Beryllium

Bezeichnung:Beryllium

CAS-Nr7440-41-7

Englisch Name:Beryllium

CBNumberCB4226453

SummenformelBeH2

Molgewicht11.03

MOL-Datei7440-41-7.mol

Synonyma

Beryllium

Glucinium

Beryllium physikalisch-chemischer Eigenschaften

Schmelzpunkt	1278 °C (lit.)
Siedepunkt	2970 °C (lit.)
Dichte	1.85 g/mL at 25 °C (lit.)
storage temp.	Store at +15°C to +25°C.
Aggregatzustand	powder
Farbe	Gray
PH	0.5 (H2O, 20°C)
Widerstand (resistivity)	4.46 μΩ-cm, 20°C
Wasserlöslichkeit	soluble acids except HNO3; soluble alkalies [HAW93]
Merck	13,1164
Expositionsgrenzwerte	TLV-TWA 0.002 mg/m³ (ACGIH, MSHA, and OSHA).
Stabilität	Stable. Incompatible with acids, bases, oxidizing agents, halogen compounds, halogens, alkali metals.
CAS Datenbank	7440-41-7(CAS DataBase Reference)
EPA chemische Informationen	Beryllium (7440-41-7)

Sicherheit

Kennzeichnung gefährlicher	T+,T
R-Sätze:	49-25-26-36/37/38-43-48/23-20
S-Sätze:	53-45
RIDADR	UN 1567 6.1/PG 2
WGK Germany	1
RTECS-Nr.	DS1750000
Selbstentzündungstemperatur	1198 °F
TSCA	Yes
HS Code	3822 00 00
HazardClass	8
PackingGroup	III
Giftige Stoffe Daten	7440-41-7(Hazardous Substances Data)
Toxizität	Elemental Be and its compounds are very poisonous by inhalation or intravenous route. Chronic inhalation of beryllium dusts or fumes can cause a serious lung disease, berylliosis, after a latent period ranging from several months to many years. Inhalation of airborne dusts can also cause an acute disease manifested as dyspnea, pneumonitis and tracheobronchitis with a short latency period of a few days. Skin contact with soluble salts of the metal can cause dermatitis. Beryllium also is a carcinogen. There is sufficient evidence of its inducing cancer in animals and humans. It is one of the US EPA's listed priority pollutant metals in the environment.
IDLA	4 mg Be/m3

Gefahreninformationscode (GHS)

Beryllium Chemische Eigenschaften,Einsatz,Produktion Methoden

ERSCHEINUNGSBILD
GRAUES BIS WEISSES PULVER.
PHYSIKALISCHE GEFAHREN
Staubexplosion der pulverisierten oder granulierten Substanz in Gemischen mit Luft möglich.
CHEMISCHE GEFAHREN
Reagiert mit starken Säuren und starken Basen unter Bildung brennbarer/explosionsfähiger Gase (z.B. Wasserstoff, ICSC-Nr. 0001). Bildet schlagempfindliche Gemische mit einigen chlorierten Lösemitteln wie Kohlenstofftetrachlorid und Trichlorethylen.
ARBEITSPLATZGRENZWERTE
TLV: 0.002 mg/m?(als TWA), 0.01 mg/m?(als STEL); Krebskategorie A1(bestätigte krebserzeugende Wirkung beim Menschen); Beabsichtigte änderung 0.00002 mg/m?Haut, Inhal. Sensibilisierung (ACGIH 2005).
MAK: Sensibilisierung der Atemwege und der Haut; Krebserzeugend Kategorie 1; (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation des Aerosols und durch Verschlucken.
INHALATIONSGEFAHREN
Verdampfung bei 20°C vernachlässigbar; eine gesundheitsschädliche Partikelkonzentration in der Luft kann jedoch beim Dispergieren schnell erreicht werden.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION:
Das Aerosol dieser Substanz reizt die Atemwege. Inhalation des Staubes oder Rauches kann zu chemischer Pneumonie führen. Exposition kann zum Tod führen. Die Auswirkungen treten u.U. verzögert ein. ärztliche Beobachtung notwendig.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
Wiederholter oder andauernder Kontakt kann zu Hautsensibilisierung führen. Risiko der Lungenschädigung bei wiederholter oder längerer Exposition gegenüber Staubpartikeln mit nachfolgender chronischer Berylliumkrankheit (Husten, Gewichtsverlust, Schwäche). Krebserzeugend für den Menschen.
LECKAGE
Gefahrenbereich verlassen! Fachmann zu Rate ziehen! Verschüttete Substanz sorgfältig in Behältern sammeln; falls erforderlich vorher Anfeuchten. An sicheren Ort bringen. Chemikalienschutzanzug mit umgebungsluftunabhängigem Atemschutzgerät. NICHT in die Umwelt gelangen lassen.
R-Sätze Betriebsanweisung:
R49:Kann Krebs erzeugen beim Einatmen.
R25:Giftig beim Verschlucken.
R26:Sehr giftig beim Einatmen.
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
R43:Sensibilisierung durch Hautkontakt möglich.
R48/23:Giftig: Gefahr ernster Gesundheitsschäden bei längerer Exposition durch Einatmen.
R20:Gesundheitsschädlich beim Einatmen.
S-Sätze Betriebsanweisung:
S53:Exposition vermeiden - vor Gebrauch besondere Anweisungen einholen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
Beschreibung
Beryllium is widely distributed in the earth's crust at trace concentration, 2.8 mg/kg. The element was first discovered by Vauquelin in 1797. Wohler and Bussy in 1828 independently isolated beryllium in the metallic form from its oxide. In nature, beryllium occurs in several minerals, mostly combined with silica and alumina. The most common minerals are beryl, 3BeO•Al2O3•6SiO2; chrysoberyl, BeO•Al2O3; phenacite, 2BeO•SiO2; and bertrandite, 4BeO•2SiO2•H2O. Also, it is found in trace amounts in the ore feldspar, and in volcanic ash. It's abundance in the sea water is estimated in the range 5.6 ppt.

