The invention relates to the production and use of elemental sulfur, namely to the development of new effective solvents for elemental sulfur. The proposed system and hydrazine hydrate-amine in a molar ratio of 1:0.05-0.5. The highest dissolution of sulfur (1344 g/l) is observed in the presence of primary amines at a molar ratio of N 2 H 4 H 2 O:AMIN = 1: 0.5. 1 table

The invention relates to the production and use of elemental sulfur, namely to the development of new effective solvents for elemental sulfur. Tri- and tetrachlorethylene are used as solvents for elemental sulfur, as well as some petroleum products: AR-1, ethylbenzene fraction (EBF), pyrolysis resin - PS. The disadvantages of these solvents are their low efficiency and high dissolution temperatures (above 80 o C). There is a known method for quickly dissolving elemental sulfur in containers and pipelines by treating with dialkyl disulfides containing 5-10 parts of aliphatic mono-, di- or triamine (US Patent N 4239630, 1980) and. The disadvantage of this method is the use of expensive disulfides. Their use is also limited due to the unpleasant odor and the impossibility of regeneration from such sulfur solutions. There is a method for dissolving sulfur in aqueous solutions of NaOH to form Na 2 Sn. The highest solubility of sulfur is achieved at 80-90 o C and high NaOH concentration (30-60%). The disadvantages of this method are high dissolution temperatures, significant consumption of sulfur for side reactions of its oxidation and losses associated with this, high consumption of alkali and the corrosive effect of the resulting solutions. The purpose of the invention is to increase the efficiency of the sulfur dissolution process and eliminate the corrosive effect of sulfur solutions. This goal is achieved by using a new hydrazine hydrate-amine system as a solvent for elemental sulfur. Triethylamine, triethanolamine, morpholine and monoethanolamine were used as amines. The dissolution of elemental sulfur in the hydrazine hydrate-amine system proceeds exothermically - the reaction mass is heated to 60-65 o C. The amount of dissolved sulfur depends on the nature of the amine used and its concentration in the hydrazine hydrate solution (table). In 1 liter of hydrazine hydrate in the presence of amines, 700-1344 g of sulfur is dissolved. The highest dissolution effect is exhibited by primary amines - monoethanolamine. An increase in the molar fraction of amine in a hydrazine hydrate solution from 5 to 50% leads to an increase in the amount of dissolved sulfur in the system by approximately 1.5 times. As a result of the dissolution of sulfur in the hydrazine hydrate-amine system, dark red solutions are formed that are stable when stored under normal conditions. When diluted with water, the resulting solutions quickly eliminate sulfur, which is released by filtering aqueous suspensions. Hydrazine hydrate dissolves sulfur even without the addition of amines, but a significant amount of it is spent on the formation of hydrogen sulfide, which promotes the decomposition of hydrazine to ammonia. The proposed method for dissolving elemental sulfur has the following advantages. 1. Absence of alkali in the dissolving system. 2. The hydrazine hydrate-amine solvent system does not cause corrosion of metal surfaces. 3. Higher efficiency of the dissolution process: at low amine concentrations, more sulfur dissolves in the hydrazine hydrate-amine system than in the hydrazine hydrate-alkali system. 4. High dissolution rate under mild conditions. 5. Ease of implementation and manufacturability of the process for industrial use. 6. Obtaining storage-stable sulfur solutions that are suitable for use in industrial organic synthesis and in various industries, for example, in the pulp and paper industry. The method is illustrated by the following examples. Examples 1-10 (the results are shown in the table). The dissolution of sulfur is carried out in an experimental setup consisting of a four-neck flask equipped with a stirrer, a reflux condenser, a thermometer and a hole for introducing sulfur. A solution of the amine is prepared in a flask in 50 ml of hydrazine hydrate (concentrations are given in the table), and while stirring, sulfur is introduced in portions as it dissolves until a saturated solution is obtained. During the process of dissolving sulfur, the temperature of the solution rises to 60-65 o C. Dissolution is completed after 1 hour. When cooled, dark red sulfur solutions remain homogeneous and are stored for a long time without decomposition. The table shows the conditions and results of sulfur dissolution in the developed new systems. Example 11 (for comparison). In a similar manner, the dissolution of sulfur is carried out in pure hydrazine hydrate in the absence of an amine. 32 g of sulfur is dissolved in 50 ml of hydrazine hydrate, which in terms of 1 liter is 640 g or 20 mol/l, i.e. less than in the presence of amine (see table). When diluted with water, sulfur solutions are destroyed and most of the sulfur precipitates.

Claim

A method of dissolving elemental sulfur by treating it with a solvent, characterized in that a mixture of hydrazine hydrate and amine, taken in a molar ratio of 1 0.05 0.5, respectively, is used as a solvent.

Grosse E., Weissmantel H.

Chemistry for the curious. Basics of chemistry and entertaining experiments.

Sulfur vapor reacts with hot coal to form carbon disulfide CS 2 (carbon disulfide), a flammable liquid with an unpleasant odor. It is indispensable in the production of artificial silk and staples. Sulfur, which is known to be insoluble in water and dissolves in small quantities in benzene, alcohol or ether, is perfectly soluble in carbon disulfide.
If you slowly evaporate a solution of a small amount of sulfur in carbon disulfide on a watch glass, you will obtain large crystals of the so-called orthorhombic or α-sulfur. But Let's not forget about the flammability and toxicity of carbon disulfide, so let’s turn off all the burners and place the watch glass under the draft or in front of the window.
Another form is monoclinic, or β-sulfur, obtained if needles about 1 cm long are patiently crystallized from toluene ( Toluene is also flammable!). As is known, in nature, sulfur is often found in compounds with metals in the form of metal sulfides. Iron sulfide FeS, widely used in laboratories, is a bluish-black mass. We get it if we mix 20 g of pure iron powder with 11 g of sulfur powder (sulfur-colored) and heat it on a fireproof substrate. We will stir the mixture so that it heats evenly. After cooling, we obtain a solid residue.
Iron sulfide is used to produce hydrogen sulfide, which is used in chemical analysis to precipitate metals. Place a little (about the size of a pea) of the resulting iron sulfide in a test tube and add dilute hydrochloric acid. Substances interact with violent gas release:

FeS + 2HCl = H 2 S + FeCl 2

An unpleasant smell of rotten eggs emanates from the test tube - this disappears hydrogen sulfide. If you pass it through water, it will partially dissolve. A weak acid is formed, a solution of which is often called hydrogen sulfide water.
Extreme care must be taken when working with hydrogen sulfide, as the gas is almost as poisonous as hydrocyanic acid HCN. It causes paralysis of the respiratory tract and death if the concentration of hydrogen sulfide in the air is 1.2-2.8 mg/l. Therefore, experiments with hydrogen sulfide should be carried out only in the open air or under draft. Fortunately, the human olfactory organs sense hydrogen sulfide already at a concentration in the air of 0.0000001 mg/l. But with prolonged inhalation of hydrogen sulfide, paralysis of the olfactory nerve occurs, and here we can no longer rely on our sense of smell.
Chemically, hydrogen sulfide is detected using wet lead reagent paper. To obtain it, we moisten filter paper with a dilute solution of lead acetate or lead nitrate, dry it and cut it into strips 1 cm wide. ( Carefully! Lead salts are poisonous!)
Hydrogen sulfide reacts with lead ions, resulting in the formation of black lead sulfide:

Pb 2+ + S 2-- = PbS↓

We use other strips of prepared lead reagent paper for experiments with natural hydrogen sulfide - let's check presence of hydrogen sulfide in spoiled food products (meat, eggs) or we examine the air above the cesspool and in the barn.
We recommend obtaining hydrogen sulfide for experiments using the dry method, since in this case the gas flow can be easily adjusted and shut off at the right time. For this purpose, melt about 25 g of paraffin (candle residue) in a porcelain cup and mix 15 g of sulfur-colored melt with the melt. Then remove the burner and stir the mixture until it hardens. If we stop stirring early, the sulfur particles will be unevenly distributed in the hardening paraffin. Grind the solid mass and save it for further experiments.
When it is necessary to obtain hydrogen sulfide, we heat several pieces of a mixture of paraffin and sulfur in a test tube with a gas outlet tube to a temperature above 170 °C. As the temperature rises, the gas output increases, and if the burner is removed, it stops. During the reaction, paraffin hydrogen interacts with sulfur, resulting in the formation of hydrogen sulfide, and carbon remains in the test tube, for example: To examine the color of precipitated metal sulfides, let's pass hydrogen sulfide through solutions of various metal salts. Sulfides of manganese, zinc, cobalt, nickel and iron will precipitate if an alkaline environment is created in the solution (for example, by adding ammonium hydroxide). Sulfides of lead, copper, bismuth, cadmium, antimony and tin precipitate in the hydrochloric acid solution. Let's enter our observations into a table, which will be useful for further experiments. Having made a preliminary test for detonating gas, let’s ignite the hydrogen sulfide coming out of a glass tube drawn at the end. Hydrogen sulfide burns with a pale flame with a blue halo:

2H 2 S + 3O 2 = 2H 2 O + 2SO 2

As a result of combustion, sulfur(IV) oxide is produced - “sulfur dioxide”. It is easily identified by its pungent odor and the redness of wet blue litmus paper.
If there is insufficient access to oxygen, hydrogen sulfide is oxidized only to sulfur. Activated carbon catalytically accelerates this process. This method is often used for fine purification of industrial gases, the sulfur content of which should not exceed 25 g/m3:

2H 2 S + O 2 = 2H 2 O + 2S

It is not difficult to reproduce this process. The installation diagram is shown in the figure. The main thing is to pass air and hydrogen sulfide through the activated carbon in a ratio of 1:3. The coal will release yellow sulfur.
Activated carbon can be cleaned of sulfur by washing it in carbon disulfide. In technology, a solution of ammonium sulfide (NH 4) 2 S is most often used for this gap.

TWO METHODS FOR ONE PRODUCT

The sulfur burns with a pale blue flame. This produces a colorless gas with a pungent odor - sulfur oxide (IV) SO 2. It is poisonous and irritates the respiratory tract, so we should try not to inhale it. Sulfur dioxide (IV) - sulfur dioxide - is extremely soluble in water, resulting in the formation of sulfurous acid (sulfur dioxide hydrate):

H 2 O + SO 2 = SO 2 * H 2 O

It kills germs and has a whitening effect. In breweries and wineries, barrels are fumigated with sulfur. Sulfur dioxide is also used to bleach wicker baskets, wet wool, straw, cotton and silk. Blueberry stains, for example, are removed if you keep the moistened, contaminated area in the “vapor” of burning sulfur for a long time.
Let's check the bleaching effect of sulfurous acid. To do this, put various colored objects (flowers, wet pieces of fabric, damp litmus paper, etc.) into the cylinder, where pieces of sulfur were burning for some time, close the cylinder well with a glass plate and wait for a while.
Anyone who has ever studied atomic structure elements, knows that in the sulfur atom there are six so-called valence electrons in the outer orbit. Therefore, sulfur can be maximally hexavalent in compounds. This oxidation state corresponds to sulfur(VI) oxide with the formula SO 3. It is a sulfuric anhydride:

H 2 O + SO 3 = H 2 SO 4

When sulfur is burned under normal conditions, sulfur(IV) oxide is always produced. And if a certain amount of sulfur(VI) oxide is formed, then most often it immediately decomposes under the influence of heat into sulfur(IV) oxide and oxygen:

2SO3 = SO2 + O2

In the production of sulfuric acid, the main problem is the conversion of SO 2 to SO 3. For this purpose, two methods are currently used: chamber(or improved - tower) And contact. Fill a large vessel (500 ml round-bottomed flask) with sulfur oxide (IV) SO2, placing burning pieces of sulfur in it for a while or supplying gas from the apparatus where it is formed. Sulfur(IV) oxide can also be prepared relatively easily by dropping concentrated sulfuric acid into a concentrated solution of sodium sulfite Na 2 SO 3 . In this case, sulfuric acid, being stronger, will displace the weak acid from its salts.
When the flask is filled with gas, close it with a stopper with three holes. In one, as shown in the figure, we insert a glass tube bent at a right angle, connected to the side outlet of the test tube, in which nitric oxide (IV) is formed by the interaction of pieces of copper and nitric acid:

4HNO 3 + Cu = Cu(NO 3) 2 + 2H 2 O + 2NO 2

The acid concentration should be about 60% (wt). Attention! NO 2 is a strong poison! Into another hole we will insert a glass tube connected to the test tube, through which water vapor will later flow.
In the third hole we insert a short piece of tube with a Bunsen valve - a short piece of rubber hose with a slot. First, let's create a strong influx of nitric oxide into the flask.
But there is no reaction yet. The flask contains a mixture of brown NO 2 and colorless SO 2.
As soon as we pass the water vapor, a change in color will indicate that the reaction has begun. Under the influence of water vapor, nitrogen oxide(IV) oxidizes sulfur oxide(IV) to sulfur oxide(VI), which immediately, interacting with water vapor, turns into sulfuric acid:

2NO 2 + 2SO 2 = 2NO + 2SO 3

2NO + O 2 = 2NO 2

Colorless condensate will collect at the bottom of the flask, and excess gas and vapor will escape through the Bunsen valve. Let's pour the colorless liquid from the flask into a test tube, check the acidic reaction with litmus paper and detect the sulfate ions SO 4 2 - of the resulting sulfuric acid by adding a solution of barium chloride. A thick white precipitate of barium sulfate will indicate to us that the experiment was successful.
By this principle, but on a much larger scale, sulfuric acid is produced in technology. Previously, reaction chambers were lined with lead, as it is resistant to sulfuric acid vapor. In modern tower installations, ceramic-based reactors are used. But larger quantities of sulfuric acid are now produced using the contact method. Various raw materials are used in the production of sulfuric acid. Pure sulfur began to be used in the GDR only recently. In most cases, enterprises produce sulfur(IV) oxide by roasting sulfide ores. In a rotary tube kiln or multi-deck kiln, pyrite reacts with atmospheric oxygen according to the following equation:

4FeS 2 + 11O 2 = 2Fe 2 O 3 + 8SO 2

The resulting iron(III) oxide is removed from the furnace in the form of scale and further processed in iron production plants.
Crush several pieces of pyrite in a mortar and place them in a refractory glass tube, which we close with a stopper with a hole. Then use a burner to heat the tube strongly, while simultaneously passing air through it using a rubber bulb. In order for the volatile dust from the roasting gas to settle, we will take it into an empty glass vessel, and from it into a second refractory tube, which contains a catalyst heated to 400-500 °C.
In technology, vanadium(V) oxide V2O5 or sodium vanadate NaVO3 is most often used as a catalyst, and for this purpose we will use red iron(III) oxide Fe2O3. Apply finely ground iron oxide onto glass wool, which we distribute in a tube in a layer 5 cm long. Heat the tube with the catalyst until it reaches red heat. On the catalyst, sulfur(IV) oxide reacts with atmospheric oxygen; as a result, sulfur oxide (VI) is formed

2SO2 + O2 = 2SO3

Which we recognize by its ability to form fog in moist air. Collect SO 3 in an empty flask and, shaking vigorously, mix with a small amount of water. We will obtain sulfuric acid - we will prove its presence, as in the previous method.
You can also place the pyrite and catalyst, separated by glass wool, into one of the glass tubes. You can also work in a test tube with a side outlet. Let's put pyrite at the bottom of the test tube, a layer of glass wool on it, and then glass wool with a catalyst. We introduce air from above through a tube that should fit close to the catalyst. On the side branch we will attach a tube bent at an angle, which leads into the test tube.
If there is no pyrite, then in a test tube with a side outlet we will obtain sulfur(IV) oxide from sodium sulfite or hydrosulfite and sulfuric acid, and then pass the resulting gas over the catalyst along with a stream of air or oxygen. Chromium(III) oxide can also be used as a catalyst, which should be calcined in an iron crucible and finely crushed in a mortar. For the same purpose, you can soak a clay shard with a solution of iron(II) sulfate and then strongly calcinate it. In this case, a fine powder of iron(III) oxide is formed on the clay. If there are few metal sulfides (as, for example, in the German Democratic Republic), then the starting products for the production of sulfuric acid can be anhydrite CaSO 4 and gypsum CaSO 4 * 2H 2 O. The method for producing sulfur oxide (IV) from these products was developed by Müller and Kuehne 60 years ago.
Methods for producing sulfuric acid from anhydrite will continue to be important in the future, since sulfuric acid is the most common chemical product. Installations for producing sulfuric acid from gypsum, produced in the GDR, are known and valued on the world market.
Sulfates can be decomposed using high (up to 2000 °C) temperatures. Müller found that the decomposition temperature of calcium sulfate could be reduced to 1200 °C by adding finely ground coke. First, at 900 °C, coke reduces calcium sulfate to sulfide, which in turn, at a temperature of 1200 °C, reacts with undecomposed sulfate; this produces sulfur(IV) oxide and quicklime:

CaSO 4 + 3C = CaS + 2CO 2

CaS+ 3CaSO 4 = 4CaO + 4SO 2

It will be possible to decompose calcium sulfate in laboratory conditions only if appropriate high temperature. We will work with equipment similar to that which was used for firing pyrite, only we will take a porcelain or iron tube for combustion. We close the tube with plugs wrapped in asbestos fabric for thermal insulation. Insert a capillary into the hole in the first plug, and into the second - a simple glass tube, which we connect to a washing bottle half filled with water or a fuchsin solution.
Let's prepare the reaction mixture as follows. Crush and mortar 10 g of gypsum, 5 g of kaolin (sold in a pharmacy under the name "Bolus alba") and 1.5 g of active powdered carbon. Dry the mixture by heating it for some time at 200 °C in a porcelain cup.
After cooling (preferably in a desiccator), add the mixture to the middle of the combustion tube. At the same time, pay attention to ensure that it does not fill the entire cross-section of the tube. Then we heat the tube strongly using two burners (one from below, the second obliquely from above) and, when the tube is heated, we pass a not too strong air flow through the entire system. Within 10 minutes, due to the formation of “sulfurous acid”, the fuchsin solution in the washing bottle will become discolored. Turn off the water jet pump and stop heating.
We can also get a high temperature if we wrap a porcelain tube as tightly as possible with a 750-1000 W heating coil (see figure). We connect the ends of the spiral with thick copper wire, which we also wrap around the tube many times, and then insulate it with porcelain beads and connect it to the plug. ( Be careful when working with 220 V voltage!) Naturally, a glass torch or blowtorch can also be useful as a heating source.
The technique works with a mixture of anhydrite, coke, clay, sand and pyrite cinder Fe2O3. A worm conveyor feeds the mixture into a 70-metre rotating tube kiln where the pulverized coal is burned. The temperature at the end of the furnace, at the combustion site, is approximately 1400 °C. At this temperature, the quicklime formed during the reaction is fused with clay, sand and pyrite cinder, resulting in cement clinker. The cooled clinker is ground and mixed with a few percent of gypsum. The resulting high-quality Portland cement goes on sale. With careful implementation and control of the process, from 100 tons of anhydrite (plus clay, sand, coke and pyrite cinder) you can get about 72 tons of sulfuric acid and 62 tons of cement clinker.
Sulfuric acid can also be obtained from kieserite (magnesium sulfate MgSO 4 *H 2 O), which is supplied in significant quantities by the salt mines of the GDR.
For the experiment, we will use the same setup as for the decomposition of gypsum, but this time we will take a tube made of refractory glass. We obtain the reaction mixture by calcining 5 g of magnesium sulfate in a porcelain bowl, and 0.5 g of active carbon in an iron crucible with a lid, and then mixing them and grinding them in a mortar to a dusty state. Transfer the mixture to a porcelain boat and place it in the reaction tube.
The white mass that will be obtained at the end of the experiment in the porcelain boat consists of magnesium oxide. In technology, it is processed into Sorel cement, which is the basis for the production of xylolite. The production of derivative products such as cement clinker and xylolite, which are important for the construction industry, makes the production of sulfuric acid from local raw materials particularly economical. Processing intermediates and by-products into valuable raw materials or final products is an important principle of the chemical industry. Mix equal parts of magnesium oxide and sawdust with a solution of magnesium chloride and apply a layer of the resulting slurry about 1 cm thick to the substrate. After 24-48 hours the mass will harden like stone. It does not burn, it can be drilled, sawed and nailed. In the construction of houses, xylolite is used as a flooring material. Wood fiber, hardened without filling the gaps with Sorel cement (magnesium cement), pressed and glued into slabs, is used as a lightweight, heat- and sound-proof building material.

