Where is barium mined?

BARIUM – chemical element of the 2nd group of the periodic system, atomic number 56, relative atomic mass 137,33. Located in the sixth period between cesium and lanthanum. Natural barium consists of seven stable isotopes with mass numbers 130(0,101%), 132(0,097%), 134(2,42%), 135(6,59%), 136(7,81%), 137(11,32. 138%) and 71,66 (2%). Barium in most chemical compounds exhibits a maximum oxidation state of +XNUMX, but can also have a zero oxidation state. In nature, barium occurs only in the divalent state.

History of discovery.

Also on the topic: In 1602, Casciarolo (Bolognese shoemaker and alchemist) picked up a stone in the surrounding mountains that was so heavy that Casciarolo suspected it was gold. Trying to isolate gold from a stone, the alchemist calcined it with coal. Although it was not possible to isolate gold, the experiment brought clearly encouraging results: the cooled calcination product glowed reddish in the dark. The news of such an unusual find created a real sensation in the alchemical community and the unusual mineral, which received a number of names – sunstone (Lapis solaris), Bolognese stone (Lapis Boloniensis), Bolognese phosphorus (Phosphorum Boloniensis) became a participant in various experiments. But time passed, and gold did not even think of standing out, so interest in the new mineral gradually disappeared, and for a long time it was considered a modified form of gypsum or lime. Only a century and a half later, in 1774, the famous Swedish chemists Karl Scheele and Johan Hahn carefully studied the “Bologna stone” and found that it contained some kind of “heavy earth”. Later, in 1779, Guiton de Morveau named this “land” barote from the Greek word “barue” – heavy, and later changed the name to baryte. Under this name, barium earth appeared in chemistry textbooks of the late 18th and early 19th centuries. For example, in the textbook by A.L. Lavoisier (1789), barite is included in the list of salt-forming earthy simple bodies, and another name for barite is given – “heavy earth” (terre pesante, Latin terra ponderosa). The still unknown metal contained in the mineral began to be called barium (Latin – Barium). In Russian literature of the 19th century. The names barite and barium were also used. The next known barium mineral was natural barium carbonate, discovered in 1782 by Withering and later named witherite in his honor. Barium metal was first prepared by Englishman Humphry Davy in 1808 by electrolysis of wet barium hydroxide with a mercury cathode and subsequent evaporation of mercury from barium amalgam. It should be noted that in the same 1808, somewhat earlier than Davy, barium amalgam was obtained by the Swedish chemist Jens Berzelius. Despite its name, barium turned out to be a relatively light metal with a density of 3,78 g/cm 3, so in 1816 the English chemist Clark proposed rejecting the name “barium” on the grounds that if barium earth (barium oxide) is indeed heavier than other earths (oxides), then the metal, on the contrary, is lighter than other metals. Clark wanted to name this element plutonium in honor of the ancient Roman god, ruler of the underground kingdom of Pluto, but this proposal did not meet with support from other scientists and the light metal continued to be called “heavy.”

Barium in nature.

The earth’s crust contains 0,065% barium, it occurs in the form of sulfate, carbonate, silicates and aluminosilicates. The main barium minerals are the aforementioned barite (barium sulfate), also called heavy or Persian spar, and witherite (barium carbonate). The world’s mineral resources of barite were estimated in 1999 at 2 billion tons, a significant part of them concentrated in China (about 1 billion tons) and Kazakhstan (0,5 billion tons). There are large reserves of barite in the USA, India, Turkey, Morocco and Mexico. Russian barite resources are estimated at 10 million tons, its production is carried out at three main deposits located in Khakassia, Kemerovo and Chelyabinsk regions. The total annual production of barite in the world is about 7 million tons, Russia produces 5 thousand tons and imports 25 thousand tons of barite per year.

Receiving.

