Molybdenum - what is it? Molybdenum - a characteristic of the functions and role of the element in the human body; a list of products that contain this metal.

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Properties of molybdenum very helpful to people. After all molybdenum, added to alloys, increases their resistance to chipping. Knives and other items for cutting, as well as drills are made exclusively from steels with an admixture of rare metal. Interestingly, the technology was forgotten for centuries. Until the 19th century, scientists tried to unravel the secret of Japanese samurai swords, forged in the Middle Ages. At the turn of the 20th century, physicists and chemists finally discovered the presence of molybdenum in tool steel. It was he who made the swords exceptionally strong and durable.

Molybdenum formula My.Element does not occur in pure form. The content of molybdenum in minerals is evenly dispersed in the earth's crust, which makes mining impractical. Sometimes only accumulations of molebdenite ore are found. Its largest field is being developed in the US state of Colorado.

In order to avoid chipping on the tools, a 6% addition of molybdenum to the alloy is required. This element is also known for making parts more resistant to high temperatures. Many factory furnaces and other containers that generate steam, for example, are made from molybdenum alloys. They are also used in the automotive industry for camshafts and valves.

Fittings, pipes require molybdenum "infusions" to improve anti-corrosion properties. Compounds with metal are the only ones suitable for aircraft production. Passenger liners of our time are impressive in size. Steel without an "additive" does not stretch to such parameters only under the condition of a thick wall. Aircraft require thin sheets. These can only be obtained from alloys with molybdenum.

At temperatures from 600 to 900 degrees Celsius molybdenum metal actively oxidized and formed molybdenum oxide. It absorbs oxygen when neon and argon are carried over its surface. So people purify these noble gases from excess impurities.

Without molybdenum, there would be wrong fur coats and sheepskin coats. Metal is added to tanning mixtures. For them, salts of molybdic acid are used. Without the recipe, it would not have been possible to obtain such soft and supple skin.

Even the oil industry is based on molybdenum. It is necessary for the cracking of organics. This is the name of the process of splitting oil.

In education, the mineral molybdenite is revered. It, like graphite, is used for pencil leads. The mineral is very soft. Its structure is scaly. At the slightest pressure, the scales are separated, remaining on paper in the form of letters and other symbols.

People of art also turn to metal with a lead luster. The element is added to coloring compositions, in particular, enamel. With molybdenum in the composition, it is easier, a thinner layer is distributed over the treated surface, better adheres to it.

Jewelers have learned to replace platinum with molybdenum. The metal looks like a noble element in appearance, it does not oxidize at ordinary temperatures. Those who make jewelry are going to take advantage of the discovery made by US physicists.

They didn't stop at resemblance simple element with precious. Scientists have changed the lattice of molybdenum, bringing it as close as possible to platinum. For the experiments, it took a nickel compound with the hero of the article and nitrogen. In the presence of this gas, the molecular lattice of molybdenum expanded, the density of electrons in it increased. These are the characteristics of platinum.

The Americans experimented, hoping to create new electrocatalysts needed in the energy sector. Now parts are made of platinum, which is very expensive. The opening will reduce the costs of industrialists, and, consequently, consumers. Jewelers will be able not only to replace platinum, but in fact, to create its artificial counterpart.

The word "molybdenum" is Greek. On ancient language the concept means "lead". Its luster is similar to the glow of metal No. 42. So the Swedish chemist Scheele called molybdenum molybdenum. The scientist isolated it in the form of oxide in 1778. The pure metal was already obtained by another chemist, Scheele's compatriot, Gjelm. It happened in 1782. It was then that molybdenum oxide was reduced with carbon, which led to the appearance of a metal with a lead luster without any impurities.

Russia has 10 deposits of element No. 42. Seven mines are being developed on an industrial scale. Metal is also mined in neighboring China. 7 provinces of China are proud of molybdenum: Shanxi, Liaoning, Hebei, Jilin, Jiangxi, Shandong and Henan. There are deposits in Canada. The United States is inferior in terms of the number of deposits, but, as already mentioned, it ranks first in terms of the reserves of molybdenum occurring in Colorado.

