Sulfuric acid finds the widest application in the national economy and is the main product of the main chemical industry. In this regard, there is a continuous increase in the production of sulfuric acid. Thus, if in 1900 the world production of sulfuric acid amounted to 4.2 million tons, then in 1937 18.8 million tons were produced, and in 1960 - more than 47 million tons.
Currently Soviet Union It ranks second in the world in the production of sulfuric acid. In 1960, 5.4 million grams of sulfuric acid were produced in the USSR. In 1965, the production of sulfuric acid will be doubled compared to 1958.
The areas of application of sulfuric acid are due to its properties and low cost. Sulfuric acid is a strong, non-volatile and durable acid, which at moderate temperatures has very weak oxidizing and strong water-removing properties.

The main consumer of sulfuric acid is production mineral fertilizers- superphosphate and ammonium sulfate. For example, to produce just one ton of superphosphate (from fluorapatite), which does not contain hygroscopic water, 600 kg of 65% sulfuric acid is consumed. The production of mineral fertilizers consumes about half of all acid produced.
A significant amount of sulfuric acid is consumed during processing liquid fuel— for purification of kerosene, paraffin, lubricating oils from sulfur and unsaturated compounds, during the processing of coal tar. It is also used in the purification of various mineral oils and fats.
Sulfuric acid is widely used in various organic syntheses, for example for sulfonation organic compounds— in the production of sulfonic acids, various dyes, saccharin. For this purpose, both concentrated acid and fuming acid, as well as chlorosulfonic acid, are used. Sulfuric acid is used as a water-removing agent in nitration reactions - in the production of nitrobenzene, nitrocellulose, nitroglycerin, etc.
Being a non-volatile acid, sulfuric acid is capable of displacing volatile acids from their salts, which is used in the production of hydrogen fluoride, hydrogen chloride, and perchloric acid.
Sulfuric acid is often used in the processing (decomposition) of certain ores and concentrates, such as titanium, zirconium, vanadium and sometimes niobium, lithium and some other metals. Since concentrated sulfuric acid boils at a fairly high temperature and has virtually no effect on cast iron and steel, this decomposition can be carried out quite completely using cheap equipment made from these materials.
Dilute hot sulfuric acid dissolves metal oxides well, and it is used for the so-called etching of metals - cleaning them< особенно железа, от окислов.
Sulfuric acid is a good drying agent and for this purpose is widely used in laboratories and industry. The residual moisture when using 95% sulfuric acid is equal to 0.003 mg of water vapor per 1 liter of dried gas.

Acids are chemical compounds consisting of hydrogen atoms and acidic residues, for example, SO4, SO3, PO4, etc. They are inorganic and organic. The first include hydrochloric, phosphoric, sulfide, nitric, and sulfuric acid. The second ones include acetic acid, palmitic acid, formic acid, stearic acid, etc.

What is sulfuric acid

This acid consists of two hydrogen atoms and the acidic residue SO4. It has the formula H2SO4.

Sulfuric acid or, as it is also called, sulfate acid, refers to inorganic oxygen-containing dibasic acids. This substance is considered one of the most aggressive and chemically active. In most chemical reactions it acts as an oxidizing agent. This acid can be used in concentrated or dilute form, in these two cases it has slightly different Chemical properties.

Physical properties

Sulfuric acid in normal conditions has a liquid state, its boiling point is approximately 279.6 degrees Celsius, the freezing point when it turns into solid crystals is about -10 degrees for one hundred percent and about -20 for 95 percent.

Pure 100% sulfate acid is an oily liquid substance odorless and colorless, which has almost twice the density of water - 1840 kg/m3.

Chemical properties of sulfate acid

Sulfuric acid reacts with metals, their oxides, hydroxides and salts. Diluted with water in different proportions, it can behave differently, so let’s take a closer look at the properties of concentrated and weak solutions of sulfuric acid separately.

Concentrated sulfuric acid solution

A solution containing at least 90 percent sulfate acid is considered concentrated. Such a solution of sulfuric acid is capable of reacting even with low-active metals, as well as non-metals, hydroxides, oxides, and salts. The properties of such a solution of sulfate acid are similar to those of concentrated nitrate acid.

Interaction with metals

During the chemical reaction of a concentrated solution of sulfate acid with metals located to the right of hydrogen in the electrochemical voltage series of metals (that is, with not the most active ones), the following substances are formed: sulfate of the metal with which the interaction occurs, water and sulfur dioxide. Metals, as a result of interaction with which the listed substances are formed, include copper (cuprum), mercury, bismuth, silver (argentum), platinum and gold (aurum).

