Germanium is a rare and useful semimetal. germanium element

Named after Germany. A scientist from this country discovered and had the right to call it whatever he wanted. So in got germanium.

However, it was not Mendeleev who was lucky, but Clemens Winkler. He was assigned to study argyrodite. A new mineral, consisting mainly of, was found at the Himmelfurst mine.

Winkler determined 93% of the stone's composition and hit a dead end with the remaining 7%. The conclusion was that they included an unknown element.

More careful analysis has borne fruit. germanium discovered. This is metal. How is it useful to mankind? About this, and not only, we will tell further.

germanium properties

Germanium - 32 element of the periodic table. It turns out that the metal is included in the 4th group. The number corresponds to the valency of the elements.

That is, germanium tends to form 4 chemical bonds. This makes the element discovered by Winkler look like .

Hence the desire of Mendeleev to name the still undiscovered element ecosilicium, denoted as Si. Dmitry Ivanovich calculated the properties of the 32nd metal in advance.

Germanium is similar to silicon in chemical properties. Reacts with acids only when heated. With alkalis "communicates" in the presence of oxidizing agents.

Resistant to water vapor. Does not react with hydrogen, carbon,. Germanium lights up at a temperature of 700 degrees Celsius. The reaction is accompanied by the formation of germanium dioxide.

The 32nd element easily interacts with halogens. These are salt-forming substances from group 17 of the table.

In order not to get confused, we point out that we are focusing on the new standard. In the old, this is the 7th group of the periodic table.

Whatever the table, the metals in it are located to the left of the stepped diagonal line. The 32nd element is an exception.

Another exception is . She may also react. Antimony is deposited on the substrate.

Active interaction is ensured with. Like most metals, germanium is capable of burning in its vapors.

Externally germanium element, grayish-white, with a pronounced metallic sheen.

When considering the internal structure, the metal has a cubic structure. It reflects the arrangement of atoms in elementary cells.

They are shaped like cubes. Eight atoms are located at the vertices. The structure is close to the lattice.

Element 32 has 5 stable isotopes. Their presence is a property of all elements of the germanium subgroup.

They are even, which determines the presence of stable isotopes. For example, there are 10 of them.

The density of germanium is 5.3-5.5 grams per cubic centimeter. The first indicator is typical for the state, the second - for the liquid metal.

In a softened form, it is not only more dense, but also plastic. Brittle at room temperature, the substance becomes at 550 degrees. These are features of germanium.

The hardness of the metal at room temperature is about 6 points.

In this state, the 32nd element is a typical semiconductor. But, the property becomes "brighter" as the temperature rises. Just conductors, for comparison, lose their properties when heated.

Germanium conducts current not only in its standard form, but also in solutions.

In terms of semiconductor properties, the 32nd element is also close to silicon and is just as common.

However, the areas of application of substances differ. Silicon is a semiconductor used in solar cells, including the thin-film type.

The element is also needed for photocells. Now, consider where germanium comes in handy.

Application of germanium

Germanium is used in gamma spectroscopy. Its instruments make it possible, for example, to study the composition of additives in mixed catalyst oxides.

In the past, germanium was added to diodes and transistors. In solar cells, the properties of a semiconductor also come in handy.

But, if silicon is added to standard models, then germanium is added to highly efficient, new generation ones.

The main thing is not to use germanium at a temperature close to absolute zero. Under such conditions, the metal loses its ability to transmit voltage.

In order for germanium to be a conductor, impurities in it should be no more than 10%. Perfect Ultra Clean chemical element.

Germanium made by this method of zone melting. It is based on the different solubility of foreign elements in liquid and phases.

formula germanium allows you to apply it in practice. Here we are no longer talking about the semiconductor properties of the element, but about its ability to harden.

For the same reason, germanium has found application in dental prosthetics. Although crowns are becoming obsolete, there is still a small demand for them.

If you add silicon and aluminum to germanium, solders are obtained.

Their melting point is always lower than that of the joined metals. So, you can make complex, design designs.

Even the Internet without germanium would be impossible. The 32nd element is present in the optical fiber. In its core is quartz with an admixture of hero.