Molybdenum is needed not only by industrialists, but also by the body. Metal is a constant component of living beings. Element No. 42 regulates metabolic processes, retains fluoride in the organs, thereby helping the teeth to remain strong. Without molybdenum, cells are not able to grow and develop. The metal promotes the synthesis of ascorbic acid, ensures normal tissue respiration. There will be no breath, there will be no life. By the way, that is why it is not on Mars, scientists suggest. They claim that life did not originate on the red planet because there was no molybdenum.

The body needs 75-300 microkilograms per day. Both smaller and larger doses are harmful. A storehouse of molybdenum is leafy vegetables, grains, legumes, sunflower seeds and garlic. So, the latter not only protects against colds and improves immunity. Garlic also helps to produce red herbal bodies, starts cell respiration and more.

The role of molybdenum in the human body

In the human body, molybdenum is found in small amounts, so it belongs to the trace elements. Often, the reserve of molybdenum is stored in the liver, thyroid gland, kidneys, gray matter of the brain. The body of an adult contains no more than 9 mg of the trace element.

Adsorption of the element from food occurs in the stomach and small intestine. Up to 80% of molybdenum is absorbed from food. After that, the compounds are transported through the blood supply to the cells and tissues. Excess metal is excreted in bile, feces and urine.

Functions of molybdenum:

Participates in the metabolism of proteins, carbohydrates and fats, removes excess uric acid from the body.
It is part of the enzymes sulfite oxidase, xanthine oxidase, aldehyde oxidase.
Improves nitrogen absorption, accelerates the synthesis of amino acids.
Neutralizes purines, pteridines, pyrimidines, promotes the elimination of toxic substances from the body. Molybdenum promotes purification from alcohol and sulfites.
Normalizes the work of the pancreas.
It normalizes the functions of the reproductive system, it is necessary to improve sexual functions in men.
Takes part in oxygen exchange. This important component cellular respiration systems.
Participates in the production of red blood cells in the blood.
Protects the body from inflammation, activates the work of anti-inflammatory substances (for example, vitamin C).
It is a powerful antioxidant.
Prevention of anemia, dysbacteriosis, caries.
Stimulates growth, so molybdenum deficiency is dangerous for children and adolescents.
Promotes the absorption of ferrum (iron) by the body.
Increases the activity of leukocytes, improves the immune system.

Molybdenum deficiency in children leads to stunting. Such babies are distinguished by a frail physique and reduced appetite. In adults, the risk of developing gout, urolithiasis, oncology increases, in men - impotence.

Molybdenum is actively used to treat diseases of the gastrointestinal tract (gastrointestinal tract), respiratory and musculoskeletal systems. Preparations with molybdenum are prescribed to improve immunity and normalize reproductive function.

The main sources of the mineral

Plant sources (Table 1):

Green vegetables (spinach, lettuce, cabbage, sorrel, broccoli). Also carrots, cucumbers, green onion, garlic, tomatoes.
Legumes (lentils, peas, beans, soybeans).
Cereal crops (buckwheat, barley, oats, rye, wheat).
Black currant, gooseberry, raspberry.
Sunflower seeds.
cocoa beans.

Animal sources (Table 1):

Poultry meat, lamb, beef, pork.
Milk and dairy products.
Sea fish, seafood.
Eggs.
Meat by-products (liver, kidneys).

Table salt is also a source of molybdenum. The daily dose of molybdenum, filed in Table. 2.

Table 1. The content of molybdenum in products


beef liver	110
Soya	95
Peas	83
Beef kidneys	82
Beans	76
chicken liver	55
Grain wheat	42
Egg	40
Buckwheat	36
Milk	35
Cold smoked fish	26
Black currant	24
squids	20
Green onion	19
Wheat groats	17
Chicken	16
Raspberries	14
Gooseberry	11

With prolonged cooking of vegetables and defrosting meat in water, molybdenum is lost. Enrich your diet with dairy products, fresh vegetables and fruits, healthy pastries - and you will not experience a mineral deficiency

Table 2. Daily norm of molybdenum

Molybdenum in higher dosages is taken:

With tumors.
With infertility and hormonal disorders.
Tachycardia, caries and visual impairment.