Also on the topic: The main raw materials for the production of barium and its compounds are barite and, less commonly, witherite. By reducing these minerals with coal, coke or natural gas, barium sulfide and barium oxide are obtained, respectively: BaSO₄ + 4C = BaS + 4CO Also on the topic: BaCO₃ + C = BaO + 2CO Barium metal is obtained by reducing it with aluminum oxide. This process was first carried out by the Russian physical chemist N.N. Beketov. This is how he described his experiments: “I took anhydrous barium oxide and, adding to it a certain amount of barium chloride, like flux, I put this mixture along with pieces of clay (aluminum) in a carbon crucible and heated it for several hours. After cooling the crucible, I found in it a metal alloy of a completely different type and physical properties than clay. This alloy has a coarse-crystalline structure, is very brittle, a fresh fracture has a faint yellowish sheen; analysis showed that at 100 hours it consisted of 33,3 barium and 66,7 clay, or, otherwise, for one part of barium it contained two parts of clay. ” Currently, the reduction process with aluminum is carried out in a vacuum at temperatures from 1100 to 1250 ° C, while the resulting barium evaporates and condenses on the cooler parts of the reactor. In addition, barium can be obtained by electrolysis of a molten mixture of barium and calcium chlorides.

Simple substance.

Barium is a silvery-white malleable metal that shatters when struck sharply. Melting point 727° C, boiling point 1637° C, density 3,780 g/cm 3 . At normal pressure it exists in two allotropic modifications: a -Ba with a cubic body-centered lattice is stable up to 375° C; b -Ba is stable above 375° C. At elevated pressure, a hexagonal modification is formed. Metal barium has high chemical activity; it oxidizes intensively in air, forming a film containing BaO, BaO₂ and Ba₃N₂, with slight heating or impact, it ignites. Therefore, barium is stored under a layer of kerosene or paraffin. Barium reacts vigorously with water and acid solutions, forming barium hydroxide or the corresponding salts: With halogens, barium forms halides; with hydrogen and nitrogen, when heated, it forms hydride and nitride, respectively. Barium metal dissolves in liquid ammonia to form a dark blue solution, from which ammonia Ba(NH) can be isolated₃)₆ – crystals with a golden luster, easily decompose with the release of ammonia. In this compound, barium has zero oxidation state.

Application in industry and science.

The use of barium metal is very limited due to its high chemical reactivity; barium compounds are used much more widely. An alloy of barium with aluminum – an Alba alloy containing 56% Ba – is the basis of getters (absorbers of residual gases in vacuum technology). To obtain the getter itself, barium is evaporated from the alloy by heating it in a evacuated flask of the device, as a result of which a “barium mirror” is formed on the cold parts of the flask. In small quantities, barium is used in metallurgy to purify molten copper and lead from impurities of sulfur, oxygen and nitrogen. Barium is added to printing and antifriction alloys; an alloy of barium and nickel is used to make parts for radio tubes and spark plug electrodes in carburetor engines. In addition, there are non-standard uses of barium. One of them is the creation of artificial comets: barium vapor released from a spacecraft is easily ionized by solar rays and turns into a bright plasma cloud. The first artificial comet was created in 1959 during the flight of the Soviet automatic interplanetary station Luna-1. In the early 1970s, German and American physicists, conducting research on the Earth’s electromagnetic field, released 15 kilograms of tiny barium powder over Colombia. The resulting plasma cloud stretched along the magnetic field lines, making it possible to clarify their position. In 1979, jets of barium particles were used to study the aurora.

Barium compounds.