Beryllium oxide is a component of precious stones, emerald, aquamarine and topaz. Beryllium is utilized in nuclear reactors to moderate the velocity of slow neutrons. It is hot-pressed to appropriate shapes and sizes that yield high strength and ductility for its applications.
Chemische Eigenschaften
Grayish metal; hexagonal close-packed crystal system, lattice constant, a=2.286 Å and c=3.584 Å; density 1.85 g/cm3; permeable to x-rays; highly ductile; modulus to weight ratio very high, elastic modulus 44.5 x 106 at 25°C (for hot-pressed block and sheet); melting point 1,287°C; vaporizes at 2,471°C; sound transmission velocity 12,600 m/sec; reflectivity (white light) 55%; thermal neutron absorption cross-section 0.0090 barns/atom; electrode potential, Be/Be2+(aq) 1.85 V; electrical resistivity 3.36 x 10–10 ohm.m (at 20°C).
Chemische Eigenschaften
Beryllium is a brittle, steel-gray metal found as a component of coal, oil, certain rock minerals, volcanic dust, and soil. It reacts with strong acids and strong bases forming flammable/explosive gas. It has several applications in the aerospace, nuclear, and manufacturing industries. In addition, beryllium is amazingly versatile as a metal alloy where it is used in dental appliances, golf clubs, non-sparking tools, wheel chairs, and electronic devices. Beryllium is used in alloys with a number of metals, including steel, nickel, magnesium, zinc, and aluminum, the most widely used alloy being beryllium-copper—properly called “a bronze”—which has a high tensile strength and a capacity for being hardened by heat treatment. Beryllium bronzes are used in non-spark tools, electrical switch parts, and watch springsOne of the largest uses of the metal is as a moderator of thermal neutrons in nuclear reactors and as a refl ector to reduce the leakage of neutrons from the reactor core. A mixed uranium-beryllium source is often used as a neutron source. As a foil, beryllium is used as window material in x-ray tubes. Its lightness, high elastic modulus, and heat stability make it an attractive material for the aircraft and aerospace industry. Berylliumores are used to make special ceramics for electrical and high-technology applications. Beryllium alloys are used in automobiles, computers, sports equipment (golf clubs and bicycle frames), and dental bridges. It used in nuclear reactors as a refl ector or moderator because it has a low thermal neutron absorption cross section. It is used in gyroscopes, computer parts, and instruments where lightness, stiffness, and dimensional stability are required. The oxide has a very high melting point and is also used in nuclear work and ceramic applications. Normally, the general population is exposed to low levels of beryllium in air, food, and water. People working in industries where beryllium is mined, processed, machined, or converted into metal, alloys, and other chemicals, may be exposed to high levels of beryllium. People living near these industries may also be exposed to higher than normal levels of beryllium in air. People living near uncontrolled hazardous waste sites may be exposed to higher than normal levels of beryllium.
Chemische Eigenschaften
Beryllium is a gray shiny metal or powder, or fine granules which resemble powdered aluminum. Beryllium is slightly soluble in water. All beryllium compounds are soluble in water, to some degree. Berylore is the primary source of beryllium, although there are numerous other sources.
Physikalische Eigenschaften
The name beryllium comes from the Greek word for be rullos, beryl, and from the Prakrit veruliya, in allusion to become pale in reference to the pale semiprecious gemstone Beryl For about 160 years, beryllium was also known as glucinium (with the accompanying chemical symbol Gl), the name coming from the Greek word for sweet due to the sweet taste of its salts. A bivalent element, beryllium is found in nature as a combination with other elements in minerals. Notable gemstones which contain beryllium include Beryl (Aquamarine, Emerald) and Crysoberyl. The free element is a steelgray, strong, lightweight, brittle, alkaline earth metal with an atomic weight of 9.01218 g/mol. It is primarily used as a hardening agent in alloys, notably beryllium copper. Structurally, beryllium s very low density (1.85 times that of water), high melting point (1278°C), high temperature stability, and low coefficient of thermal expansion, make it in many ways an ideal aerospace material, and it has been used in rocket nozzles and is a significant component of future-planned space telescopes. Because of its relatively high transparency to X-rays and other ionizing radiation types, beryllium metal also has a number of uses as filters and windows for radiation and particle physics experiments. Commercial use of beryllium metal presents technical challenges due to the toxicity (especially by inhalation) of beryllium-containing dusts. Beryllium produces a direct corrosive effect to human tissue, and can cause a chronic life-threatening allergic disease called Berylliosis in susceptible persons.