Interaction with other elements

Features of the reaction with other nutrients:

Incompatible with sulfur and copper - they bind and remove molybdenum from the body. Copper sulfate accelerates the excretion of molybdenum compounds with bile.
Taking drugs with sodium, lead and tungsten reduce the absorption of molybdenum.
Molybdenum is responsible for the utilization of iron, so these drugs should not be taken at the same time.
With an excess of molybdenum, the synthesis of vitamin B12 is disrupted. It is also undesirable to take these drugs at the same time.
Compatible with most vitamins of group A,,,,.

Molybdenum deficiency

Molybdenum deficiency is not often diagnosed, since in many areas vegetables and fruits are grown on lands in which molybdenum content is several times higher than normal. In part, our body compensates for the lack of molybdenum from water and air: the compounds of this microelement are easily soluble, they are quickly absorbed and spread throughout the body. An interesting fact is that molybdenum does not accumulate in the body of animals.

Causes of molybdenum deficiency:

Violation of the exchange of molybdenum.
Frequent stress.
Unbalanced nutrition.
Diseases in which you have to eat parenterally.
Excess content in the body of heavy metals that displace molybdenum.

Symptoms of a lack of molybdenum:

Nervousness, sleep problems, high excitability.
Tachycardia.
Violation of protein metabolism.
Weakening of vision, inability to distinguish objects at dusk.
Headache.
Bleeding gums and mouth.
Children have growth retardation.
Seizures.
In the urine, the level of xanthine and sulfite increases.

Prolonged deficiency is manifested by nausea, vomiting, general deterioration. The risk of developing cancer increases.

First of all, you need to undergo a complete examination and adjust the diet. Most often, molybdenum deficiency develops against the background of other diseases. You can take drugs with a high content of this trace element only as directed by a doctor.

Excess molybdenum

A toxic dose is 10 mg, a lethal dose is 50 mg. It is almost impossible to obtain such an amount of molybdenum from products. An excess of this element is diagnosed extremely rarely, because normally the body itself takes care of maintaining the proper level of the mineral.

Reasons for excess:

Drug abuse.
Work in hazardous industries.
Lack of copper in the diet.

Overdose symptoms:

Violation of reproductive functions.
Irritation of mucous membranes.
Change in skin pigmentation.
Slimming.
Salts are deposited in the joints.
The percentage of uric acid in the urine increases.

In the future, this is fraught with the development of anemia, uraturia, leukopenia and other diseases. Doctors take blood for analysis (normally, 0.3-1.2 micrograms of molybdenum should be per liter) and hair samples. After that, treatment with sulfur and iron preparations is prescribed - these elements remove excess molybdenum from the body and temporarily block absorption.

Preparations with molybdenum

There is no dosage form with molybdenum, since the deficiency of this element can be eliminated with the help of a proper diet and pharmacy dietary supplements (biologically active additives) and vitamins.

Molybdenum is included in the complexes: Multi Tabs, MultiMax, Gerimaks, Alfavit, Vitrum, Centuri 2000, Duovit, StayHealthy, etc.

The role of molybdenum in human life and its main sources, see the video below.