Interaction with inactive metals

With metals that are to the left of hydrogen in the voltage series, concentrated sulfuric acid behaves slightly differently. As a result of this chemical reaction, the following substances are formed: sulfate of a certain metal, hydrogen sulfide or pure sulfur and water. The metals with which a similar reaction occurs also include iron (ferum), magnesium, manganese, beryllium, lithium, barium, calcium and all others that are in the voltage series to the left of hydrogen, except aluminum, chromium, nickel and titanium - with them concentrated sulfate acid does not interact.

Interaction with non-metals

This substance is a strong oxidizing agent, so it is capable of participating in redox chemical reactions with non-metals, such as, for example, carbon (carbon) and sulfur. As a result of such reactions, water is necessarily released. When this substance is added to carbon, carbon dioxide and sulfur dioxide are also released. And if you add acid to sulfur, you get only sulfur dioxide and water. In such a chemical reaction, sulfate acid plays the role of an oxidizing agent.

Interaction with organic substances

Among the reactions of sulfuric acid with organic substances, charring can be distinguished. This process occurs when this substance collides with paper, sugar, fibers, wood, etc. In this case, carbon is released in any case. The carbon formed during the reaction can partially react with sulfuric acid if it is in excess. The photo shows the reaction of sugar with a solution of sulfate acid of medium concentration.

Reactions with salts

Also, a concentrated solution of H2SO4 reacts with dry salts. In this case, a standard exchange reaction occurs, in which the metal sulfate that was present in the salt structure and the acid with the residue that was in the salt are formed. However, concentrated sulfuric acid does not react with salt solutions.

Interaction with other substances

Also, this substance can react with metal oxides and their hydroxides, in these cases exchange reactions occur, in the first, metal sulfate and water are released, in the second - the same.

Chemical properties of a weak solution of sulfate acid

Dilute sulfuric acid reacts with many substances and has the same properties as all acids. It, unlike concentrated metal, interacts only with active metals, that is, those that are to the left of hydrogen in the voltage series. In this case, the same substitution reaction occurs as in the case of any acid. This releases hydrogen. Also, such an acid solution interacts with salt solutions, resulting in an exchange reaction, already discussed above, with oxides - the same as a concentrated one, and with hydroxides - also the same. In addition to ordinary sulfates, there are also hydrosulfates, which are the product of the interaction of hydroxide and sulfuric acid.

How to tell if a solution contains sulfuric acid or sulfates

To determine whether these substances are present in a solution, a special qualitative reaction to sulfate ions is used, which makes it possible to find out. It consists of adding barium or its compounds to the solution. This may result in precipitation white(barium sulfate), which indicates the presence of sulfates or sulfuric acid.

How is sulfuric acid produced?

The most common method of industrial production of this substance is its extraction from iron pyrite. This process occurs in three stages, at each of which a certain chemical reaction. Let's look at them. First, oxygen is added to pyrite, resulting in the formation of ferum oxide and sulfur dioxide, which is used for further reactions. This interaction occurs at high temperature. Next comes the stage in which sulfur trioxide is obtained by adding oxygen in the presence of a catalyst, which is vanadium oxide. Now, at the last stage, water is added to the resulting substance, and sulfate acid is obtained. This is the most common process for the industrial extraction of sulfate acid, it is used most often because pyrite is the most accessible raw material suitable for the synthesis of the substance described in this article. Sulfuric acid obtained through this process is used in various fields industry - both in the chemical and in many others, for example, in oil refining, ore dressing, etc. Also, its use is often provided for in the manufacturing technology of many synthetic fibers.

H2SO4,lat. Acidum sulfuricum is a strong dibasic acid, molar mass about 98 g/mol.

Pure sulfuric acid is a colorless, odorless, caustic oily liquid with a density of 1.84 g/cm3, which turns into a solid crystalline mass at 10.4°C. The boiling point of aqueous solutions of sulfuric acid increases with increasing its concentration and reaches a maximum at a content of about 98% H2SO4.

Concentrated sulfuric acid reacts very violently with water, as it releases a large amount of heat (19 kcal per mole of acid) due to the formation of hydrates. For this reason, you should always dilute sulfuric acid by pouring it into water, and not vice versa.