And its dioxide increases the reflectivity of the fiber. Considering the demand for it, electronics, industrialists need germanium in large volumes. Which ones, and how they are provided, we will study below.

mining germanium

Germanium is quite common. In the earth's crust, the 32nd element, for example, is more than, antimony, or.

Explored reserves are about 1,000 tons. Almost half of them are hidden in the bowels of the United States. Another 410 tons are property.

So, the rest of the countries, basically, have to buy raw materials. cooperates with the Celestial Empire. This is justified both from a political point of view and from an economic point of view.

Properties of the element germanium, associated with its geochemical relationship with widespread substances, do not allow the metal to form its own minerals.

Usually, the metal is introduced into the lattice of existing ones. The guest, of course, will not take up much space.

Therefore, you have to extract germanium bit by bit. In you can find a few kilos per ton of rock.

Enargits contain no more than 5 kilos of germanium per 1000 kilograms. In pyrargyrite 2 times more.

A ton of element 32 sulvanite contains no more than 1 kilogram. Most often, germanium is extracted as a by-product from ores of other metals, for example, or non-ferrous, such as chromite, magnetite, rutite.

Annual production of germanium ranges from 100-120 tons, depending on demand.

Basically, the single-crystal form of the substance is purchased. This is exactly what is needed for the production of spectrometers, optical fiber, precious. Let's find out the rates.

germanium price

Monocrystalline germanium is mainly purchased by the ton. For large industries, this is beneficial.

1,000 kilograms of the 32nd element costs about 100,000 rubles. You can find offers for 75,000 - 85,000.

If you take polycrystalline, that is, with smaller aggregates and increased strength, you can give 2.5 times more per kilo of raw materials.

Standard length is not less than 28 centimeters. The blocks are protected with a film, as they fade in the air. Polycrystalline germanium - "soil" for growing single crystals.

General Information and Acquisition Methods

Germanium (Ge) is a greyish-white element in a compact state and gray in a dispersed state. The existence and properties of this element were predicted in 1871 by D. I. Mendeleev, who called it ekasilicium. The new element was discovered by A. Winklsr in 1886 in Freiberg (Germany) in the mineral argyrodite 4 Ag 2 S - GeS 2 and named germanium in honor of the scientist's family. Practical interest in this element arose during the Second World War in connection with the development of semiconductor electronics. The beginning of industrial production of germanium dates back to 1945-1950.

The content of germanium in the earth's crust is 7 * 10 -4% (by mass). The main amount of the element is in a dispersed state in silicates, sulfides and minerals, which are sulfosalts. Several minerals of the sulfosalt type with a high content of germanium are known, which are not of industrial importance: argrodite-Ag 8 GeS 6 (5-7%), germanite Cu 3 (Fe, Ge, Ca, Zn) (As, S) 4 (6- 10%), reniernt (Cu, Fe) 3 (Fc, Ge, Zn, Sn) (S, As) 4 (6.37-7.8%). The sources of obtaining germanium are sulfide ores, as well as low metamorphosed coals and some iron ores (up to 0.01% Ge).

Depending on the composition of the feedstock, various methods of its primary processing are used:

Leaching with sulfuric acid followed by separation of germanium from solutions;

Sulfating firing of materials;

Sublimation of GeS sulfide or GcO monoxide in a reducing medium;

Sulfatizing firing of the material;

Reduction smelting in the presence of copper or iron;

Extraction;

Ion exchange sorption.

Germanium concentrates can be isolated from solutions in the following ways:

Precipitation in the form of sparingly soluble compounds;

Co-precipitation with hydrates of iron, zinc, with sulfides of zinc, copper, etc.;

Precipitation from sulfuric acid solutions on zinc dust (cementation).