Beryllium is a relatively rare element in both the Earth and the Universe because it is not formed in conventional stellar nucleosynthesis. It more accurately was formed during the “Big Bang”, and later from the action of cosmic rays on interstellar dust.
Physikalische Eigenschaften
As the first element in group 2 (IIA), beryllium has the smallest, lightest, and most stableatoms of the alkali earth metals. Its melting point is 1278° C, its boiling point is 2970°C, andits density is 1.8477 g/cm³. Its color is whitish-gray.
Isotopes
Of beryllium s isotopes, only 9Be is stable andthe others are relatively unstable or rare. It is thus a mono-nuclide element. Cosmogenic ¹⁰Be is produced in the atmosphere by cosmic ray spallation of oxygen and nitrogen. Cosmogenic ¹⁰Be accumulates at the soil surface, where its relatively long half-life (1.51 million years) permits a long residence time before decaying to ⁹Be. Thus, ¹⁰Be and its daughter products have been used to examine soil erosion and soil formation from regolith (which is soil formed by material originating through rock weathering or plant growth), the development of lateritic soils as well as variations in solar activity, and the age of ice cores. Solar activity is inversely correlated with ¹⁰Be production, because the solar wind decreases the flux of galactic cosmic rays which reach the Earth. Beryllium-10 is also formed in nuclear explosions by a reaction of fast neutrons with 13C in the carbon dioxide in air, and is one of the historical indicators of past activity at nuclear test sites.
The fact that ⁷Be and ⁸Be are unstable has profound cosmological consequences as it means that elements heavier than beryllium could not have been produced by nuclear fusion in the “Big Bang” since there was insufficient time during the nucleosynthesis phase of the Big Bang expansion to produce carbon by fusion of ⁴He nuclei. The other factor was the relatively low concentrations of ⁸Be available because of its short half-life. Astronomer Fred Hoyle first showed that the energy levels of ⁸Be and ¹²C allow carbon production by a triple-alpha process in helium-fueled stars where more synthesis timeis available. ⁷Be decays by electron capture. Therefore, its decay rate is dependent upon its electron configurationda rare occurrence in nuclear decay. The shortest-lived known isotope of beryllium is ¹³Be which decays through neutron emission. It has a half-life of 2.7×10²¹s. ⁶Be is also very short lived with a halflife of 4.96×10²¹s. The exotic isotopes ¹¹Be and ¹⁴Be are known to exhibit a “nuclear halo”.
Origin of Name
Beryllium was originally known as “glucina” (glucose) from the Greek word glukos, meaning “sugar,” because of the sweet taste of a few of its salt compounds. Later, beryllium was given the Greek name beryllos after the greenish-blue gemstone beryl (emeralds) that was later found to contain the element beryllium.
Occurrence
Since its discovery, beryllium has been classed as the 36th most abundant of the elementsfound in the Earth’s crust. Beryllium’s principle source is a mineral composed of a complex ofberyllium, silicon, and oxygen. It is usually found in deposits as hexagonal crystalline formsin Brazil, Argentina, South Africa, and India as well as in Colorado, Maine, New Hampshire,and South Dakota in the United States. Some deposits have been found in Canada. Manycrystals of the mineral may be very large One chunk that measured 27 feet long length andweighed a 25 tons was found in Albany, Maine in 1969.One method of obtaining beryllium metal is by chemical reduction, whereby berylliumoxide is treated with ammonium fluoride and some other heavy metals to remove impuritieswhile yielding beryllium fluoride. This beryllium fluoride is then reduced at high temperaturesusing magnesium as a catalyst, which results in deposits of “pebbles” of metallic beryllium.Another method for obtaining beryllium metal is by electrolysis of a solution of berylliumchloride (BeCl₂) along with NaCl as an electrolyte in solution that is kept molten but belowthe melting point of beryllium. (₄Be has a relatively high melting point of 2,332.4°F.) Theberyllium metal does not collect at the negative cathode as do metals in other electrolyticcells, but rather beryllium metal pieces are found at the bottom of the cell at the end of theprocess.