Molybdenum is widely used in the metallurgical industry as an alloying element in the production of special steels.
Molybdenum is also used as the main component of heat-resistant alloys, especially in last years in connection with the development of gas turbine construction (gas turbines, rockets, jet engines, etc.).
Molybdenum additives increase strength, elastic limit, creep resistance at elevated temperatures, and corrosion resistance become.
Pure molybdenum in the form of tape and wire is used for heaters in electric resistance furnaces and in the form of tin in the vacuum and radio engineering industries. Molybdenum carbide is used in the manufacture of hard alloys.
In the chemical industry, molybdenum is used to produce dyes and special compounds that increase the fire resistance of fabrics and wood impregnated with them, as well as in the manufacture of fertilizers for Agriculture(crystals containing 97% molybdenum dihydrate), catalysts and lubricants (molybdenum disulphite).
Molybdenum can be rolled, stamped and forged.
Molybdenum powder obtained by reduction of molybdenum trioxide or ammonium compound of molybdenum in a hydrogen atmosphere serves source material to obtain metal rods, which are used for the manufacture of alloys or the production of bars, wire, sheets, pipes and other products from pure molybdenum.
Molybdenum, intended for the production of special alloys, is produced according to the specifications of TsMTU 4787-56 of high purity with a molybdenum content of 99.98%; impurities of tin, lead, cadmium, bismuth and antimony should not exceed 0.0001% each; copper, zinc, magnesium, aluminum, silicon, arsenic, sulfur and phosphorus - 0.001% and iron - 0.005%, and the total impurities should be less than 0.02%.
Currently, molybdenum of 99.99% purity is obtained on a semi-industrial scale.
High-purity molybdenum is produced in the form of powder or square-section rods with dimensions from 10x10 to 25x25 mm and a length of 350-460 mm.
Molybdenum rods intended for the production of wire, rods, sheets, pipes and other products are manufactured according to the specifications TUOR 7-53 with a cross section of at least 14.5x14.5 mm and a length of more than 450 mm. Chemical composition such rods should be (% to metal): not more than 0.03 R2O3 (the sum of oxides of trivalent metals), 0.03 Si02, 0.005 nickel and 0.008 magnesium oxide and calcium; the rest is molybdenum.
Since metallic molybdenum is obtained by the cermet method, the properties of molybdenum depend on its preliminary processing.
The mechanical properties of molybdenum depending on the state are given in table. 39.

The main disadvantage of molybdenum is its high oxidation rate at high temperatures (in an air stream at 1000 °, the oxidation rate is 0.5-1.25 mm / h), already at a temperature of about 800 °, molybdenum oxide M0O3 is formed on the metal surface, which evaporates with a significant speed. In dry air at 500° molybdenum hardly oxidizes. To protect the surface of molybdenum from oxidation, it is plated with other metals (nickel, an alloy of platinum with rhodium, etc.) or alloyed with certain elements that prevent the formation of MOO3.
Oxygen is a harmful impurity in molybdenum and no more than 0.003% is allowed. With a higher oxygen content, the molybdenum oxide released during cooling of the metal and located along the grain boundaries imparts brittleness to it and makes it unsuitable for pressure treatment.
The development of high-temperature technology required the creation of molybdenum alloys with a high recrystallization temperature, high hardness and strength at elevated temperatures, and good corrosion resistance. Alloy additives have made it possible to significantly improve the properties of molybdenum at high temperatures.
The effect of various additives at room temperature on the hardness of molybdenum is shown in fig. 43, and at elevated temperatures - in fig. 44.

The tensile strength and elongation of some molybdenum alloys depending on the annealing temperature are shown in fig. 45.
It has been established that alloying additives with a larger atomic radius than that of molybdenum strongly inhibit recrystallization in solid solutions, while those with a smaller atomic radius have little effect on recrystallization. For example, zirconium (atomic radius 1.55 A) significantly increases the recrystallization temperature with a slight addition to molybdenum, and niobium (atomic radius 1.43 A) begins to affect recrystallization with its additions above 1%. Additions of beryllium, manganese, vanadium and chromium greatly increase the molybdenum recrystallization temperature.
Alloying additives significantly improve mechanical properties molybdenum alloys, increase their corrosion resistance, strength and hardness at high temperatures. Alloys of molybdenum with silicon have high heat resistance at high temperatures (1500 °).
Molybdenum with the addition of 0.5% titanium has more satisfactory strength at temperatures above 800° than other alloys.
Chromium in the amount of 1.2% somewhat reduces the oxidizability of molybdenum at high temperatures, but makes molybdenum brittle, reducing its ability to be forged. Molybdenum, containing 0.1% beryllium, lends itself well to heat treatment.