In order to obtain germanium tetrachloride, germanium concentrates are treated with concentrated hydrochloric acid in a stream of chlorine. The resulting germanium tetrachloride (GeCI 4) is distilled off from metal chlorides having higher boiling points. As a result of the hydrolysis of purified germanium tetrachloride, germanium dioxide Qe 0 2 is obtained. Elemental germanium is obtained by reducing purified and dried dioxide with pure hydrogen. Reduced germanium is subjected to further purification from impurities by fractional crystallization Single crystals with desired electrophysical properties are grown from high-purity germanium by zone melting or by the Czochralski method. The industry produces poly- and single-crystal germanium.

Germanium grade GPZ-1 is intended for the production of single-crystal alloyed and doped germanium, as well as special purposes, grade GPZ-2 - for the production of single-crystal doped germanium and other purposes, grade GPZ-3 - for the production of alloys and blanks for optical parts. Germanium is supplied in the form of ingots in the form of a segment, each of which is packed in a plastic bag. An ingot in a polyethylene package is placed in a cardboard or plastic container and sealed with a soft gasket that ensures its safety during transportation and storage. Delivery is carried out by any type of covered transport.

Physical Properties

Atomic characteristics Atomic number 32, atomic mass 72.59 amu, atomic volume 13.64-10^ 6 m 3 /mol, atomic radius 0.139 nm, ionic radius Qe 2 + 0.065 nm, Ge 4 + 0.044 nm. Electronic structure of a free germanium atom 4s 2 p 2 . Ionization potentials / (eV): 7.88; 15.93; 34.21. Electronegativity 2.0. The crystal lattice of germanium is a cubic diamond type with a period a = 0.5657 nm. The energy of the crystal lattice is 328.5 μJ/kmol. Coordination number 4. Each germanium atom is surrounded by four neighboring ones, located at equal distances at the vertices of the tetrahedron. Bonds between atoms are carried out by paired valence electrons.

Chemical properties

In compounds, germanium exhibits an oxidation state of +2 and +4, less often +1 and +3. The normal electrode potential of the Ge reaction is -2e "= * * ± Ge 2 + f 0 \u003d - 0.45 V.

In an atmosphere of dry air, germanium is covered with a thin layer of oxides about 2 nm thick, but does not change its color. In humid air, germanium, especially polycrystalline germanium, gradually tarnishes. Noticeable oxidation begins at 500°C.

In a series of voltages, germanium is located after hydrogen - between copper and silver. Germanium does not interact with water and does not dissolve in dilute and concentrated hydrochloric acid. It dissolves in hot concentrated sulfuric acid to form Ge (S 04) u and release SO 2. When interacting with nitric acid, it forms a precipitate of germanium dioxide xGe 02- (/ H 2 0. It dissolves well in aqua regia and a mixture of HF + HNC 4. The best the solvent for germanium is an alkaline solution of hydrogen peroxide.Molten caustic alkalis quickly dissolve germanium.In this case, alkali metal germinates are formed, which are hydrolyzed by water.

GeO 2 dioxide can be obtained by calcining germanium in air, calcining sulfides, dissolving elemental germanium in 3% hydrogen peroxide in a platinum crucible, followed by evaporating the solution and calcining the residue. Ge 0 2 exists in two polymorphic modifications: low temperature a with a tetragonal lattice (1123°C) and high temperature d with a hexagonal lattice (above 1123°C). The melting point of Ge 0 2 is 1725°C. Upon melting, a transparent melt is formed. Germanium dioxide dissolves in water with the formation of germanic acid HggeO3, is easily transferred into a solution with alkalis to form salts of germanic acid - germanates. Under the action of hydrogen peroxide on concentrated solutions of "ep-manates, salts of pergermanic acids are obtained, forming crystalline hydrates, for example Na 2 Ge 0 5 -4 H 2 0.

There are several compounds of germanium with hydrogen. The existence of GeH, a dark, easily exploding powder, has been established. Also known are compounds of the german type GenH 2 „+ 2 (for example, Ge 2 H 4 , Ge 2 He), which are volatile at low values ​​of n. Monogermane GeH 4 is a colorless gas with a boiling point of 88.9 °C. Dngermane and tngermane exist in the liquid phase at room temperature and normal pressure. The solubility of hydrogen in germanium at 800 °C does not exceed 1.5-10 -7% (et.).