Charakteristisch
Beryllium is one-third as dense as aluminum. Fresh-cut surfaces of the metal oxidize,thus resisting further oxidation, as does aluminum. It is a lightweight, hard, brittle metal. Itcan be machined (rolled, stretched, and pounded) into many shapes and is used to producelightweight alloys.
History
Beryllium was discovered as the oxide by Vauquelin in beryl and in emeralds in 1798. The metal was isolated in 1828 by Wohler and by Bussy independently by the action of potassium on beryllium chloride. Beryllium is found in some 30 mineral species, the most important of which are bertrandite, beryl, chrysoberyl, and phenacite. Aquamarine and emerald are precious forms of beryl. Beryllium minerals are found in the U.S., Brazil, Russia, Kazakhstan, and elsewhere. Colombia is known for its emeralds. Beryl (3BeO · Al2O3 · 6SiO2) and bertrandite (4BeO · 2SiO2 · H2O) are the most important commercial sources of the element and its compounds. Most of the metal is now prepared by reducing beryllium fluoride with magnesium metal. Beryllium metal did not become readily available to industry until 1957. The metal, steel gray in color, has many desirable properties. It is one of the lightest of all metals, and has one of the highest melting points of the light metals. Its modulus of elasticity is about one third greater than that of steel. It resists attack by concentrated nitric acid, has excellent thermal conductivity, and is nonmagnetic. It has a high permeability to X-rays, and when bombarded by alpha particles, as from radium or polonium, neutrons are produced in the ratio of about 30 neutrons/million alpha particles. At ordinary temperatures beryllium resists oxidation in air, although its ability to scratch glass is probably due to the formation of a thin layer of the oxide. Beryllium is used as an alloying agent in producing beryllium copper, which is extensively used for springs, electrical contacts, spot-welding electrodes, and nonsparking tools. It has found application as a structural material for high-speed aircraft, missiles, spacecraft, and communication satellites. It is being used in the windshield frame, brake discs, support beams, and other structural components of the space shuttle. Because beryllium is relatively transparent to X-rays, ultra-thin Be-foil is finding use in X-ray lithography for reproduction of microminiature integrated circuits. Natural beryllium is made of 9Be and is stable. Eight other radioactive isotopes are known.
Beryllium is used in nuclear reactors as a reflector or moderator for it has a low thermal neutron absorption cross section. It is used in gyroscopes, computer parts, and instruments where lightness, stiffness, and dimensional stability are required. The oxide has a very high melting point and is also used in nuclear work and ceramic applications. Beryllium and its salts are toxic and should be handled with the greatest of care. Beryllium and its compounds should not be tasted to verify the sweetish nature of beryllium (as did early experimenters). The metal, its alloys, and its salts can be handled safely if certain work codes are observed, but no attempt should be made to work with beryllium before becoming familiar with proper safeguards. Beryllium metal is available at a cost of about $5/g (99.5% pure).
Verwenden
In the mid-twentieth century, the determination that beryllium has a number of uniqueproperties led to the production of beryllium metal by electrolysis on a commercial scale. Itproved valuable as an alloy metal to produce specialized, strong—but light—structural metalsfor use in satellites, aircraft, and spacecraft.A 2% beryllium mixture with copper produces a unique alloy of bronze that is six timesstronger than copper metal. This alloy does not give off sparks when struck with a hammer—avaluable characteristic when metals must be used in explosive gaseous environments. This alloysometimes contains small amounts of other metals such as nickel or cobalt, which makes forexcellent electrical conductivity for switching equipment, given the alloy’s simultaneous hardness and nonsparking qualities. Beryllium is also “transparent” to X-rays, which makes it idealfor windows for X-ray tubes.In 1932 James Chadwick (1891–1974) bombarded beryllium with alpha particles (heliumnuclei) that produced free neutrons. Since then, this nuclear process has made beryllium areliable neutron emitter for laboratory nuclear research. Beryllium is not only an excellentmoderator to slow down high-speed neutrons