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(eng. Molybdenum, lat. Molybdaenum) is one of chemical elements periodic system of Mendeleev, metal. It was discovered at the end of the 18th century, but initially this new metal had many impurities, and only a few decades later, in 1817, the Swedish scientist J. Berzelius managed to obtain pure molybdenum and study its properties.

Molybdenum: element

Element molybdenum(denoted as Mo) refers to the subgroup of secondary elements of group 6 of group 5 of the period of the periodic table and occupies position 42 in it. This metal is a simple malleable silver-gray substance.

Thanks to his appearance and lead-like physical and chemical properties, molybdenum and got its name ("molybdos" in ancient Greek and means "lead"). Initially, it was not distinguished from lead luster and graphite, calling all these substances " molybdenum«.

In the form of various compounds, it is relatively evenly distributed in the thickness earth's crust, and is also present in river and sea water, plant ash. The largest deposits of this metal are located in Russia, Armenia, Chile, Mexico, USA, Canada, Norway and Australia.

Products with molybdenum

Main sources molybdenum products of plant origin act, and its content in products directly depends on the soil on which they grow. Fortunately, in Russia there is a shortage molybdenum in the soil - a rather rare phenomenon, therefore, with a balanced diet and a normal state of human health, a lack of this microelement does not threaten him.

So the richest molybdenum the following products:

berries - rose hips, raspberries, gooseberries, black currants;
cocoa beans and;
cereals - buckwheat, wheat, rice, rye, millet, barley, oats;
green leafy vegetables - cabbage (broccoli, white cabbage, kohlrabi, Brussels sprouts, cauliflower), spinach, sorrel;
corn;
peas;
lentils;
beans;
nuts - nutmeg, pistachios;
mushrooms (including, and);
seaweed - , .

Among animal products molybdenum is in:

dairy products;
pork and beef liver;
eggs.

Molybdenum: composition

How does it help you molybdenum? Your feedback is very important for newbies!

Molybdenum (Mo) - belongs to the category of refractory rare metals, atomic number - 42, atomic mass - 95.95, density - 9.3 g / cm3, melting point - 2622 ° C, linear expansion coefficient - 5.49.10-6, specific electrical conductivity - 22.7 m / ohm.mm2, specific electrical resistance- 0.0478 ohm / mm2.m (15OS); 0.62 (2000OS), modulus of elasticity - 35kg / mm2, tensile strength - 140 - 160kg / mm2, relative elongation - 10-18% (up to 100OS); 0%(1000OS); for a single crystal - 30%, yield strength - 41-61kg / mm2, Brinell hardness - 160-180kg / mm2 (unannealed); 240 - 250kg/mm2(rolled).

Molybdenum was discovered in 1778 by the Swedish chemist K. Scheele, while working with the mineral molybdenite, which got its name from the Greek word "molybdos", which means lead, due to the low hardness of molybdenite and lead-gray color. Scheele isolated molybdic acid, and in 1781, metallic molybdenum was smelted in a high-temperature furnace.

Molybdenum is not widely distributed in nature - 3.10-4%, it is characterized by high dispersion. In nature, molybdenum is found mainly in copper-molybdenum ores. The content of molybdenum in ores is usually hundredths, even thousandths, and very rarely tenths of a percent. A valuable natural companion of molybdenum in copper-molybdenum ores is rhenium, which is extracted at the enrichment stage into molybdenum concentrate. There are 20 molybdenum minerals known, but 98% of molybdenum is mined from molybdenite. The most important deposits of molybdenum contain this metal in the form of the mineral molybdenite or molybdenum luster (MoSO2), less often molybdenum occurs in the form of wulfenite (PbMoH4) and powelite (CaMoO4).

Chemically pure molybdenum is a greyish-white, refractory metal. Molybdenum lends itself well to machining, molybdenum is a good conductor of electricity.