Carbon is practically insoluble in germanium. In liquid germanium near the melting point, the solubility of carbon is estimated at 0.23% (at.). According to various authors, the concentration of carbon in single-crystal germanium has been determined from 7*10 -4 to 5.2*10 -3%.

When germanium is heated to 700-750 ° C in nitrogen or NH 3, Ge 3 N 4 and Ge 3 N 2 are formed. Germanium nitride Ge 3 N 2 is a dark brown crystals that are easily hydrolyzed. Thermal decomposition into elements begins at 500 °C. More stable is Ge 2 N 4 nitride, which decomposes above 1000 °C.

The direct interaction of germanium with halogens begins at about 250 °C. GeCl 4 tetrachloride, the main intermediate product in the production of semiconductor germanium, is of the greatest practical importance. With iodine, germanium forms Gel 4 iodide, a yellow substance with a melting point of 146°C and a boiling point of 375°C. Gel 4 is used to produce high-purity germanium by transport reactions. The halides are unstable to water.

Among compounds with sulfur, GeS 2 disulfide is known, which is released from strongly acidic solutions of tetravalent germanium salts when an intense current of hydrogen sulfide is passed. Crystalline GcS 2 is white flakes with a pearly sheen, the melt solidifies into an amber-yellow transparent mass and reveals semiconductor properties. The melting point of GeS 2 is -825 ° С. Germanium monosulfide GeS exists in amorphous and single-crystal states. Crystalline GeS is dark gray in color, melts at 615 "C. All germanium chalcogens (sulfides, selenides and tellurides) exhibit semiconductor properties. With phosphorus, germanium gives the GeP compound.

Technological properties

Germanium is characterized by relatively high hardness, high brittleness, and therefore cannot be subjected to cold working by pressure. Deformation is possible at temperatures close to the melting point and under conditions of all-round uneven compression.

With a diamond saw, a germanium ingot can be sawn into thin slices. The surface of the plates is polished with a fine corundum powder on glass and polished on a felt with a suspension of aluminum oxide.

Areas of use

Germanium plays an exceptional role in radio electronics. It is used for the manufacture of crystalline rectifiers (diodes) and crystalline amplifiers (triodes), which are used in computers, telemechanics, radar installations, etc.

On the basis of germanium, high-power rectifiers with high efficiency have also been created for rectifying alternating current of ordinary frequency, designed for currents up to 10,000 A and above.

Germanium triodes are widely used to amplify, generate or convert electrical oscillations.

In radio engineering, film resistances from 1000 ohms to several megaohms have become widespread.

Due to a significant change in conductivity under the action of radiation, germanium is used in various photodiodes and photoresistors.

Germanium finds application for the manufacture of thermistors (in this case, the strong temperature dependence of the electrical resistance of germanium is used).

In nuclear technology, germanium detectors are used for radiation.

Gold-doped germanium lenses are an integral part of infrared technology devices. Special optical glasses with a high refractive index are made from germanium dioxide. Germanium is also introduced into the composition of alloys for highly sensitive thermocouples.

The consumption of germanium as a catalyst in the production of artificial fiber is increasing significantly.

A number of compounds of germanium with transition metals have a high transition temperature to the superconducting state, in particular, materials based on the Nb 3 Ge compound (T „>22 K).

It is assumed that some germanium organic compounds are biologically active: they delay the development of malignant tumors, lower blood pressure, and have an analgesic effect.

In 1870 D.I. Mendeleev, on the basis of the periodic law, predicted an as yet undiscovered element of group IV, calling it ekasilicium, and described its main properties. In 1886, the German chemist Clemens Winkler, during a chemical analysis of the mineral argyrodite, discovered this chemical element. Initially, Winkler wanted to name the new element "neptunium", but this name had already been given to one of the proposed elements, so the element was named after the scientist's homeland - Germany.