in nuclear reactors, but it also can act as areflector of neutrons as well.Beryllium is an excellent source of alpha particles, which are the nuclei of helium atoms.Alpha particles (radiation) are not very penetrating. These particles travel only a few inchesin air and can be stopped by a sheet of cardboard. Alpha particles are produced in cyclotrons(atom smashers) and are used to bombard the nuclei of other elements to study their characteristics.In the first part of the twentieth century, beryllium was used as coating inside fluorescentelectric light tubes, but proved carcinogenic (causes cancer) when broken tubes producedberyllium dust that was inhaled. Because of this potential to cause cancer, since 1949 beryllium has no longer been used as the inside coating of fluorescent tubes. Beryllium is alsoused for computer parts, electrical instrument components, and solid propellant rocket fuels.Because it is one of the few metals that is transparent to X-rays, it is used to make special glassfor X-ray equipment.
Verwenden
Beryllium metal sheet or wire; ceramics; hardening agent in alloys used especially in the electronics field
Verwenden
Source of neutrons when bombarded with alpha particles according to the equation 94Be + 42He 612C + 10n. This yields about 30 neutrons per million alpha particles. Also as neutron reflector and neutron moderator in nuclear reactors. In beryllium copper and beryllium aluminum alloys (by direct reduction of beryllium oxide with carbon in the presence of Cu or Al). In aerospace, aircraft and satellite structures; x-ray transmission windows; missile parts; nuclear weapons; fuel containers; precision instruments; rocket propellants; navigational systems; heat shields; and mirrors. For fiber optics and cellular network communications systems.
Definition
Only the surface is oxidized in air. Hydride is not formed. Nitride is formed by reacting with N2 and NH3. An oxide film is formed only on the surface and it is not changed further. It dissolves into HCl and H2SO4, generating hydrogen, but it does not react with HNO3.
Definition
A light metallic element, similar to aluminum but somewhat harder; the first element in group 2 (formerly IIA) of the periodic table. It has the electronic configuration of helium with two additional outer 2s electrons.
Beryllium occurs in a number of minerals such as beryllonite (NaBePO₄), chrysoberyl (Be(AlO₂)₂), bertrandite (4BeO·2SiO₂), and beryl (3BeO·Al₂O₃·6SiO₂). The element accounts for only 0.0006% by mass of the Earth’s crust. The metal is obtained by conversion of the ore to the sulfate at high temperature and pressure with concentrated sulfuric acid, then to the chloride, followed by electrolysis of the fused chloride. Alternatively, extraction by hydrogen fluoride followed by electrolysis of the fused fluoride may be employed. The metal has a much lower general reactivity than lithium or other elements in group 2. It is used as an antioxidant and hardener in some alloys, such as copper and phosphor bronzes. Beryllium has the highest ionization potential of group 2 and the smallest size. Consequently it is less electropositive and more polarizing than other members of the group. Thus, Be2+ ions do not exist as such in either solids or solutions, and even with the most electronegative elements there is partial covalent character in the bonds. The metal reacts directly with oxygen, nitrogen, sulfur, and the halogens at various elevated temperatures, to form the oxide BeO, nitride Be3N2, sulfide BeS, and halides BeX₂, all of which are covalent. Beryllium does not react directly with hydrogen but a polymeric hydride (BeH2)n can be prepared by reduction of (CH₃)₂Be using lithium tetrahydridoaluminate. Beryllium is amphoteric forming beryllate species, such as [Be(OH)₄]^2– and [Be(OH)]₃ ³⁺. The hydroxide is only weakly basic. The element does not form a true carbonate; the basic beryllium carbonate, BeCO₃.Be(OH)₂ is formed when sodium carbonate is added to solutions of beryllium compounds.
Beryllium hydride, chloride, and dimethylberyllium form polymeric bridged species but, whereas the bridging in the chloride is via an electron pair on chlorine atoms and can be regarded as an electronpair donor bond, the bonding in the hydride and in the methyl compound involves two-electron three-centre bonds. Coordination compounds are quite common with beryllium; some examples include [BeCl₄]^2–, (R2O)₂BeCl₂, and [Be(NH₃)₄]Cl₂. Beryllium also forms a number of alkyl compounds, some of which can be stabilized by coordination. Beryllium is extremely toxic.
Definition
ChEBI: Alkaline earth metal atom with atomic number 4.