Divalent barium compounds are of greatest practical interest. Оксид бария (BaO): an intermediate product in the production of barium – a refractory (melting point about 2020 ° C) white powder, reacts with water, forming barium hydroxide, absorbs carbon dioxide from the air, turning into carbonate: When calcined in air at a temperature of 500–600° C, barium oxide reacts with oxygen, forming peroxide, which, upon further heating to 700° C, again transforms into an oxide, eliminating oxygen: This is how oxygen was obtained until the end of the 19th century, until a method for releasing oxygen by distilling liquid air was developed. In the laboratory, barium oxide can be prepared by calcining barium nitrate: Now barium oxide is used as a water-removing agent, to obtain barium peroxide and to make ceramic magnets from barium ferrate (for this, a mixture of barium and iron oxide powders is sintered under a press in a strong magnetic field), but the main use of barium oxide is the manufacture of thermionic cathodes. In 1903, the young German scientist Wehnelt tested the law of the emission of electrons by solids, discovered shortly before by the English physicist Richardson. The first of the experiments with platinum wire completely confirmed the law, but the control experiment failed: the flow of electrons sharply exceeded the expected one. Since the properties of the metal could not change, Wehnelt assumed that there was some kind of impurity on the surface of the platinum. After testing possible surface contaminants, he became convinced that the additional electrons were emitted by barium oxide, which was part of the lubricant of the vacuum pump used in the experiment. However, the scientific world did not immediately recognize this discovery, since its observation could not be reproduced. Only almost a quarter of a century later, the Englishman Kohler showed that in order to exhibit high thermionic emission, barium oxide must be heated at very low oxygen pressures. This phenomenon could only be explained in 1935. The German scientist Pohl suggested that electrons are emitted by a small impurity of barium in the oxide: at low pressures, part of the oxygen evaporates from the oxide, and the remaining barium is easily ionized to form free electrons, which leave the crystal when heated: 2BaO = 2Ba + O₂; Ba = Ba 2+ + 2е The correctness of this hypothesis was finally established in the late 1950s by Soviet chemists A. Bundel and P. Kovtun, who measured the concentration of barium impurity in the oxide and compared it with the flux of thermionic electron emission. Now barium oxide is the active part of most thermionic cathodes. For example, a beam of electrons that forms an image on a TV screen or computer monitor is emitted by barium oxide. Barium hydroxide, octahydrate (Ba(OH)₂·8H₂O). White powder, highly soluble in hot water (more than 50% at 80° C), worse in cold water (3,7% at 20° C). The melting point of the octahydrate is 78° C; when heated to 130° C, it turns into anhydrous Ba(OH)₂. Barium hydroxide is produced by dissolving the oxide in hot water or by heating barium sulfide in a stream of superheated steam. Barium hydroxide easily reacts with carbon dioxide, so its aqueous solution, called “barite water,” is used in analytical chemistry as a reagent for CO₂. In addition, “barite water” serves as a reagent for sulfate and carbonate ions. Barium hydroxide is used to remove sulfate ions from plant and animal oils and industrial solutions, to obtain rubidium and cesium hydroxides, as a component of lubricants. Barium carbonate (BaCO₃). In nature, the mineral is witherite. White powder, insoluble in water, soluble in strong acids (except sulfuric acid). When heated to 1000° C, it decomposes with the release of CO₂: Barium carbonate is added to glass to increase its refractive index and is added to enamels and glazes. Barium sulfate (BaSO₄). In nature – barite (heavy or Persian spar) – the main mineral of barium – is a white powder (melting point about 1680 ° C), practically insoluble in water (2,2 mg / l at 18 ° C), slowly dissolves in concentrated sulfuric acid. The production of paints has long been associated with barium sulfate. True, at first its use was of a criminal nature: crushed barite was mixed with lead white, which significantly reduced the cost of the final product and, at the same time, deteriorated the quality of the paint. However, such modified whites were sold at the same price as regular whites, generating significant profits for dye plant owners. Back in 1859, the Department of Manufactures and Domestic Trade received information about the fraudulent machinations of Yaroslavl factory owners who added heavy spar to lead white, which “deceives consumers about the true quality of the product, and a request was also received to prohibit the said manufacturers from using spar in the production of lead white.” ” But these complaints came to nothing. Suffice it to say that in 1882 a spar plant was founded in Yaroslavl, which in 1885 produced 50 thousand pounds of crushed heavy spar. In the early 1890s, D.I. Mendeleev wrote: “. In many factories, barite is added to the mixture of whitewash, since whitewash imported from abroad contains this mixture to reduce the price.” Barium sulfate is part of lithopone, a non-toxic white paint with high hiding power, widely in demand on the market. To make lithopone, aqueous solutions of barium sulfide and zinc sulfate are mixed, during which an exchange reaction occurs and a mixture of fine-crystalline barium sulfate and zinc sulfide – lithopone – precipitates, and pure water remains in the solution. BaS + ZnSO₄ = BaSO₄ Ї + ZnS Ї In the production of expensive grades of paper, barium sulfate plays the role of a filler and weighting agent, making the paper whiter and denser; it is also used as a filler for rubber and ceramics. More than 95% of the barite mined in the world is used to prepare working solutions for drilling deep wells. Barium sulfate strongly absorbs x-rays and gamma rays. This property is widely used in medicine for diagnosing gastrointestinal diseases. To do this, the patient is allowed to swallow a suspension of barium sulfate in water or its mixture with semolina porridge – “barium porridge” and is then exposed to x-rays. Those parts of the digestive tract through which the “barium porridge” passes appear as dark spots in the picture. This way the doctor can get an idea of ​​the shape of the stomach and intestines and determine the location of the disease. Barium sulfate is also used to make barite concrete, used in the construction of nuclear power plants and nuclear plants to protect against penetrating radiation. Barium sulfide (Low). Intermediate product in the production of barium and its compounds. The commercial product is a gray friable powder, poorly soluble in water. Barium sulfide is used to produce lithopone, in the leather industry to remove hair from hides, and to produce pure hydrogen sulfide. BaS is a component of many phosphors – substances that glow after absorbing light energy. This is what Casciarolo obtained by calcining barite with coal. By itself, barium sulfide does not glow: it requires the addition of activating substances – salts of bismuth, lead and other metals. Barium titanate (BaTiO₃). One of the most industrially important compounds of barium is a white, refractory (melting point 1616 ° C) crystalline substance, insoluble in water. Barium titanate is obtained by fusing titanium dioxide with barium carbonate at a temperature of about 1300° C: Barium titanate is one of the best ferroelectrics ( cm. also FERROELECTRICS), very valuable electrical materials. In 1944, Soviet physicist B.M. Vul discovered extraordinary ferroelectric abilities (very high dielectric constant) of barium titanate, which retained them in a wide temperature range – almost from absolute zero to +125 ° C. This circumstance, as well as great mechanical strength and The moisture resistance of barium titanate has contributed to its becoming one of the most important ferroelectrics, used, for example, in the manufacture of electrical capacitors. Barium titanate, like all ferroelectrics, also has piezoelectric properties: it changes its electrical characteristics under pressure. When exposed to an alternating electric field, oscillations occur in its crystals, and therefore they are used in piezoelements, radio circuits and automatic systems. Barium titanate was used in attempts to detect gravitational waves.