Being in nature, getting:

Germanium is found in sulfide ores, iron ore, and is found in almost all silicates. The main minerals containing germanium: argyrodite Ag 8 GeS 6, confieldite Ag 8 (Sn,Ce)S 6, stottite FeGe(OH) 6, germanite Cu 3 (Ge,Fe,Ga)(S,As) 4, rhenierite Cu 3 ( Fe,Ge,Zn)(S,As) 4 .
As a result of complex and time-consuming operations for enrichment of ore and its concentration, germanium is isolated in the form of GeO 2 oxide, which is reduced with hydrogen at 600°C to a simple substance.
GeO 2 + 2H 2 \u003d Ge + 2H 2 O
Germanium is purified by zone melting, which makes it one of the most chemically pure materials.

Physical properties:

Gray-white solid with a metallic luster (mp 938°C, bp 2830°C)

Chemical properties:

Under normal conditions, germanium is resistant to air and water, alkalis and acids, it dissolves in aqua regia and in an alkaline solution of hydrogen peroxide. The oxidation states of germanium in its compounds: 2, 4.

The most important connections:

Germanium(II) oxide, GeO, grey-black, slightly sol. in-in, when heated, it disproportionates: 2GeO \u003d Ge + GeO 2
Germanium(II) hydroxide Ge(OH) 2 , red-orange. crystal,
germanium(II) iodide, GeI 2 , yellow cr., sol. in water, hydrol. bye.
Germanium(II) hydride, GeH 2 , tv. white por., easily oxidized. and decay.

Germanium(IV) oxide, GeO 2 , white crystals, amphoteric, obtained by hydrolysis of chloride, sulfide, germanium hydride, or by the reaction of germanium with nitric acid.
Germanium(IV) hydroxide, (germanic acid), H 2 GeO 3 , weak. unst. biaxial to-ta, germanate salts, for example. sodium germanate, Na 2 GeO 3 , white crystal, sol. in water; hygroscopic. There are also Na 2 hexahydroxogermanates (ortho-germanates), and polygermanates
Germanium(IV) sulfate, Ge(SO 4) 2 , colorless. cr., hydrolyzed by water to GeO 2, obtained by heating germanium (IV) chloride with sulfuric anhydride at 160 ° C: GeCl 4 + 4SO 3 \u003d Ge (SO 4) 2 + 2SO 2 + 2Cl 2
Germanium(IV) halides, fluoride GeF 4 - bests. gas, raw hydrol., reacts with HF, forming H 2 - germanofluoric acid: GeF 4 + 2HF \u003d H 2,
chloride GeCl 4 , colorless. liquid, hydr., bromide GeBr 4 , ser. cr. or colorless. liquid, sol. in org. conn.,
iodide GeI 4, yellow-orange. cr., slow. hydr., sol. in org. conn.
Germanium(IV) sulfide, GeS 2 , white kr., poorly sol. in water, hydrol., reacts with alkalis:
3GeS 2 + 6NaOH = Na 2 GeO 3 + 2Na 2 GeS 3 + 3H 2 O, forming germanates and thiogermanates.
Germanium(IV) hydride, "german", GeH 4 , colorless gas, organic derivatives of tetramethylgermane Ge(CH 3) 4 , tetraethylgermane Ge(C 2 H 5) 4 - colorless. liquids.

Application:

The most important semiconductor material, the main areas of application: optics, radio electronics, nuclear physics.

Germanium compounds are slightly toxic. Germanium is a microelement that in the human body increases the efficiency of the body's immune system, fights cancer, and reduces pain. It is also noted that germanium promotes the transfer of oxygen to the tissues of the body and is a powerful antioxidant - a blocker of free radicals in the body.
The daily requirement of the human body is 0.4–1.5 mg.
Garlic is the champion in germanium content among food products (750 micrograms of germanium per 1 g of dry mass of garlic cloves).

The material was prepared by students of the Institute of Physics and Chemistry of Tyumen State University
Demchenko Yu.V., Bornovolokova A.A.
Sources:
Germanium//Wikipedia./ URL: http://ru.wikipedia.org/?oldid=63504262 (date of access: 06/13/2014).
Germanium//Allmetals.ru/URL: http://www.allmetals.ru/metals/germanium/ (date of access: 06/13/2014).