Definition
beryllium: Symbol Be. A grey metallicelement of group 2 (formerly IIA)of the periodic table; a.n. 4; r.a.m.9.012; r.d. 1.85; m.p. 1278°C; b.p.2970°C. Beryllium occurs as beryl(3BeO.Al₂O₃.6SiO₂) and chrysoberyl(BeO.Al₂O₃). The metal is extractedfrom a fused mixture of BeF₂/NaF byelectrolysis or by magnesium reductionof BeF₂. It is used to manufactureBe–Cu alloys, which are used innuclear reactors as reflectors andmoderators because of their low absorptioncross section. Berylliumoxide is used in ceramics and in nuclearreactors. Beryllium and its compoundsare toxic and can causeserious lung diseases and dermatitis.The metal is resistant to oxidation byair because of the formation of anoxide layer, but will react with dilutehydrochloric and sulphuric acids.Beryllium compounds show high covalentcharacter. The element wasisolated independently by F. W?hlerand A. A. Bussy in 1828.
Vorbereitung Methode
Metallic beryllium is produced by reduction of beryllium halide with sodium, potassium or magnesium. Commercially, it is obtained primarily from its ore, beryl. Beryllium oxide is separated from silica and alumina in ore by melting the ore, quenching the solid solution, and solubilizing in sulfuric acid at high temperatures and pressure. Silica and alumina are removed by pH adjustment. Beryllium is converted to its hydroxide. Alternatively, beryl is roasted with complex fluoride. The products are dissolved in water and then pH is adjusted to produce beryllium hydroxide.
The impure hydroxide obtained above is purified by converting to a double salt, ammonium beryllium fluoride, which subsequently, on thermal decomposition, gives beryllium fluoride. The latter is heated with magnesium metal BERYLLIUM 97 to form pure beryllium metal:
BeF +Mg→Be + MgF2
It finally is purified by either vacuum melting or chelation with an organophosphate reagent followed by liquid-liquid extraction. Beryllium halide alternatively may be reduced to the metal or converted to alloy by electrolysis.
Reaktionen
Most chemical reactions of beryllium are similar to those of aluminum and, to a lesser extent, magnesium. In general, all the common mineral acids attack beryllium forming their corresponding salts with evolution of hydrogen:
Be + 2HCl → BeCl2 + H2
Cold, concentrated nitric acid, however, has no effect when mixed with the metal.
Reactions with alkalies first produce insoluble beryllium hydroxide with evolution of hydrogen. Excess alkali converts the hydroxide to water-soluble beryllate:
Be(OH)2 + 2NaOH → Na2BeO2 + H2O
Beryllium does not react with oxygen at ordinary temperatures and normal atmosphere. When heated above 700°C, the metal combines with nitrogen, (in an oxygen-free atmosphere) forming beryllium nitride, Be3N2.
Beryllium combines with carbon when heated above 900°C in the absence of air to form beryllium carbide.
2Be + 2C→（>900℃）→Be2C
Beryllium reacts incandescently with fluorine or chlorine, producing beryllium fluoride or chloride.
Allgemeine Beschreibung
A grayish-white hard light metal. Denser than water, but the powder may float. May be toxic by inhalation. Will burn if involved in a fire.
Air & Water Reaktionen
Highly flammable. Insoluble in water.
Reaktivität anzeigen
Boron trifluoride reacts with incandescence when heated with alkali metals or alkaline earth metals except magnesium [Merck 11th ed. 1989]. Finely divided or amalgamated metal reacts with HCl, dil HNO3, or dil H2SO4; attacked by strong base with evolution of hydrogen gas [Merck 11th ed. 1989]. BERYLLIUM has been determined experimentally that a mixture of BERYLLIUM with carbon tetrachloride or with trichloroethylene will flash or spark on heavy impact [ASESB Pot. Incid. 39 1968]. The reaction between beryllium and the vapors of phosphorus proceeds with incandescence [Mellor 8:842 1946-47].
Hazard
The elemental metallic form of beryllium is highly toxic, as are most of its compounds.When inhaled, the fumes, dust, or particles of beryllium are highly carcinogenic. Some berylliumcompounds are toxic when they penetrate cuts in the skin (e.g., when an old fluorescenttube breaks). Beryllium oxide when inhaled can result in a fatal disease known as berylliosis(similar to, but more toxic than, silicosis).
As with many other chemicals, beryllium has its positives and negatives. Although it is animportant industrial chemical, the handling of beryllium is best left to experienced workersand laboratory personnel in proper facilities.
Health Hazard