VALUABLE SILICATES

Now that we have looked at natural chlorides and sulfates as the main raw materials for chemical production, it is necessary to say a little about silicates.
Silicon is the second most abundant element (after oxygen) in the lithosphere of our planet (almost 28%). It is found mainly in the form of silicic acid salts of various metals, as well as in the form of pure oxide (quartz SiO 2). Silicate anions can have a simple formula, similar to sulfates; however, complex structures are most often found, for example, (SiO 3) n, (Si 2 O 5) n or (SiO 2) n. Yes, y albite feldspar the formula is NaAl, and the layered silicate kaolin corresponds to the composition Al 4 (OH) 8.
Unfortunately, chemical experiments with silicates are not easy to carry out, since the production or transformation of silicates most often occurs at temperatures above 1400 °C.
Silicates are often not crystalline, but glassy or sintered ceramic mass. In this case, groups of molecules can form rings or so-called network structures. These substances are not destroyed when dissolved. In practice, they can only be destroyed with hydrofluoric acid, which creates great difficulties in analytical chemistry silicates. On the other hand, silicate materials are of great importance as construction raw materials, and the production of cement, glass and ceramics is rapidly increasing in accordance with the ever-increasing demand for construction materials. Recently, new types of materials have been created, for example, foam concrete and foam glass. Commercially available liquid glass is a syrupy solution of sodium silicate. (Na 2 Si 2 O 3) n or potassium (K 2 Si 2 O 3) n. Mixed with various additives such as alumina, gypsum or sawdust, it can be used to make putties. It is widely used in the production of fire-resistant paint and fire-resistant coatings.
We will add hydrochloric acid drop by drop to a test tube with half-diluted liquid glass. We will notice the appearance of a thick white precipitate of silicic acid (H 2 SiO 3) n or its anhydride. As the sediment increases, the silicic acid particles form a structure in which all remaining water is bound. Finally, with some degree of dilution, a flexible, solid silicic acid gel is obtained.
In the following experiments we will consider the properties of silica gel with different water contents. In small plastic cups (for example, in the lids of medicine jars) filled with liquid glass with varying degrees of dilution, add hydrochloric acid drop by drop and stir the resulting mass. We invite the reader to choose the degree of dilution of the starting substance in the range from 1: 100 to undiluted liquid glass. After some time, more or less viscous compounds are formed, which then turn into elastic gelatinous or hard masses of silicic acid gel. Here we are talking about a fine colloidal dispersed distribution of silicic acid, which has completely incorporated the available water into its structure.
Fresh silicic acid gel, in which there are 300 H 2 O molecules per SiO 2 molecule, is very mobile. If there are 30-40 H 2 O molecules per SiO 2 molecule, then the gel is solid and can be cut with a knife. After drying with low heat, it will remain six molecules of H 2 O per molecule of SiO 2, and the gel can be ground to a fine state.
Let's grind this sample in a mortar or grind it in an old coffee grinder. Then dry the powder in a porcelain cup or crucible, heating it on a Bunsen burner. In this case, a silicon xerogel is formed (from the Greek xeros- dry). This more or less porous substance, having a very large specific surface area (up to 800 m 2 /g), has a strong adsorbing ability. Due to this property, dry gel is used to absorb water vapor from the atmosphere. It is used for drying closed volumes, for example inside packages of valuable machines and devices.
In laboratories, silica gel cartridges are placed in the casing of analytical balances; it is used to fill gas drying towers. Most often, the so-called blue gel is used - with the addition of anhydrous cobalt(II) chloride (See the section “Detecting water of crystallization”). When the ability to absorb water is lost, the blue gel turns pink. We can get the blue gel ourselves if we mix the xerogel with a small amount of finely ground and well-dried cobalt(II) chloride.
We will check the ability to absorb water by placing a little dried gel on a watch glass in humid air, for example in the kitchen or outdoors. We will begin to weigh this sample, first at short (10 minutes) and then at long intervals. If you plot a graphical dependence of mass increase on time on a sheet of graph paper, then the resulting curve will end with an area corresponding to the saturation value and indicating the maximum degree of water absorption. True, relative air humidity plays a certain role in this case. Concrete is now undoubtedly the most important building material. Highway pavements, slabs, pillars, beams, and structures of modern residential buildings and industrial buildings are mostly made of concrete. Concrete mixtures differ in density, strength and thermal insulation properties. What they have in common is that they are all made of cement and after some time after mixing with water they harden, absorbing moisture. This is the most important difference between concrete and classic lime mortar, the hardening of which occurs under the influence of carbonic acid with the release of water.
High-quality Portland cement is produced by burning a mixture of limestone, clay or marl and ferrous waste, such as blast furnace slag. This process takes place at a temperature of about 1450 °C in a huge (over 100 m long) rotating tube furnace. The important components of Portland cement are di- and tricalcium silicate, tricalcium aluminate and tetracalcium aluminoferrite. When hardened, reaction with water produces silicate hydrates, which, similar to the silicate gel described in the previous section, envelop the filler and contribute to the formation of a rock-hard substance. After we have already carried out a number of experiments with gels described in the previous section, which have different strength properties depending on the method of their preparation, especially on the addition of water, we can carry out several simple experiments on concrete hardening.
First we will make a simple mold to obtain cement bars. To do this, we divide a flat cigar box using slats so that we get identical shapes 1 - 2 cm in cross section, and their length will be equal to the length of the box.
We will place the following mixtures in separate zones: 1 part Portland cement and 1, 3, 5 or 8 parts clean sand; 1 part Portland cement, 2 parts sand and 2 parts brick chips (grind the brick); 1 part Portland cement, 3 parts sand and 2 pieces of steel wire (old knitting needles), which should be placed as parallel as possible on both sides of the form and try to insert them into the concrete.
Before filling the molds, add a little water to the mixture to make a moist but crumbly mass (like wet soil). Fill the molds with these mixtures and compact them thoroughly with a wooden stick. Over the next two days we will wet the cement with water from a spray bottle or a watering can with small holes. Two days later, after knocking on the mold, we will pull out the frozen samples from it, place their ends on the edges of two chairs, and for greater accuracy, place triangular files or other metal objects with edges under the bars at equal distances. We will hang a load on a strong wire from the middle of the block, increasing it until a break appears. In another experiment, we will check the compressive strength of the samples by hitting them with a hammer or a thin chisel.
Finally, when obtaining samples, we can vary the addition of water and the degree of moisture during curing. When tested, it will be found that concrete obtained from an initial mixture of high humidity or not moistened during curing is significantly inferior in strength. Heat- and sound-insulating gas or foam concrete is produced by adding aluminum or calcium carbide powder to a viscous concrete mass. If a surfactant, such as a detergent, is added at the same time, the resulting gas bubbles will form a particularly fine foam.
Along with foam concrete, the use of foam glass and building parts made of light metals and plastics opens up new possibilities, which have already been successfully implemented at pilot construction sites.

