials. Decorative films, adhesives, upholstery materials, varnish and enamel used in the manufacture of furniture contain phenol.

Clothes from Bangladesh, Sri Lanka, Cambodia made from fabrics with dyes containing phenol are also very dangerous.

From home care products, the most allergenic dyes are all sorts of fragrances, as well as friable elements that create powder dust.

Cosmetics, like household chemicals, contain fragrances and preservatives, and these are phenol and other harmful substances to extend the shelf life.

Baby, mostly Chinese and from Taiwan, illegally made, are also sources of phenol. Phenols and formaldehyde in unacceptable concentrations are found in children's rubber, latex, plastic and soft toys. In the process of manufacturing such products, phenol is used to shape the plastic mass and rubber.

Smoke can be a source of phenol allergy. Cigarette smoke contains phenol as a disinfectant, along with other carcinogens.
When heated, plastic dishes release toxic substances, including phenol, poisoning the human body.

Phenol is found in drinking water and air.

Phenol-impregnated sofas, clothes, household appliances, dishes, toys, cosmetics, household chemicals can somehow be excluded, but most terrible of all are foods and medications containing phenol. The use of medicines and consumer products containing phenol exposes a person to a much higher level of poisoning.

A person swallows such drugs, rubs them or applies them to the skin. Numerous disinfectants, nasal, ear and herpes lotions, throat and mouthwash, toothache drops and antiseptic lotion all contain carbolic acid. Aspirin, antiseptics, and pharmacy pesticides are all phenolics.

The peel of oranges, apples, bananas treated with phenol-containing preparations prevents the fruit from rotting. Many other additives are also used in the food industry with good intentions in the manufacture, processing, conservation, disinfection, but almost all of them are poisonous and cause allergies if they contain phenol.

Types of phenol allergies

Allergy:

Allergy from odor and phenol particles in the air is respiratory. The reaction occurs when dust, pollen, gases, perfumery odors, in which phenol is present, enter the body from the air. The symptoms of a respiratory allergy are a runny nose accompanied by an itchy nose, a person sneezing and coughing.

Bronchial asthma is also referred to as allergic diseases. Allergic reactions - lacrimation, pain and itching in the eyes are caused by volatile phenols present in the air. With such an allergy, in contrast to colds, the body temperature does not rise. Phenolic compounds can kill a child suffering from bronchial asthma.

Contact allergy:

Statistics put in second place, after respiratory, contact allergies: dermatoses caused by the use of cosmetics, pharmaceuticals, household chemicals, latex. Symptoms of allergic dermatoses are a rash and itching on the skin. The skin turns red, swells, blisters and peeling appear. The rash is usually small, watery, like hives.

Respiratory allergies and contact dermatitis are usually recognized 15 years or more after inhalation or skin contact.

And allergies:

Drug and food allergies usually develop no more than a day. Signs of food allergies can be: allergic skin lesions, dermatitis, urticaria, Quincke's edema. In addition, gastrointestinal disorders - vomiting, nausea, diarrhea, constipation, flatulence and respiratory disorders - rhinitis, asthma.

Phenols are found in almost many foods, such as salicylates. Some children are unable to convert phenols into useful substances. Salicylates accumulate to the point that causes allergies. Some people cannot even tolerate the natural salicylates of healthy foods. The reaction to them, in especially sensitive ones, is as acute as when using synthetic additives.

With a drug allergy, the most severe case can occur - anaphylactic shock. A person loses consciousness, has difficulty breathing, the body is cramping, a rash on the body may appear. If you suspect the onset of anaphylactic shock, you should immediately call an ambulance. Anaphylaxis can develop within one minute to several hours from the beginning of contact with allergens.

The main danger of phenol

Phenol is a poison, in excessive doses, which causes irreversible damage to many organs. If it gets through the air, it can cause burns that can lead to pulmonary edema.

Phenol, a chemical of organic origin, belongs to the group of aromatic hydrocarbons.

In 1842, the French organic scientist Auguste Laurent was able to deduce the formula of phenol (C6H5OH), consisting of a benzene ring and a hydroxy group OH. Phenol has several names that are used both in scientific literature and in colloquial speech, and arose due to the composition of this substance. So, phenol is often called oxybenzene or carbolic acid.