At the time the periodic table was created, germanium had not yet been discovered, but Mendeleev predicted its existence. And 15 years after the report, an unknown mineral was discovered in one of the Freiberg mines, and in 1886 a new element was isolated from it. The credit belongs to the German chemist Winkler, who gave the element the name of his homeland. Even with the many useful properties of germanium, among which there was a place for healing, they began to use it only at the beginning of World War II, and even then not very actively. Therefore, even now it cannot be said that the element is well studied, but some of its abilities have already been proven and successfully applied.

The healing properties of germanium

The element is not found in its pure form, its isolation is laborious, therefore, at the first opportunity, it was replaced with cheaper components. At first it was used in diodes and transistors, but silicon turned out to be more convenient and affordable, so the study of the chemical properties of germanium continued. Now it is part of thermoelectric alloys, used in microwave devices, infrared technology.

Medicine also became interested in a new element, but a significant result was obtained only at the end of the 70s of the last century. Japanese specialists managed to discover the medicinal properties of germanium and outline ways to use them. After testing on animals and clinical observations of the effect on humans, it turned out that the element is capable of:

• stimulate;
• deliver oxygen to tissues;
• fight tumors;
• increase the conduction of nerve impulses.

The complexity of use lies in the toxicity of germanium in large doses, so a drug was required that could have a positive effect on certain processes in the body with minimal harm. The first was "Germanium-132", which helps to improve the immune status of a person, helps to avoid lack of oxygen in the event of a drop in hemoglobin levels. Experiments also showed the effect of the element on the production of interferons, which resist rapidly dividing (tumor) cells. The benefit is observed only when administered orally, wearing jewelry with germanium will not give any effect.

The lack of germanium reduces the body's natural ability to withstand external influences, which leads to various disorders. The recommended daily dose is 0.8-1.5 mg. You can get the necessary element with the regular use of milk, salmon, mushrooms, garlic and beans.

Mini - abstract

"Element Germanium"

Target:

Describe the element Ge

Give a description of the properties of the element Ge

Tell about the application and use of this element

Element history ……….………………………………….……. one

Element properties …..……………………………………..…… 2

Application ……………….….…………………………………….. 3

Health hazard ………..………………………....… 4

Sources ………………………….…………………….…………… 5

From the history of the element..

Ggermanium(lat. Germanium) - a chemical element of group IV, the main subgroup of the periodic system of D.I. Mendeleev, denoted by the symbol Ge, belongs to the family of metals, serial number 32, atomic mass 72.59. It is a gray-white solid with a metallic luster.

The existence and properties of Germany were predicted in 1871 by Mendeleev and named this still unknown element - "Ekasilicon" because of the similarity of its properties with silicon.

In 1886, the German chemist K. Winkler, while examining the mineral, found that some unknown element was present in it, which was not detected by analysis. After hard work, he discovered the salts of a new element and isolated a certain amount of the element itself in its pure form. In the first report of the discovery, Winkler suggested that the new element was analogous to antimony and arsenic. Winkler intended to name the element Neptunium, but that name had already been given to one falsely discovered element. Winkler renamed the element he discovered to germanium (Germanium) in honor of his fatherland. And even Mendeleev, in a letter to Winkler, strongly supported the name of the element.

But until the second half of the 20th century, the practical use of Germany remained very limited. The industrial production of this element arose in connection with the development of semiconductor electronics.

Element propertiesGe

For medical needs, germanium was the first to be used most widely in Japan. Tests of various organogermanium compounds in animal experiments and in human clinical trials have shown that they positively affect the human body to varying degrees. The breakthrough came in 1967 when Dr. K. Asai discovered that organic germanium has a wide range of biological effects.

Properties:

Carries oxygen in the tissues of the body - germanium in the blood behaves similarly to hemoglobin. It is involved in the process of oxygen transfer to the tissues of the body, which guarantees the normal functioning of all body systems.

stimulates the immune system - germanium in the form of organic compounds promotes the production of gamma-interferons, which inhibit the reproduction of rapidly dividing microbial cells, and activates specific immune cells (T-cells)

antitumor - germanium delays the development of malignant neoplasms and prevents the appearance of metastases, and also has protective properties against radiation exposure.

biocidal (antifungal, antiviral, antibacterial) - germanium organic compounds stimulate the production of interferon - a protective protein produced by the body in response to the introduction of foreign bodies.