Sulfur and its compounds are among the most important classes of pesticides.
Sulfur is a yellow solid. There are crystalline and amorphous varieties. Sulfur does not dissolve in water, it dissolves well in carbon disulfide, aniline, phenol, benzene, gasoline, and poorly in alcohol and chloroform. At elevated temperatures it combines with oxygen, metals and many non-metals. Available in the form of 80-90% wetting powder, 70-75% colloidal sulfur, and ground sulfur.
Ground sulfur does not dissolve in water and is poorly wetted by it.
Colloidal sulfur It is well wetted with water and, when shaken or stirred, creates persistent cloudy suspensions. Evaporates weakly and slowly.
Produced and transported in metal and wooden barrels; and also in paper bags treated with a waterproof substance. When stored in loose containers, colloidal sulfur dries out, turning into lumps, and then mixes very poorly with water.
In livestock farming, colloidal sulfur is used to combat psoroptosis in cattle by spraying animals with a 3% aqueous suspension with a consumption of 3-4 liters per animal, twice, with an interval of 7-10 days.
Sulfur is low toxic. Acute poisoning when working with it is excluded. However, prolonged inhalation may cause respiratory problems.
Sulfur cuttings- molten sulfur turned into a cylindrical shape. Lit. When 1.4 g is burned, 1 liter of sulfur dioxide is obtained. The antiparasitic effect of sulfur is due to the formation of sulfur dioxide, hydrogen sulfide, oxygen, in the presence of moisture, alkalis and organic compounds. In concentrations of 5-8%, sulfur has a softening, keratoplastic, anti-inflammatory effect and a weak anti-scabies, and in high concentrations, due to the formation of sulfuric and sulfurous acids, irritating, drying and keratolytic effects develop. Sulfur cuttings are used to treat animals suffering from scabies, trichophytosis, microsporia, furunculosis, seborrhea, eczema, dermatitis in the form of 10-30% purified sulfur ointment or 5-10 and 20% precipitated sulfur ointment, as well as in the form of liniments and dusts.
To treat scabies, use sulfur ointment (sulfur 6 parts, green soap - 8, potassium carbonate - 1 and petroleum jelly - 10 parts).
Purified sulfur- sulfur, free from all impurities, is produced in powder in carefully closed containers. Purified sulfur has an antiparasitic and antidote effect against many poisonings. It is used in all cases as cutting sulfur.
Sulfur precipitated- purified from many impurities. Lit. When burned, sulfur dioxide is formed, which has antiparasitic and insecticidal effects. Pharmacodynamics and mechanism of action are the same as those of cutting sulfur. Available in powder form, in well-closed jars.
Sodium sulfate- a sulfur-containing substance with an antiparasitic effect. The mechanism of action is the formation of sulfur dioxide and sulfur during the interaction of sodium thiosulfate molecules with a molecule of acids or acid salts, as a result of which the redox processes in the parasites sharply change.
It is produced in powder form, which must be stored in a well-closed container.
Demos- an acaricidal drug, which includes sulfur and auxiliary components. This is a light brown liniment with a weak specific odor. The drug is produced in glass or plastic bottles with a capacity of 10, 15 and 20 ml. Store demos at a temperature of 0-25°C in a place protected from light. Shelf life - 2 years from the date of manufacture.
Demos is active against sarcoptoid mites - the causative agents of psoroptic mange in rabbits, otodectic mange in carnivores, notoedrosis in cats, as well as against the causative agent of demodicosis in dogs.
The drug has low toxicity for warm-blooded animals, it does not have an irritating or sensitizing effect.
When treating animals with ear scabies, first thoroughly clean the auricles from scabs with a swab soaked in camphor alcohol, then inject 1.5-3.0 ml of demos into the auricle using a pipette and lightly massage the auricle at the base. If other parts of the body are affected, the drug is rubbed into the affected areas using a cotton gauze swab at the rate of 0.1-0.3 cm of adjacent healthy skin.
Animals with large areas of skin lesions are treated in 2 doses, with an interval of 1 day, applying the drug first to one half and then to the other half of the affected surface of the body.
Plison(diphenyl disulfide), C12H10S2. Obtained by mixing coal oil 22-42%, diphenyl sulfide 6-10%, emulsifier OP-7 (rosin) or OP-10 (neonol) - 15-20% and water up to 100%. Diphenyl disulfide is produced as a by-product in the production of coal-tar phenols.
Plizon is a homogeneous, dark-colored oily liquid. The aqueous emulsion of this drug is stable for 4 hours at room temperature. The drug is low-toxic; when applied cutaneously, the LD50 is 12,500 mg/kg. 0.5% plison emulsion (therapeutic concentration) is well tolerated by sheep and is not accompanied by changes in the morphological picture of the blood. Plizone 2% causes a decrease in the activity of cholinesterase and alkaline phosphatase on the first day after purchase, without the manifestation of clinical signs of toxicosis.
Plizon, according to research by O.D. Yanyshevsky et al., is excreted from the internal organs and tissues of sheep treated with a 0.5% emulsion after 40 days, and from fat after 65. In animals treated with a 0.25% plison emulsion, diphenyl disulfide was absent in the internal organs and tissues after 20 days. It persists on sheep wool for up to 5 months in an amount of 15.1 mg/kg. It is not excreted in the milk of suckling ewes.
Lepran- a sulfur-containing product from the processing of benzothiophene coal tar. The liquid is dark brown in color with the smell of coal oil. When mixed with water, lepran forms a stable light brown emulsion. The drug consists of benzothiophene - 10-14%, coal oil 57-64, emulsifier 25-30 and water up to 100%. Lepran is low toxic, its LD50 when buying sheep is 14250 mg/kg. The cumulation coefficient is more than 5.28, which indicates weak cumulative properties, and does not have allergenic or irritating properties to the skin and mucous membranes. When treating sheep (one-time purchase) with 2% leprane emulsion (0.22% DDV), according to research by B.A. Timofeev, the drug does not have mutagenic properties, does not change hematological parameters of phosphatase, veterinary and sanitary indicators of the quality of sheep meat. 50 days after treatment, benzothiophene is not detected in the organs and tissues of sheep, the meat is suitable for release and sale for food purposes. Benzothiophene is not excreted in milk; the drug can be used to treat pregnant and lactating sheep.
In cases of poisoning of animals with sulfur-containing drugs, activated carbon, burnt magnesia, and a laxative are used internally.