Phenol is poisonous. Dust and phenol solution irritate the mucous membranes of the eyes, respiratory tract, and skin. Possesses weakly acidic properties, under the action of alkalis forms salts - phenolates. Under the action of bromine, tribromophenol is formed, which is used to obtain an antiseptic - xeroform. The benzene nucleus and the OH-group, combined in the phenol molecule, influence each other, significantly increasing each other's reactivity. Of particular importance are the reactions of condensation of phenols with aldehydes and ketones, as a result of which polymer products are obtained.

Physical properties of phenol

Chemical properties of phenol

Phenol is a white crystalline substance with a characteristic pungent sweetish-sugary odor, which easily oxidizes when interacting with air, acquiring at first a pinkish, and after a while a saturated brown color. A feature of phenol is its excellent solubility not only in water, but also in alcohol, alkaline media, benzene and acetone. In addition, phenol has a very low melting point and easily turns into a liquid state at a temperature of + 42 ° C, and also has weak acidic properties. Therefore, when interacting with alkalis, phenol forms salts called phenolates.

Depending on the production technology and purpose, phenol is produced in three grades: A, B and C in accordance with GOST 23519-93. Below are its technical characteristics.

Phenol technical characteristics according to GOST 23519-93

Indicator name	Meaning
Indicator name	Grade A	Grade B	Grade B
Appearance	White crystalline substance		White crystalline chesky in-in. Allowed pinkish or yellowish tint
Crystallization temperature, ° С, not lower	40,7	40,6	40,4
Mass fraction of non-volatile residue,%, no more	0,001	0,008	0,01
Optical density of an aqueous solution of phenol (8.3 g of grade A, 8.0 g of grade B, 5.0 g of grade C in 100 cm3 of water) at 20 ° С, no more	0,03	0,03	0,03
Optical density of sulfonated phenol, no more	0,05	Do not standardize
Chromaticity of the phenol melt by platinum-cobalt scale, Hazen units:
from the manufacturer, no more	5	Do not standardize
at the consumer:
during transportation by pipeline and in tanks made of stainless steel, no more	10	Also
during transportation in tanks made of carbon steel and galvanized, no more	20	>>
Mass fraction of water,%, no more	0,03	Do not standardize
Mass fraction of the sum of organic impurities,%, no more	0,01	Do not standardize
including mesityl oxide,%, no more	0,0015	0,004	Do not standardize
the amount of methylstyrene and isopropylbenzene (cumene),%, no more	Do not standardize	0,01	Also

Methods for obtaining phenol

Phenol does not occur in its pure form in nature; it is an artificial product of organic chemistry. Currently, there are three main methods for the production of phenol on an industrial scale. The bulk of its production falls on the so-called cumpole method, which involves the oxidation of aromatic organic compound isopropylbenzene. As a result of a chemical reaction, cumpol hydroperoxide is obtained, which, upon interaction with sulfuric acid, decomposes into acetone, followed by the precipitation of phenol in the form of a crystalline precipitate. Methylbenzene (toluene) is also used for production, as a result of the oxidation of which this chemical and benzoic acid are formed. In addition, in some industries, such as metallurgical coke, phenol is released from coal tar. However, this production method is unprofitable due to the increased energy consumption. Among the latest achievements of the chemical industry are the production of phenol by the interaction of benzene and acetic acid, as well as the oxidative chlorination of benzene.

For the first time in industrial volumes, phenol was obtained by the German company BASF in 1899, by sulfonating benzene with sulfuric acid. The technology of its production consisted in the fact that subsequently the sulfonic acid was subjected to alkaline melting, as a result of which phenol was formed. This method has been used for over 100 years, but in the second half of the 20th century, chemical enterprises were forced to abandon it due to huge amount waste sodium sulfite, which was a by-product of organic synthesis of phenol.