Sulfuric acid is highly hygroscopic, that is, it absorbs water vapor from the air well, so it can be used to dry gases that do not react with it. Hygroscopicity also explains the charring of organic substances, for example, sugar or wood, when exposed to concentrated sulfuric acid. In this case, sulfuric acid hydrates are formed. Also, due to its low volatility, it is used to displace other, more volatile acids from their salts.

Concentrated sulfuric acid is a strong oxidizing agent. It oxidizes metals in the voltage series up to and including silver, and the reaction products depend on the conditions of its conduct and the activity of the metal itself. It forms two series of salts: medium - sulfates and acidic - hydrosulfates, as well as ethers.

Dilute sulfuric acid interacts with all metals located in the electrochemical voltage series to the left of hydrogen (H), releasing H2; oxidizing properties are uncharacteristic for it.

In industry, sulfuric acid is produced by two methods: the contact method using solid catalysts (contacts), and the nitrous method - with nitrogen oxides. The raw materials are sulfur, metal sulfides, etc. Several grades of acid are produced, depending on the purity and concentration: battery (the purest), technical, tower, oil of vitriol, oleum (a solution of sulfuric anhydride in sulfuric acid).

Application of sulfuric acid:

The production of mineral fertilizers is the largest area of application
Electrolyte in lead batteries
Production of synthetic detergents, dyes, plastics, hydrogen fluoride and other reagents
Ore beneficiation in the mining industry
Petroleum products purification
Metalworking, textile, leather and other industries
Production of medicinal products
IN Food Industry registered as a food additive E513
Industrial organic synthesis

Application of sulfuric acid in industry

The food industry is familiar with sulfuric acid in the form of food additive E513. The acid acts as an emulsifier. This food additive is used to make drinks. With its help, acidity is regulated. In addition to food, E513 is included in mineral fertilizers. The use of sulfuric acid in industry is widespread. Industrial organic synthesis uses sulfuric acid to carry out the following reactions: alkylation, dehydration, hydration. With the help of this acid it is restored required amount resins on filters that are used in the production of distilled water.

Use of sulfuric acid in everyday life

Sulfuric acid at home is in demand among car enthusiasts. The process of preparing an electrolyte solution for a car battery is accompanied by the addition of sulfuric acid. When working with this acid, you should remember safety rules. If acid comes into contact with clothing or open areas skin, you should wash them immediately running water. Sulfuric acid that has spilled onto metal can be neutralized with lime or chalk. When refilling a car battery, you must adhere to a certain sequence: gradually add acid to water, and not vice versa. When water reacts with sulfuric acid, the liquid becomes very hot, which can cause it to splash. Therefore, you should be especially careful not to get the liquid on your face or eyes. The acid should be stored in a tightly closed container. It is important that the chemical is kept out of the reach of children.

Use of sulfuric acid in medicine

Sulfuric acid salts are widely used in medicine. For example, magnesium sulfate is prescribed to people to achieve a laxative effect. Another derivative of sulfuric acid is sodium thiosulfate. Medicine used as an antidote in case of ingestion of the following substances: mercury, lead, halogens, cyanide. Sodium thiosulfate along with hydrochloric acid is used to treat dermatological diseases. Professor Demjanovich proposed a combination of these two drugs for the treatment of scabies. In the form of an aqueous solution, sodium thiosulfate is administered to people who suffer from allergic diseases.

Magnesium sulfate has a wide range of capabilities. Therefore, it is used by doctors of various specialties. Magnesium sulfate is administered to patients with hypertension as an antispasmodic. If a person has gallbladder disease, the substance is administered orally to improve bile secretion. The use of sulfuric acid in medicine in the form of magnesium sulfate in gynecological practice is common. Gynecologists help women in labor by administering magnesium sulfate intramuscularly, in this way they relieve pain during childbirth. In addition to all the above properties, magnesium sulfate has an anticonvulsant effect.

Application of sulfuric acid in production

Sulfuric acid, whose applications are varied, is also used in the production of mineral fertilizers. For more convenient cooperation, factories that produce sulfuric acid and mineral fertilizers are mainly located close to each other. This moment creates continuous production.

The use of sulfuric acid in the production of dyes and synthetic fibers ranks second in popularity after the production of mineral fertilizers. Many industries use sulfuric acid in some manufacturing processes. The use of sulfuric acid has found demand in everyday life. People use the chemical to service their cars. You can purchase sulfuric acid in stores that specialize in selling chemical substances, including our link. Sulfuric acid is transported in accordance with the rules for transporting such cargo. Railway or automobile transport transports acid in appropriate containers. In the first case, a tank acts as a container, in the second - a barrel or container.