Sulfur is widespread on Earth. Numerous deposits of sulfur in a free state are located in Mexico, Poland, the island of Sicily, the USA, the USSR and Japan. Sulfur deposits in Poland are the second in the world, they are estimated at 110 million tons and are almost as good as those in Mexico. The deposits in Poland were fully assessed only in 1951, development began in 1957. In 1970, 2.6 million tons were already produced, and then annual production reached 5 million tons.

Sulfur is a component of various minerals: it can be found in seawater in the form of sulfites. Plant and animal organisms contain sulfur bound in protein; in coal, which is formed from plants, sulfur is found bound in organic compounds or in the form of compounds with iron (sulfur pyrite FeS2). Brown coal can contain up to 6% sulfur. The coal processing industry of the GDR receives 100,000 tons of sulfur annually when purifying coke oven, water and generator gas.

Dissolving sulfur

Sulfur vapor reacts with hot coal to form carbon disulfide CS2 (carbon disulfide), a flammable liquid with an unpleasant odor. It is indispensable in the production of artificial silk and staples. Sulfur, which is known to be insoluble in water and dissolves in small quantities in benzene, alcohol or ether, is perfectly soluble in carbon disulfide.

If you slowly evaporate a solution of a small amount of sulfur in carbon disulfide on a watch glass, you will get large crystals of the so-called rhombic or -sulfur. But let’s not forget about the flammability and toxicity of carbon disulfide, so let’s turn off all the burners and place the watch glass under the draft or in front of the window.

Sulfur (Latin – Sulfur, S) is a macroelement. There is quite a lot of it in our body. All of it is part of many organic compounds. Forms the structure of proteins, activates enzymes, improves immunity. This has a positive effect on the condition of all tissues and organ systems.

History of discovery

This non-metal has been known to mankind since ancient times. It was used for domestic, medical, and military purposes. Sulfur compounds were used to bleach fabrics, treat skin diseases, and in the production of cosmetics.

It was part of Greek fire, an incendiary substance intended to destroy the enemy. It was used to produce black smoky powder, which, in addition to military purposes, was used in the production of fireworks.

There was also some mysticism. Alchemists used sulfur to search for the philosopher's stone. Like any flammable substance, it was considered a gift from God. Its combustion in the atmosphere was accompanied by the formation of sulfur dioxide, SO 2. This suffocating gas had an unpleasant odor. Another gas was equally unpleasant - hydrogen sulfide, H 2 S, which gave off the aroma of rotten eggs. According to the ideas of that time, such unpleasant odors could only come from the devil himself.

In the old days, sulfur was smelted from metal ores that contained it. When the ore was heated, a substance was released and solidified in the form of light yellow crystals. The origin of the name is not exactly known. It is believed that Lat. Sulfur takes its name from the Indo-European word for flammable substance. The same applies to the Slavic “sulphur”. Although some consider it to be a derivative of the Old Slavonic “syrah”, light yellow.

Physical and chemical properties

In the periodic table, S is listed at No. 16, and is located in group 16, in the 3rd period. Its atomic mass is 32. There are 6 electrons rotating in the outer orbit of the sulfur atom. There are 2 electrons missing before the orbit is filled.

When interacting with some substances, it adds these 2 electrons, while being divalent. But the radius of the sulfur atom is relatively large. Therefore, it can not only gain, but also donate electrons, and its valency ranges from 2 to 6.

In its normal state, S is hard but brittle light yellow crystals with a melting point of 112.5 0 C and a density of about 2 g/cm 3 . The molecule consists of 8 atoms, and its configuration resembles a crown. Depending on the heating regime, it acquires several allotropic modifications - varieties that differ in physical properties and molecular structure.

Sulfur is insoluble in water, but dissolves well in a number of organic solvents, incl. in alcohol and gasoline. Conducts heat and electricity very poorly. In nature it can be found both in pure form (native sulfur) and in the form of compounds, sulfides and sulfates. Sulfur-containing compounds are part of rocks and are dissolved in the water of seas and lakes. The earth's crust contains 4.3 X 10 -3% sulfur. According to this indicator, among other elements of the periodic table, it ranks 15th. However, in the deeper layers of the earth, in the mantle, there is much more of it.

Physiological action

It would seem, what could be the benefit for our health from a flammable substance, many of whose compounds have an unpleasant odor and have a suffocating effect. But sulfur is a macronutrient, and its content in the body of an adult is about 140 g. Only two other macroelements – calcium and phosphorus – are higher.

This substance in our body is not ballast at all. After all, Nature does nothing in vain, every step is thought out, and every element plays its role. But what is the role of sulfur? None. Then what positive effects does it have? All.

This paradox is only apparent. Yes, by itself, taken in its pure form, sulfur may not be beneficial. But in connections it manifests itself in all its glory. It is enough to mention sulfhydryl groups. These groups (thiol groups, SH groups) are formed by residues of the amino acid cystine.

This is a proteinogenic amino acid, i.e., one that is part of proteins. Sulfhydryl groups, as the name and designation suggest, consist of hydrogen and sulfur atoms. Two adjacent SH groups form the so-called. disulfide bridges or disulfide groups (S-S groups), consisting of two sulfur atoms.

These disulfide groups form the structure of proteins. Each protein is essentially a polypeptide - a combination of a large number of peptides formed by amino acid residues. The sequence of peptides in a chain is the primary structure. The chain is spirally twisted - this is the secondary structure. A spirally twisted chain can take various forms (thread, ball) - this is a tertiary structure. Finally, the molecules of a number of proteins can be formed not by one, but by several polypeptide chains, which are connected to each other in strictly defined places. This is the quaternary structure of a protein.

Tertiary and quaternary structures determine the spatial configuration or conformation of a protein molecule. The properties of a protein depend on its conformation. Under the influence of temperature, chemical compounds, and other factors, the tertiary and quaternary structures are disrupted. This process called protein denaturation. Denatured protein loses its properties.

Sulfur in the composition of sulfhydryl groups and disulfide bridges forms a kind of rigid frame that helps the protein molecule maintain conformation. Thanks to this, the protein retains its properties.