In the first half of the 20th century, the American company Dow Chemical introduced another method for the production of phenol, by chlorination of benzene, which was called the "Raschig process". The method turned out to be quite effective, since the specific gravity of the resulting substance reached 85%. Subsequently, the same company introduced a method for the oxidation of methylbenzene with the subsequent decomposition of benzoic acid, however, due to the problematic deactivation of the catalyst, today it is used by about 3-4% of chemical industry enterprises.

The most effective is the cumpole method for producing phenol, which was developed by the Soviet chemist Pyotr Sergeev and introduced into production in 1942. The first kumpolny plant, built in 1949 in the city of Dzerzhinsk, Gorky Region, was able to meet a third of the USSR's demand for phenol.

Scope of phenol

Initially, phenol was used for the production of various kinds of dyes, due to its property of changing color during oxidation from a pale pink to brown hue. This chemical is found in many types of synthetic paints. In addition, the property of phenol to destroy bacteria and microorganisms was adopted in the leather industry when tanning animal skins. Later, phenol was successfully used in medicine as one of the means of disinfection and disinfection of surgical instruments and premises, and as a 1.4% aqueous solution - as an analgesic and antiseptic for internal and external use. In addition, the phenol of salicylic acid is the basis of aspirin, and its derivative, paraaminosalicylic acid, is used to treat tuberculosis patients. Phenol is also part of the powerful laxative, purgen.

Currently, the main purpose of phenol is the chemical industry, where this substance is used for the manufacture of plastics, phenol-formaldehyde resins, such artificial fibers as nylon and nylon, as well as various antioxidants. In addition, phenol is used for the production of plasticizers, oil additives, and is one of the components that make up plant protection products. Phenol is also actively used in genetic engineering and molecular biology as a means for purifying and isolating DNA molecules.

Harmful properties of phenol

Almost immediately after receiving phenol, scientists found that this chemical has not only useful properties, which allows it to be used in various fields of science and industry, but is also a potent poison. So, inhalation of phenol vapors for a short time can lead to irritation of the nasopharynx, burns of the respiratory tract and subsequent pulmonary edema with a fatal outcome. When the phenol solution comes into contact with the skin, chemical burns are formed, which subsequently transform into ulcers. If more than 25 percent of the skin is treated with a solution, then this can cause death. The ingress of phenol into the body with drinking water leads to the development of peptic ulcer disease, muscle atrophy, impaired coordination of movements, and bleeding. In addition, scientists have found that it is phenol that is the cause of cancer, contributes to the development of heart failure and infertility.

Due to the property of oxidation, the vapors of this chemical completely dissolve in air after about 20-25 hours. When it gets into the soil, phenol retains its toxic properties throughout the day. However, in water, its viability can reach 7-12 days. Therefore, the most likely way for this poisonous substance to enter the human body and on the skin is contaminated water.

As a part of plastics, phenol does not lose its volatile properties, therefore, the use of phenolic plastics in the food industry, the production of household items and children's toys is strictly prohibited today. Their use is also not recommended for the decoration of residential and office premises, where a person spends at least a few hours a day. As a rule, phenol is excreted from the body with sweat and urine within 24 hours, but during this time it manages to cause irreparable damage to human health. Due to its harmful properties, in many countries of the world there are restrictions on the use of this substance for medical purposes.

Transportation and storage conditions

There are international standards for the transport of phenol, designed to avoid the release of the substance into the environment.

Phenol is transported by rail in accordance with the rules for the carriage of goods in tanks equipped with a heating device. Tanks shall be made of stainless chromium-nickel steel, zinc-coated carbon steel, or carbon steel. Phenol, intended for the production of medical products, is transported in railway tanks made of stainless chromium-nickel steel and zinc-coated carbon steel. Phenol is also transported through a heated pipeline made of stainless chromium-nickel steel.

Phenol in the molten and solid state is stored in sealed tanks made of stainless chromium-nickel steel, zinc-coated carbon steel, or carbon steel, as well as in monolithic aluminum containers. It is allowed to store phenol in a molten state under nitrogen (the volume fraction of oxygen in nitrogen should not exceed 2%) at a temperature of (60 ± 10) ° С for 2-3 days. when storing in aluminum containers, it is necessary to strictly control the temperature in order to avoid the dissolution of aluminum in the product.