Features of application and biological hazard

Sulfuric acid and related products are extremely toxic substances, which are assigned hazard class II. Their vapors affect the respiratory tract, skin, mucous membranes, causing difficulty breathing, coughing, and often laryngitis, tracheitis, and bronchitis. Maximum permissible concentration of sulfuric acid vapor in the air working area production premises- 1 mg/m3. People working with toxic acids are provided with special clothing and personal protective equipment. Concentrated sulfuric acid can cause chemical burns if handled carelessly.

If sulfuric acid is ingested, symptoms appear immediately after ingestion. sharp pains in the area of the mouth and the entire digestive tract, severe vomiting mixed with first scarlet blood, and then brown masses. Simultaneously with vomiting, a severe cough begins. A sharp swelling of the larynx and vocal cords develops, causing severe breathing difficulties. The pupils dilate, and the skin of the face takes on a dark blue color. There is a drop and weakening of cardiac activity. Death occurs at a dose of 5 milligrams. In case of sulfuric acid poisoning, urgent gastric lavage and magnesium intake are necessary.

Sulfuric acid, H2SO4, a strong dibasic acid corresponding to the highest oxidation state of sulfur (+6). Under normal conditions, it is a heavy oily liquid without color or odor. In technology, sulfuric acid is called its mixture with both water and sulfuric anhydride. If the molar ratio of SO3:H2O is less than 1, then it is an aqueous solution of sulfuric acid; if it is greater than 1, it is a solution of SO3 in sulfuric acid.

Natural deposits of native sulfur are relatively small. Total sulfur content in earth's crust is 0.1%. Sulfur is found in oil, coal, combustible and flue gases. Sulfur is most often found in nature in the form of compounds with zinc, copper and other metals. It should be noted that the share of pyrite and sulfur in the overall balance of sulfuric acid raw materials is gradually decreasing, and the share of sulfur extracted from various wastes is gradually increasing. The possibilities for obtaining sulfuric acid from waste are very significant. The use of waste gases from non-ferrous metallurgy makes it possible to obtain, without special costs in sulfuric acid systems, the roasting of sulfur-containing raw materials.

Physical and chemical properties of sulfuric acid

One hundred percent H2SO4 (SO3 x H2O) is called monohydrate. The compound does not smoke, and in concentrated form does not destroy ferrous metals, while being one of the strongest acids;

the substance has a detrimental effect on plant and animal tissues, taking away their water, as a result of which they become charred.
crystallizes at 10.45 "C;
tkip 296.2 "C;
density 1.9203 g/cm3;
heat capacity 1.62 J/g.

Sulfuric acid mixes with H2O and SO3 in any ratio, forming compounds:

H2SO4 x 4 H2O (mp - 28.36 "C),
H2SO4 x 3 H2O (mp - 36.31 "C),
H2SO4 x 2 H2O (mp - 39.60 "C),
H2SO4 x H2O (melt - 8.48 "C),
H2SO4 x SO3 (H2S2O7 - disulfuric or pyrosulfuric acid, melting point 35.15 "C) - oleum,
H2SO x 2 SO3 (H2S3O10 - trisulfuric acid, melting point 1.20 "C).

When aqueous solutions of sulfuric acid containing up to 70% H2SO4 are heated and boiled, only water vapor is released into the vapor phase. Sulfuric acid vapor also appears above more concentrated solutions. A solution of 98.3% H2SO4 (azeotropic mixture) at boiling (336.5 "C) is completely distilled. Sulfuric acid containing over 98.3% H2SO4 releases SO3 vapor when heated.
Concentrated sulfuric acid is a strong oxidizing agent. It oxidizes HI and HBr to free halogens. When heated, it oxidizes all metals except Au and platinum metals (except Pd). In the cold, concentrated sulfuric acid passivates many metals, including Pb, Cr, Ni, steel, and cast iron. Dilute sulfuric acid reacts with all metals (except Pb) preceding hydrogen in the voltage series, for example: Zn + H2SO4 = ZnSO4 + H2.

How the strong acid H2SO4 displaces weaker acids from their salts, e.g. boric acid from borax:

Na2B4O7 + H2SO4 + 5 H2O = Na2SO4 + 4 H2BO3,

and when heated, it displaces more volatile acids, for example:

NaNO3 + H2SO4 = NaHSO4 + HNO3.