It is known that enzymes, these catalysts of biochemical reactions, are proteins. Therefore, sulfur helps enzymes maintain their activity. And indeed it is. Under the influence of damaging factors, disulfide bridges are destroyed and the enzyme is inactivated.

Enzymes are not entirely proteins. They contain a non-protein part, a coenzyme. Vitamins, vitamin-like substances, other organic compounds, and even metals (metal enzymes) can act as coenzymes. Sulfhydryl groups provide the connection between the apoenzyme (the white component of the enzyme) and the coenzyme.

The value of sulfur is not limited to the formation of sulfhydryl groups and disulfide bridges. It is part of many other biologically active substances. In addition to the aforementioned cysteine ​​and its derivative cystine, sulfur-containing amino acids include tauirne and methionine. Taurine – component taurocholic acid, one of the bile components. A methionine derivative, S-Methylmethionine, better known as vit. U, has an anti-ulcerogenic effect - prevents the development of gastric and duodenal ulcers.

As part of these compounds, S regulates the function of organ systems and affects vital processes:

The cardiovascular system

• normalizes blood pressure (BP) and prevents the development of hypertension
• strengthens vascular walls
• prevents the development of vascular atherosclerosis
• increases the strength of heart contractions.

Blood

• stimulates red blood cell synthesis
• as part of hemoglobin, it transports oxygen and carbon dioxide
• normalizes blood clotting
• prevents pathological thrombus formation.

Respiratory system

• prevents bronchospasm
• improves gas exchange in the pulmonary alveoli.

Digestive system

• participates in the neutralization of toxins by the liver and their subsequent excretion with bile through the intestines
• strengthens the mucous membranes of the gastrointestinal tract (gastrointestinal tract)
• prevents the development of inflammatory processes and ulceration
• emulsifies fats and improves their absorption in the small intestine
• facilitates the absorption of other nutrients (nutrients) in the gastrointestinal tract
• improves gastrointestinal motility
• has a positive effect on the state of the physiological intestinal microflora that synthesizes B vitamins
• improves gastrointestinal motility, promotes the formation of feces.

Nervous system

• improves cerebral blood flow, prevents the formation of blood clots in cerebral vessels
• has a positive effect on the emotional-volitional sphere
• improves thinking and memory
• normalizes sleep
• slows down age-related degenerative changes leading to Alzheimer's disease
• has an anticonvulsant effect.

Musculoskeletal system

• increases muscle strength and endurance
• strengthens the ligamentous apparatus, bones, articular ligaments
• reduces the intensity of joint and muscle pain
• reduces the risk of bone fractures, and in case of existing fractures, accelerates the healing of bone fragments
• prevents the development of arthritis.

Skin and appendages

• increases skin strength and elasticity
• acts in a similar way on hair, preventing hair loss
• Composed of melanin, it protects the skin from the damaging effects of sun rays
• accelerates the healing of skin wounds
• slows down the natural aging process with the appearance of wrinkles, stretch marks, and age spots.

Genitourinary system

• along with other factors, regulates the processes of filtration and reabsorption (reabsorption) in the renal tubules with the formation of urine
• promotes the removal of toxic substances and metabolic products in the urine
• prevents the appearance of tissue edema
• ensures spermatogenesis in men, ovulation in women, normalizes the menstrual cycle
• during childbirth, the composition of oxytocin increases the contractile activity of the uterus, prevents the development of bleeding during childbirth and in the postpartum period
• forms libido in both sexes.

Metabolism

• as part of enzymes and hormones, it participates in all types of metabolism: protein, carbohydrate, fat (lipid), and water-salt
• regulates anabolism and catabolism (synthesis and breakdown) of proteins
• prevents obesity and diabetes
• normalizes acid-base balance
• prevents excessive acidification (acidosis) and alkalization (alkalosis) in tissues during various pathological processes.

Other effects

Sulfur is included in the composition of immunoglobulin antibodies, which provide specific humoral immunity against pathogenic bacteria, viruses, and fungi. In addition, it is part of lysozyme. This enzyme in the human body also destroys pathogenic bacteria. S is included in many antioxidant systems. It inhibits free radical oxidation, during which cell membranes are damaged.

Thanks to this macroelement, damaged cell membranes are restored. It reduces the severity of inflammatory reactions with pain and fever. It inhibits all 3 phases of inflammation:

1. alteration (damage)
2. exudation (appearance of liquid effusion)
3. proliferation (pathological cell growth).

S increases the body's resistance to ionizing radiation and reduces the risk of malignant tumors. In general, sulfur combines all the positive features of the enzymes, amino acids, and vitamins that it contains.

Daily requirement

The adult body needs 0.5-1.2 g of sulfur for normal functioning. Although some believe that the need for this macronutrient is much higher. They give figures of 3-4 g, and even 4-5 g. Probably, a lot depends on the state of health and lifestyle. Intense sports, physical activity, recovery from serious illnesses and fractures, pregnancy - all this increases the need for S.

Causes and signs of deficiency

There are no specific reasons that lead only to sulfur deficiency. The deficiency of this macronutrient may be associated with a small amount of sulfur-containing amino acids. Some of them, in particular methionine, are essential for us and enter the body only as part of food.

But a lack of methionine by itself is unlikely to lead to a decrease in sulfur levels in the body. After all, this macronutrient is present in many animal and plant foods, and its deficiency can only be caused by complete starvation or severe restrictive diets.

Other reasons include:

• serious illnesses
• increased physical activity
• gastrointestinal diseases, dysbacteriosis
• pregnancy
• congenital deficiency of certain enzymes responsible for the absorption of sulfur-containing products.

Signs of deficiency are as nonspecific as its causes. Patients may complain of general weakness and low performance. This is also facilitated by a decrease in muscle tone and strength. On the part of the musculoskeletal system, osteoporosis, frequent arthrosis and arthritis are noted.

The risk of cardiovascular diseases (hypertension, atherosclerosis), obesity, diabetes mellitus, and cancer increases. Due to low immunity, susceptibility to infections appears. As a result of digestive disorders, the absorption of other nutrients deteriorates. Children are stunted in growth and development.

Products containing sulfur

Most sulfur is found in foods rich in protein, where it is included in amino acids. Therefore, the main suppliers of this macronutrient for us are animal products - meat and meat by-products, primarily liver. But there is also a lot of it in vegetable proteins contained in legumes, grains, and nuts.