Beryllium and its compounds are highly toxic substances. Beryllium can affect all organ systems, although the primary organ involved is the lung. Beryllium causes systemic disease by inhalation and can distribute itself widely throughout the body after absorption from the lungs. The signs and symptoms of chronic beryllium poisoning include, cough, chest pain, fatigue, dyspnea, anorexia, cyanosis, cubbing, hepatomegaly, splenomegaly with complications of cardiac failure, renal stone, and pneumothorax. Little beryllium is absorbed from the gastrointestinal tract. Beryllium can cause skin irritation and its traumatic introduction into subcutaneous tissue can cause local irritation and granuloma formation. Beryllium is a potent inhibitor of various enzymes of phosphate metabolism, particularly of alkaline phosphatase. The health hazards of beryllium are almost exclusively confi ned to inhalation exposure and skin contactBeryllium and its salts are toxic and should be handled with the greatest of care. Beryllium and its compounds should not be tasted to verify its sweetish nature. Ingestion and breathing of beryllium is harmful. Acute exposures to high levels of beryllium cause mild infl ammation of the nasal mucous membranes and pharynx, rhinitis and pharyngitis, tracheo-bronchitis, and pneumonitis. The symptoms of acute pneumonitis are cough, respiratory distress, substernal discomfort or pain, loss of appetite, weakness, tiredness, chest pain, and cyanosis.Beryllium can be very harmful when humans breathe it in, because it can damage the lungs and cause pneumonia. The most commonly known effect of beryllium is called berylliosis, a dangerous and persistent lung disorder that can also damage other organs, such as the heart. In about 20% of all cases, people die of this disease. Breathing in beryllium in the workplace causes berylliosis. People that have weakened immune systems are most susceptible to this disease. Beryllium can also cause allergic reactions with people that are hypersensitive to this chemical and cause chronic beryllium disease (CBD). The symptoms are weakness, tiredness, and breathing problems. Some people that suffer from CBD will develop anorexia and blueness of hands and feet. Sometimes, people can even be in such a serious condition that CBD can cause their death. Next to causing berylliosis and CBD, beryllium can also increase the chances of developing cancer and DNA damage. Chronic beryllium disease is a pulmonary and systemic granulomatous disease caused by inhalation of beryllium. The latency of the disease can be from 1 to 30 years, most commonly occurring 10–15 years after fi rst exposure. From the reported use pattern of beryllium, it can be deduced that toxicologically relevant exposure to beryllium is largelyconfi ned to the workplace. Only a few exposure situations have been reported for the general population
Industrielle Verwendung
Among structural metals, beryllium (symbolBe) has a unique combination of properties. Ithas low density (two thirds that of aluminum),high modulus per weight (five times that ofultrastrength steels), high specific heat, highstrength per density, excellent dimensionalstability, and transparency to x-rays. Berylliumis expensive, however, and its impactstrength is low compared to values for mostother metals.
Beryllium is a steel-gray lightweight metal,used mainly for its excellent physical propertiesrather than its mechanical properties. Except formagnesium (Mg), it is the lightest in weight ofcommon metals, with a density of 1855 kg/m3.It also has the highest specific heat (1833J/kg K) and a melting point of 1290°C. It isnonmagnetic, has about 40% the electrical conductivityof copper, a thermal conductivity of190 W/m K, high permeability to x-rays, andthe lowest neutron cross section of any metalhaving a melting point above 500°C.
mögliche Exposition
Beryllium is used extensively in manufacturing electrical components, chemicals, ceramics, nuclear reactors; in the aerospace industry; and X-ray tubes. Beryllium and Compounds 423 A number of alloys are produced in which beryllium is added to yield greater tensile strength, electrical conductivity, and resistance to corrosion and fatigue. The metal is used as a neutron reflector in high-flux test reactors. Human exposure occurs mainly through inhalation of beryllium dust or fumes by beryllium ore miners, beryllium alloy makers and fabricators; phosphor manufacturers; ceramic workers; missile technicians; nuclear reactor workers; electric and electronic equipment workers; and jewelers. The major source of beryllium exposure of the general population is thought to be the burning of coal. Approximately 250,000 pounds of beryllium is released from coal and oil-fired burners. EPA estimates the total release of beryllium to the atmosphere from point sources is approximately 5500 pounds per year. The principal emissions are from beryllium copper alloy production. Approximately 721,000 persons living within 12.5 mi (20 km) of point sources are exposed to small amounts of beryllium (median concentration 0.005 μ/m3). Levels of beryllium have been reported in drinking water supplies and in small amounts in food.