Sulfuric acid removes chemically bound water from organic compounds containing hydroxyl groups- HE. Dehydration of ethyl alcohol in the presence of concentrated sulfuric acid produces ethylene or diethyl ether. The charring of sugar, cellulose, starch and other carbohydrates upon contact with sulfuric acid is also due to their dehydration. As a dibasic acid, sulfuric acid forms two types of salts: sulfates and hydrosulfates.

Freezing point of sulfuric acid:
concentration, %	freezing temp., "C
74,7	-20
76,4	-20
78,1	-20
79,5	-7,5
80,1	-8,5
81,5	-0,2
83,5	1,6
84,3	8,5
85,7	4,6
87,9	-9
90,4	-20
92,1	-35
95,6	-20

Raw materials for the production of sulfuric acid

The raw materials for the production of sulfuric acid can be: sulfur, sulfur pyrite FeS2, exhaust gases from furnaces for the oxidative roasting of sulfide ores of Zn, Cu, Pb and other metals containing SO2. In Russia, the main amount of sulfuric acid is obtained from sulfur pyrites. FeS2 is burned in furnaces, where it is in a fluidized bed state. This is achieved by quickly blowing air through a layer of finely ground pyrite. The resulting gas mixture contains SO2, O2, N2, SO3 impurities, H2O vapors, As2O3, SiO2 and others, and carries a lot of cinder dust, from which the gases are purified in electric precipitators.

Methods for producing sulfuric acid

Sulfuric acid is obtained from SO2 in two ways: nitrous (tower) and contact.

Nitrose method

The processing of SO2 into sulfuric acid using the nitrous method is carried out in production towers - cylindrical tanks (15 m or more in height) filled with a packing of ceramic rings. “Nitrose” is sprayed from above towards the gas flow - dilute sulfuric acid containing nitrosyl sulfuric acid NOOSO3H, obtained by the reaction:

N2O3 + 2 H2SO4 = 2 NOOSO3H + H2O.

Oxidation of SO2 by nitrogen oxides occurs in solution after its absorption by nitrose. Nitrose is hydrolyzed by water:

NOOSO3H + H2O = H2SO4 + HNO2.

Sulfur dioxide entering the towers forms sulfurous acid with water:

SO2 + H2O = H2SO3.

The interaction of HNO2 and H2SO3 leads to the production of sulfuric acid:

2 HNO2 + H2SO3 = H2SO4 + 2 NO + H2O.

The released NO is converted in the oxidation tower into N2O3 (more precisely, into a mixture of NO + NO2). From there, the gases enter absorption towers, where sulfuric acid is supplied from above to meet them. Nitrose is formed, which is pumped into production towers. This ensures continuity of production and circulation of nitrogen oxides. Their inevitable losses with exhaust gases are compensated by the addition of HNO3.

Sulfuric acid produced by the nitrous method has an insufficiently high concentration and contains harmful impurities (for example, As). Its production is accompanied by the release of nitrogen oxides into the atmosphere ("fox tail", named after the color of NO2).

Contact method

The principle of the contact method for the production of sulfuric acid was discovered in 1831 by P. Philips (Great Britain). The first catalyst was platinum. At the end of the 19th - beginning of the 20th centuries. the acceleration of the oxidation of SO2 to SO3 by vanadium anhydride V2O5 was discovered. A particularly important role in studying the action of vanadium catalysts and their selection was played by the studies of Soviet scientists A. E. Adadurov, G. K. Boreskov, F. N. Yushkevich.

Modern sulfuric acid plants are built to operate using the contact method. Vanadium oxides with additives SiO2, Al2O3, K2O, CaO, BaO in various proportions are used as the catalyst base. All vanadium contact masses exhibit their activity only at a temperature not lower than ~420 "C. In the contact apparatus, the gas usually passes through 4 or 5 layers of contact mass. In the production of sulfuric acid by contact method, the roasting gas is preliminarily purified from impurities that poison the catalyst. As, Se and residual dust is removed in washing towers irrigated with sulfuric acid. From the fog, sulfuric acid (formed from SO3 and H2O present in the gas mixture) is released in wet electrostatic precipitators. H2O vapors are absorbed by concentrated sulfuric acid in drying towers. Then the mixture of SO2 with air passes through a catalyst ( contact mass) and oxidizes to SO3:

SO2 + 1/2 O2 = SO3.