Compact metallic molybdenum is stable in air up to a temperature of about 400°C; at a higher temperature, molybdenum is intensively oxidized. Molybdenum reacts with atmospheric nitrogen only at a temperature of 1500 ° C, with carbon, CO - it reacts starting from 800 ° C. Halides react with molybdenum: fluorine - in the cold, chlorine - with dark red heat, bromine - with light red heat, iodine - does not react. Sulfur, up to 440OS, does not affect metallic molybdenum.

The action of acids: HNO3 concentrated - slowly corrodes, HNO3 diluted - quickly dissolves, H2SO4 concentrated cold - has little effect, H2SO4 hot (200-250OS) - quickly dissolves. Boiling concentrated HCl - dissolves vigorously, dilute HCl dissolves more intensively strong, in HF (strong, cold and hot) - molybdenum is stable. A good molybdenum solvent: 5 volumes of HNO3 + 3 volumes of H2SO4 + 2 volumes of H2O.

The action of alkalis: in cold solutions, molybdenum is stable, in hot solutions it corrodes somewhat. Molten alkalis in the presence of oxidizing agents (PbO2, KNO3 and others) intensively oxidize metallic molybdenum.

RECEIVING.

Molybdenum ores are enriched by flotation and gravity methods, the resulting concentrate contains up to 85% MoS. Harmful impurities in the concentrate and the permissible limits of their content: not more than 0.5% As, Sb, Bi and Ba, not more than 0.2% Co and Cu, not more than 0.5% P and Sn. The concentrate is calcined to oxide MO2 and repeatedly leached with ammonia. Leaching is carried out in hermetically sealed drum-type iron apparatuses or in special vats equipped with agitators. The solution is freed from impurities by the addition of ammonium polysulphide, filtered, and evaporated. During cooling, crystals of ammonium molybdate precipitate out of the solution, purified by recrystallization and treated with hydrochloric acid for further purification and conversion of molybdenum to molybdic acid, after calcination of which pure molybdenum anhydride (MoO3) is obtained.

Powdered molybdenum metal is obtained by reducing the anhydride in a stream of hydrogen, then the powder is pressed, sintered and forged into rods.

In general, metallurgical processing of molybdenum concentrates can be carried out to obtain ferromolybdenum for ferrous metallurgy or to obtain chemical compounds of various composition and purity - molybdenum MoO3, ammonium paramolybdate, sodium molybdate, calcium used in the production of compact molybdenum, alloyed steels and cast irons or in the chemical industry.

Indispensable integral part of all generally accepted schemes for processing molybdenum concentrates is their oxidative roasting, for the transfer of molybdenum from the sulfide form to the oxide form - molybdenum trioxide MoO3. Further processing of the cinder depends on the purpose and type of the final product of the metallurgical technology. For alloying steels and cast irons, ferromolybdenum, CaMoO4 and molybdenum trioxide MoO3 are commonly used. The main method of processing cinder to ferromolybdenum is metallothermic melting using silicon and aluminum as reducing agents.

The technology for obtaining compact malleable molybdenum from calcined concentrates includes the following main technological operations: obtaining pure molybdenum trioxide, obtaining molybdenum powder by reducing MoO3, converting molybdenum into a compact state by melting or powder metallurgy methods.

Possible direct decomposition of molybdenum concentrates without prior roasting, such as nitric acid, autoclave leaching in an alkaline solution or other methods.

Physical methods for cleaning molybdenum are based on the volatility of molybdenum oxide MoO3. The technical product of the molybdenum concentrate is melted and the vapors of MoO3 oxide are driven off from it by the air supplied to the furnace, which are then condensed in a special refrigerator. The molybdenum oxide thus obtained has a purity of up to 99.9%. The main method for obtaining metallic molybdenum, as well as tungsten, is based on the reduction of molybdenum oxide MoO3 with hydrogen. This method does not introduce additional contamination, providing pure metal. Sometimes even molybdenum concentrates are reduced with hydrogen, but the metal is contaminated with various impurities.