Product	Content, mg/100 g
Rabbit meat	1050
Fish (pink salmon, flounder, sardine)	1050
Chicken, chicken eggs	1050
Quail eggs	200
Turkey, turkey liver	248
Beef	230
Beef liver	239
Peanut	350
Hard cheeses	260
Soybeans	245
Mutton	230
Pork	230
Pork liver	187
Dried apricots	170
Dried peach	240
Barley	120
Coffee	110
Cocoa	200
Tea	215

Sulfur is also present in mineral waters in the form of sulfates and hydrogen sulfide. True, sulfate waters are taken for strictly defined purposes for the treatment of gastrointestinal disorders, where they have a choleretic and laxative effect. As for hydrogen sulfide waters, they are not intended for ingestion at all. They are used externally as baths.

Synthetic analogues

For medical purposes, purified, unrefined, and colloidal sulfur is used. Purified sulfur (Sulfur depuratum) or Sulfur color (Flos sulfuris) is a water-insoluble lemon-yellow powder. Purified has a complex effect:

Purified sulfur preparations can be used both internally, in powder form, and externally, in the form of powders and ointments. Purified S for oral use is indicated for gastrointestinal disorders accompanied by constipation, as well as for frequent sore throats, bronchitis, and other colds.

An interesting fact: once upon a time, back in Soviet times, there was an injectable form of purified sulfur - Sulfozin. It has been used as pyrogenic therapy.

Intramuscular injections of Sulfozin were accompanied by a sharp rise in temperature. According to the plan, this should have been accompanied by an antimicrobial effect and acceleration of metabolic processes.

Therefore, Sulfozin was used in the treatment of certain types of infections, in particular syphilis, as well as for organic disorders of the central nervous system. But the drug gained its loudest and worst fame after its use in psychiatry. Injections of Sulfozin (in slang - sulfa) are very painful.

Therefore, they were resorted to to eliminate psychomotor agitation in the mentally ill, as well as to “treat” dissidents. Currently, Sulfozin therapy is recognized as ineffective and barbaric, and the drug is a thing of the past.

Colloidal sulfur (Sulfur colloidale) is also used in dermatological practice. Being water soluble, it is more effective than purified and precipitated.

In the treatment of skin diseases, as well as some types of chemical burns, another sulfur-containing drug, Sodium thiosulfate, has proven itself well. But the indications for the use of Sodium thiosulfate are not limited only to the skin.

It is taken orally and administered intravenously as an antidote (antidote) for poisoning with heavy metal salts. Sodium thiosulfate is prescribed for allergies and certain diseases of the musculoskeletal system. Its effectiveness in the treatment of certain forms of female infertility has been proven.

Hydrogen sulfide, being toxic, in therapeutic concentrations also has a positive effect on the body. It is used in the form of baths. Gas dissolved in water penetrates the skin and has a healing effect.

Hydrogen sulfide baths are indicated for diseases of the skin, gastrointestinal tract, musculoskeletal system, male and female reproductive system. They are taken as part of the complex treatment of hypertension and diabetes.

In addition, sulfur is included in many other drugs - dietary supplements, homeopathic remedies, cosmetics.

Metabolism

A significant part of S enters the body as part of sulfur-containing amino acids. A certain amount may be presented in inorganic form, in the form of salts of sulfuric and sulfurous acids, sulfates and sulfites.

Organic sulfur is absorbed much better in the small intestine, while a significant part of inorganic compounds, without being absorbed, is excreted through the intestine.

It is noteworthy that some part of S is used by the intestinal microflora for its own needs. This produces hydrogen sulfide gas, which has an unpleasant smell of rotten eggs. Hydrogen sulfide, along with other components, gives the stench of intestinal gases.

Hydrogen sulfide can also form in the stomach during diseases accompanied by slower evacuation and stagnation of food. In this case, patients complain of characteristic belching of rotten eggs. In small concentrations, this gas has a positive effect. When the intestines are irritated by hydrogen sulfide, peristalsis is triggered reflexively.

Sulfur-containing compounds can enter the body through the skin and through the lungs. A significant part of the macroelement is concentrated in the tissues where metabolic processes occur most intensively. These are skeletal muscles, myocardium, liver, bones, and brain. In the blood, sulfur is found in the hemoglobin of red blood cells and in the albumin of plasma. Although some of it is dissolved directly in the plasma.

Here, as in other biological fluids of the body, it is mainly present in the form of sulfate anions, negatively charged SO 4 ions. In other tissues it is found in organic and inorganic forms - in the form of sulfites, sulfates, thioethers, thiols, thiocyanates, thiourea.

Quite a lot of S is concentrated in the skin, mainly in collagen and melanin. Sulfur is excreted mainly in urine in pure form or in the form of sulfates.

Interaction with other substances

Lead, molybdenum, barium, selenium, arsenic impair the absorption of sulfur. Fluorine and iron, on the contrary, have a positive effect on this process.

Signs of excess

Even with excessive consumption of sulfur-containing foods, it is impossible to achieve excess sulfur in the body. And S itself in its pure form is not toxic, which cannot be said about sulfur-containing compounds. Some of them, incl. Hydrogen sulfide and sulfur dioxide are present in gaseous form in industrial emissions into the atmosphere.

Hydrogen sulfide can be released as part of volcanic gases, or formed during the decay of protein substances. Inhalation of these substances leads to dire consequences. Thus, hydrogen sulfide blocks enzymes that carry out tissue respiration. In this respect it acts like other poisons, cyanide.

And sulfur dioxide, reacting with atmospheric moisture, forms sulfuric acid, which, when inhaled, causes destruction of lung tissue. Inhalation of sulfur-containing gases in high concentrations quickly leads to suffocation, loss of consciousness, convulsions, and death.

But even chronic intoxication with these substances in small quantities does not bode well. The skin and mucous membranes of the respiratory tract, eyes, oral cavity, and gastrointestinal tract are affected.

This is manifested by chronic bronchitis and emphysema. On the part of the eyes, there is a decrease in visual acuity and chronic conjunctivitis. Eczema, dermatitis with redness and rashes form on the skin. Patients complain of general weakness and decreased thinking abilities.

Damage to the gastrointestinal tract and liver, manifested by nausea, loss of appetite, and unstable stool. Such patients are at high risk of malignant oncology.

To reduce the toxicity of sulfur-containing products, it is recommended to Eat large quantities of eggs, hard cheeses, poultry, fatty pork, and beef.

However, when consuming food products, another danger lurks. The fact is that sulfur dioxide as a preservative is present in many confectionery products, smoked products, dried fruits, alcoholic and non-alcoholic drinks, and fruit juices. And even “fresh” vegetables and fruits stored in warehouses for a long time contain this preservative. It is designated as E220. This is nothing more than sulfur dioxide.

True, manufacturers and distributors of food products claim that the amount of E220 in products is negligible, and therefore it is not at all dangerous. And to harm your health, you need to eat a huge amount of such food.

But the diet modern man, living in the city, almost entirely consists of such products. Therefore, assurances of the safety of sulfur-containing preservatives are highly questionable.