Other barium compounds.

Nitrate and chlorate (Ba(ClO₃)₂) barium is an integral part of fireworks, the addition of these compounds gives the flame a bright green color. Barium peroxide is a component of ignition mixtures for aluminothermy. Barium tetracyanoplatinate(II) (Ba[Pt(CN)₄]) glows when exposed to x-rays and gamma rays. In 1895, the German physicist Wilhelm Roentgen, observing the glow of this substance, suggested the existence of a new radiation, later called X-rays. Now barium tetracyanoplatinate(II) is used to cover luminous instrument screens. Barium thiosulfate (BaS₂O₃) gives colorless varnish a pearly tint, and by mixing it with glue, you can achieve a complete imitation of mother-of-pearl.

Toxicology of barium compounds.

All soluble barium salts are poisonous. Barium sulfate used in fluoroscopy is practically non-toxic. The lethal dose of barium chloride is 0,8–0,9 g, barium carbonate is 2–4 g. When poisonous barium compounds are ingested, a burning sensation in the mouth, pain in the stomach, salivation, nausea, vomiting, dizziness, muscle weakness, and shortness of breath occur. , slow heart rate and drop in blood pressure. The main treatment for barium poisoning is gastric lavage and the use of laxatives. The main sources of barium entering the human body are food (especially seafood) and drinking water. According to the recommendation of the World Health Organization, the barium content in drinking water should not exceed 0,7 mg/l; in Russia, much more stringent standards apply – 0,1 mg/l. Yuri Krutyakov Also on the topic:
References: Figurovsky N.A. The history of the discovery of elements and the origin of their names. M., Nauka, 1970
Venetsky S.I. About rare and scattered. Tales of Metals. M., Metallurgy, 1980
Popular library of chemical elements. Under. ed. I.V. Petryanova-Sokolova. M., Nauka, 1983
Information and analytical review. State and prospects of the global and domestic markets for non-ferrous, rare and precious metals. Issue 18. Barite. M., 2002 The mineral Barite or “heavy spar” is a naturally occurring barium sulfate. It is used primarily as a weighting agent for drilling fluids (more than 75% of consumption), an inert and low-active filler in the paint, rubber, paper, glass, cement, construction industries, in the production of plastics, ceramics, (16-18%) and as chemical raw materials for the production of barium compounds (6-7%). After the collapse of the USSR, most of the sources of barite ended up outside of Russia in Kazakhstan, Azerbaijan and Georgia. Even taking into account the decline in consumption as a result of the permanent economic crisis and the partial replacement of barite weighting material with hematite, there remains a serious shortage of barite, covered by import supplies. In Russia, barite mining is carried out by:

• JSC “Salairsky GOK” on the basis of the sulfide-barite deposit Kvartsitovaya Sopka in the Kemerovo region with an annual production of up to 125 thousand tons of barite concentrate;
• CJSC “Khoylinsky GOK” has been leading work at the Khoylinsky barite deposit in the Komi Republic since 2001 with the production capacity of the first stage of the processing plant up to 100 thousand tons of concentrate;
• CJSC “Barit” at the Tolcheinsky barite deposit in the Republic of Khakassia with an annual output of up to 3,5 thousand tons, with the possibility of expansion to 100 thousand tons;
• JSC “Uchalinsky GOK” at the Molodezhny sulfide-barite deposit in the Chelyabinsk region;
• CJSC Barit-gaz is preparing to develop the Medvedev barite deposit in the Chelyabinsk region.

In Russia, there is a shortage of barite filler grades, which is covered by imports amounting to 19-30 thousand tons per year (see Table 1) in the amount of 1,6-5,5 million US dollars.

Table 1. Dynamics of barite commodity flows in Russia for 1996-2002.

Production, thousand tons

Net consumption, thousand tons

The dynamics of barite imports into Russia is extremely unstable (see Table 2). Continuously growing supplies are made from Kazakhstan alone (45% of Russian imports). Supplies from other countries vary sharply over time, both in volume and in cost. By 2000, supplies from Azerbaijan, Kyrgyzstan and Georgia had completely stopped. There are also one-time large deliveries, for example, from Singapore and Slovakia. The problem of such unstable import flows of barite must be solved – either by replacing them from Russian sources, or by organizing new stable flows from regular partners.

The main consumption of barite in Russia is in the production of weighting agents for drilling fluids (with a consumption of up to 19 kg per 1 ton of solution). If its consumption increases to 35 kg/t of solution (the level adopted in the USA), then Russian demand for barite concentrates may increase to 350-400 thousand tons per year.

Dependence on imports can be eliminated by accelerating the search and development of new barite deposits with high-quality ores, as well as introducing new enrichment technologies at existing mining enterprises.

Table 2. Dynamics of barite imports in Russia for 1996-2002, thousand tons

Other barite deposits have been preliminarily assessed near existing enterprises: Novo-Urskoye and Beloklyuchevskoye – near the Salair Mining and Processing Plant, Malokhoylinskoye – near the Khoylinsky Mining and Processing Plant, Kuten-Bulukskoye – near the Tolcheinsky mine of Barit CJSC in Khakassia.

It is also possible to discover new deposits of barite, both within the known Palarno-Ural and Altai-Sayan barite-bearing provinces, and in new areas that were not previously considered as promising for barite – the Ural (Middle and Southern Urals), Yenisei (Krasnoyarsk Territory) , Transbaikal (Chita region), Far Eastern (in the Khabarovsk and Primorsky territories) and Kolyma (northeastern part of the Republic of Sakha-Yakutia and southwestern part of the Magadan region).

Considering the increase in the volume of drilling work during the exploration and development of new oil and gas fields in Russia, the problem of increasing the deficit in demand for barite remains unresolved, which is especially important in conditions of instability of import flows. There are all the prerequisites for solving it by intensifying exploration work for new rich barite deposits and involving them in production.