Application and Use of the Element Germanium in Life

In industrial practice, germanium is obtained mainly from by-products of the processing of non-ferrous metal ores. Germanium concentrate (2-10% Germany) is obtained in various ways, depending on the composition of the raw material. To isolate very pure germanium, which is used in semiconductor devices, metal is melted by zone. Single-crystal germanium, necessary for the semiconductor industry, is usually obtained by zone melting.

It is one of the most valuable materials in modern semiconductor technology. It is used to make diodes, triodes, crystal detectors, and power rectifiers. Germanium is also used in dosimetric devices and devices that measure the intensity of constant and variable magnetic fields. An important field of application of the element is infrared technology, in particular the production of infrared radiation detectors. Many alloys containing germanium are promising for practical use. For example, glasses based on GeO 2 and other Ge compounds. At room temperature, germanium is resistant to air, water, alkali solutions, and dilute hydrochloric and sulfuric acids, but is easily soluble in aqua regia and in an alkaline solution of hydrogen peroxide. And nitric acid oxidizes slowly.

Germanium alloys, which have high hardness and strength, are used in jewelry and denture technology for precision castings. Germanium is present in nature only in the bound state and never in the free state. The most common germanium-bearing minerals are argyrodite and germanite. Large reserves of germanium minerals are rare, but the element itself is widely found in other minerals, especially in sulfides (most often in zinc sulfides and silicates). Small amounts are also found in different types of hard coal.

World production Germany is 65 kg per year.

health hazard

Occupational health problems can be caused by dust dispersion during loading of germanium concentrate, grinding and loading of dioxide to isolate germanium metal, and loading of powdered germanium for remelting into bars. Other sources of harm to health are thermal radiation from tube furnaces and from the process of melting powdered germanium into bars, as well as the formation of carbon monoxide.

Absorbed germanium is rapidly excreted from the body, mainly in the urine. There is little information on the toxicity of inorganic germanium compounds to humans. Germanium tetrachloride is a skin irritant. In clinical trials and other long-term cases of oral administration of cumulative doses up to 16 g of spirogermanium, an organic germanium antitumor drug, or other germanium compounds, neurotoxic and nephrotoxic activity has been noted. Such doses are usually not subjected to production conditions. Animal experiments to determine the effects of germanium and its compounds on the body have shown that the dust of metallic germanium and germanium dioxide, when inhaled in high concentrations, leads to a general deterioration in health (limitation of weight gain). Morphological changes similar to proliferative reactions were found in the lungs of animals, such as thickening of the alveolar sections and hyperplasia of the lymphatic vessels around the bronchi and blood vessels. Germanium dioxide does not irritate the skin, but upon contact with the moist mucous membrane of the eye, it forms germanic acid, which acts as an ocular irritant. Long-term intraperitoneal injections at doses of 10 mg/kg lead to changes in peripheral blood .

The most harmful germanium compounds are germanium hydride and germanium chloride. Hydride can cause acute poisoning. Morphological examination of the organs of animals that died during the acute phase revealed disorders in the circulatory system and degenerative cellular changes in the parenchymal organs. Thus, hydride is a multipurpose poison that affects the nervous system and the peripheral circulatory system.

Germanium tetrachloride is a strong respiratory, skin, and eye irritant. Threshold concentration - 13 mg / m 3. At this concentration, it suppresses the pulmonary response at the cellular level in experimental animals. In high concentrations, it leads to irritation of the upper respiratory tract and conjunctivitis, as well as changes in the frequency and rhythm of breathing. Animals that survived acute poisoning developed catarrhal desquamative bronchitis and interstitial pneumonia a few days later. Germanium chloride also has a general toxic effect. Morphological changes were observed in the liver, kidneys and other organs of animals.

Sources of all information provided