Erste Hilfe
If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Seek medical attention immediately. Ifthis chemical has been inhaled, remove from exposure,begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medical attention. Give large quantities of water and inducevomiting. Do not make an unconscious person vomit.
Carcinogenicity
Beryllium and beryllium compounds are known to be human carcinogens based on sufficient evidence of carcinogenicity from studies in humans. Beryllium and beryllium compounds were first listed in the Second Annual Report on Carcinogens as reasonably anticipated to be human carcinogens based on sufficient evidence of carcinogenicity from studies in experimental animals. The listing was revised to known to be human carcinogens in the Tenth Report on Carcinogens in 2002.
Environmental Fate
Beryllium compromises the immune system. Enzymes catalyzed by magnesium or calcium can be inhibited by beryllium; succinic dehydrogenase is activated. Beryllium exposure leads to a deficiency in lung carbon monoxide diffusing capacity. Hypercalcemia (excess of calcium in the blood) can occur.
Because of the toxicity of beryllium vapor and dust, all operations should be carried out in properly ventilated rooms, and with vented equipment. Source exhaust has been found to be most effective. In the presence of poorly controlled high workplace concentrations, finedust masks with filters of the specific safety level must be worn.
Lager
(1) Color Code—Red (powder): FlammabilityHazard: Store in a flammable liquid storage area orapproved cabinet away from ignition sources and corrosiveand reactive materials. (2) Color Code—Blue: HealthHazard/Poison: Store in a secure poison location. Berylliummust be stored to avoid contact with oxidizers (such asperchlorates, peroxides, permanganates, chlorates, andnitrates); and strong acids (such as hydrochloric, sulfuric,and nitric); since violent reactions occur. Store in tightlyclosed containers in a cool, well-ventilated area away fromheat. Protect storage containers from physical damage. Useonly nonsparking tools and equipment, especially whenopening and closing containers of beryllium. A regulated,marked area should be established where this chemicalis handled, used, or stored in compliance with OSHAStandard 1910.1045.
Versand/Shipping
UN1567: Beryllium powder, Hazard class: 6.1; Labels: 6.1—Poisonous material, 4.1—Flammable solid.
Toxicity evaluation
Beryllium enters the environment principally through emissions from the combustion of fossil fuels and ore processing. Average ambient air concentrations in the United States have been measured at 0.03 ng m^-3, whereas median concentration in cities is 0.2 ng m^-3.
Insolubility of beryllium and many of its compounds can lead to long-term persistence in the environment, as particulates suspended in water until deposition in sediment, or in soils. Concentrations of beryllium in soil are found in the United States, as well as, more recently, in Brazil, Argentina, Madagascar, India, and Russia.
Long-range transport of beryllium is common in continental river systems, whereas brackish mixing zones exhibit scavenging. It is not yet known whether beryllium ceases transport in these estuarine waters and deposits in sediments, or continues to the deep ocean, although beryllium concentrations in deep ocean waters around the world are uniform.
Structure and conformation
The space lattice of Beryllium belongs to the hexagonal system, and its close-packed hexagonal lattice has constants of a = 0.228 nm, c = 0.3977 nm (188 ℃).
Inkompatibilitäten
Beryllium metal reacts with strong acids; alkalis (forming combustible hydrogen gas), oxidizable materials. Forms shock sensitive mixtures with some chlorinated solvents, such as carbon tetrachloride and trichloroethylene. Incompatible with caustics, chlorinated hydrocarbons, oxidizers, molten lithium.
Waste disposal
For beryllium (powder), waste should be converted into chemically inert oxides using incineration and particulate collection techniques. These oxides should be returned to suppliers if possible. Recovery and recycling is an alternative to disposal for beryllium scrap and pickle liquors containing beryllium.

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