Molybdenum oxides, as well as tungsten oxides, can be reduced with carbon and carbon-containing gases, but the metal formed by this method contains up to 5% carbides and various impurities.

The resulting molybdenum metal powder is converted into a compact metal by methods similar to those used to obtain compact tungsten. The process is carried out in the same apparatus, but with different temperature conditions. The first sintering is carried out at a temperature of 1200°C in a hydrogen atmosphere. High-temperature sintering of molybdenum rods is carried out in the same apparatus as welding of tungsten rods at a temperature of 2200-2400°C.

Machining of molybdenum bars, consisting of forging and drawing, or rolling onto a sheet, is carried out on the same equipment as for tungsten, at forging and drawing temperatures of 1200 ° C, i.e. lower than tungsten. To obtain large ingots and billets, molybdenum is melted in vacuum electric arc furnaces. An electric arc is initiated between a sintered molybdenum powder electrode and liquid metal in a water-cooled copper mold.

APPLICATION.

Approximately 90-95% of the mined molybdenum is used in metallurgy, as an alloying addition in steel and special alloys. Additives increase the hardenability of steel, give it a uniform fine-grained structure, increase its ductility, strength, wear resistance and toughness. Molybdenum-alloyed steels are divided into general-purpose alloyed or structural steels (up to 10 kilograms of molybdenum is consumed per 1 ton of steel) and special-purpose alloyed steels - stainless, heat-resistant (consumption per ton of steel up to 70 kilograms of molybdenum), high-speed (molybdenum consumption up to 80 kilogram per ton). Structural steels alloyed with molybdenum are used in the automotive, tractor, aviation, boiler and turbine industries. Hardened steels of high strength and ductility are used to make armor and gun barrels. About half of the world's molybdenum goes to the production of alloys and a quarter - to steel. Molybdenum is used in the preparation of superhard alloys - stellites. Pure metallic molybdenum is used in radio engineering and electrical engineering, in radio equipment, in X-ray tubes, in rocket science, and in the manufacture of parts for nuclear reactors.

Approximately one twentieth of the metallic molybdenum is used in the chemical, oil refining, ceramic, glass textile industries, and in medicine. Molybdenum trioxide is used to purify oil products from harmful impurities, the addition of molybdenum to glass gives it refractoriness.

In its pure form, molybdenum is used in the form of a tape or wire for the manufacture of heating elements operating in a hydrogen atmosphere at temperatures up to 1600 ° C. Molybdenum thin sheet and wire are widely used in the radio-electronic industry and X-ray engineering, for the manufacture of parts for electronic lamps, X-ray tubes and other electronic devices. Large ingots of molybdenum are used for the manufacture of turbine blades and critical parts of rocket engines and rocket bodies.

Molybdenum, which is characterized by high strength and low capture of thermal neutrons, can serve as a structural material in nuclear power reactors. In the glass industry, molybdenum is used as electrodes (heaters), stirrers and other parts of furnaces for melting glass.

In relatively small quantities, in various industries, a number of chemical compounds of molybdenum are used. MoS2 disulfide and MoSe2 diselenide are used as lubricants for friction parts operating in the temperature range from -45 to +400°C.

Chemical compounds of molybdenum are also used as pigments in the paint and varnish and light industries for the manufacture of paints and varnishes for dyeing fabrics and furs.

Alloys of molybdenum with cobalt and chromium are used in surgery to replace damaged joints. Molybdenum is a part of plant and animal organisms, being a necessary element of their life and development.

The confirmed world reserves of molybdenum at the beginning of 2014 amount to 11 million tons, in total, up to 39 million tons of molybdenum are contained in the bowels of the earth's crust. In total in the world, today, about 270 thousand tons of molybdenum are mined per year. In the Russian Federation, molybdenum reserves are estimated at 0.25 million tons, and 4.8 thousand tons are mined per year. Russian molybdenum deposits are characterized by a significantly lower quality of ores than in foreign countries- the average content of molybdenum in them is 0.058%.

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