SO3 + H2O = H2SO4.

Depending on the amount of water entering the process, a solution of sulfuric acid in water or oleum is obtained.
About 80% of the world's H2SO4 is now produced through this method.

Application of sulfuric acid

Sulfuric acid can be used to purify petroleum products from sulfurous, unsaturated organic compounds.

In metallurgy, sulfuric acid is used to remove scale from wire, as well as sheets before tinning and galvanizing (diluted), for pickling various metal surfaces before coating them with chromium, copper, nickel, etc. Complex ores (in particular, uranium) are also decomposed using sulfuric acid.

In organic synthesis, concentrated sulfuric acid is a necessary component of nitrating mixtures, as well as a sulfonating agent in the preparation of many dyes and medicinal substances.

Sulfuric acid is widely used for the production of fertilizers, ethyl alcohol, artificial fiber, caprolactam, titanium dioxide, aniline dyes and a number of other chemical compounds.

Spent sulfuric acid (waste) is used in the chemical, metallurgical, woodworking and other industries. Battery sulfuric acid is used in the production of lead-acid power sources.

Properties of sulfuric acid

Anhydrous sulfuric acid (monohydrate) is a heavy oily liquid that mixes with water in all proportions, releasing a large amount of heat. Density at 0 °C is 1.85 g/cm3. It boils at 296 °C and freezes at - 10 °C. Sulfuric acid is called not only monohydrate, but also aqueous solutions of it (), as well as solutions of sulfur trioxide in monohydrate (), called oleum. Oleum “smoke” in air due to desorption from it. Pure sulfuric acid is colorless, while technical sulfuric acid is colored dark by impurities.

The physical properties of sulfuric acid, such as density, crystallization temperature, boiling point, depend on its composition. In Fig. Figure 1 shows a crystallization diagram of the system. The maxima in it correspond to the composition of the compounds or the presence of minima is explained by the fact that the crystallization temperature of mixtures of two substances is lower than the crystallization temperature of each of them.

Rice. 1

Anhydrous 100% sulfuric acid has a relatively high crystallization temperature of 10.7 °C. To reduce the possibility of freezing of a commercial product during transportation and storage, the concentration of technical sulfuric acid is chosen such that it has sufficient low temperature crystallization. The industry produces three types of commercial sulfuric acid.

Sulfuric acid is very active. It dissolves metal oxides and most pure metals; displaces elevated temperature all other acids are from salts. Sulfuric acid combines especially greedily with water due to its ability to form hydrates. It takes water away from other acids, from crystalline hydrates of salts and even oxygen derivatives of hydrocarbons, which contain not water as such, but hydrogen and oxygen in the combination H:O = 2. wood and other plant and animal tissues containing cellulose, starch and sugar are destroyed in concentrated sulfuric acid; the water binds with the acid and only finely dispersed carbon remains from the tissue. In dilute acid, cellulose and starch break down to form sugars. If concentrated sulfuric acid comes into contact with human skin, it causes burns.

The high activity of sulfuric acid, combined with the relatively low cost of production, predetermined the enormous scale and extreme diversity of its application (Fig. 2). It is difficult to find an industry in which sulfuric acid or products made from it were not consumed in varying quantities.

Rice. 2

The largest consumer of sulfuric acid is the production of mineral fertilizers: superphosphate, ammonium sulfate, etc. many acids (for example, phosphoric, acetic, hydrochloric) and salts are produced largely using sulfuric acid. Sulfuric acid is widely used in the production of non-ferrous and rare metals. In the metalworking industry, sulfuric acid or its salts are used for pickling steel products before painting, tinning, nickel plating, chrome plating, etc. Significant amounts of sulfuric acid are spent on refining petroleum products. The production of a number of dyes (for fabrics), varnishes and paints (for buildings and machines), medicinal substances and some plastics also involves the use of sulfuric acid. Using sulfuric acid, ethyl and other alcohols, some ethers, synthetic detergents, a range of pesticides for pest control Agriculture And weeds. Dilute solutions of sulfuric acid and its salts are used in the production of artificial silk, in textile industry for processing fibers or fabrics before dyeing them, as well as in other light industries. In the food industry, sulfuric acid is used to produce starch, molasses and a number of other products. Transport uses lead sulfuric acid batteries. Sulfuric acid is used for drying gases and for concentrating acids. Finally, sulfuric acid is used in nitration processes and in the production of most explosives.