Analysis method
The quantitative determination of beryllium, even in very small amounts, is especially important because of the toxicity of beryllium. The best method is atomic absorption spectrometry.When an acetylene/nitrous oxide flame is used, even beryllium oxide is excited, and it is possible to analyze any solution or dispersion without preliminary treatment. Other methods have also been described.
Description
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.
Chemical Properties
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).
Chemical Properties
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.
Chemical Properties
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.
Physical properties
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/cm
3. Its color is whitish-gray.
Physical properties
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.
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 2.7×10
21s.
6Be is also very short lived with a halflife
of 4.96×10
21s. 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 (BeCl
2) 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.
Characteristics
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).
Uses
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.
Uses
Beryllium metal sheet or wire; ceramics;
hardening agent in alloys used especially in
the electronics field
Uses
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.
Production Methods
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.
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 (NaBePO
4), chrysoberyl (Be(AlO
2)
2), bertrandite (4BeO·2SiO
2), and beryl (3BeO·Al
2O
3·6SiO
2). 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 BeX
2, all of which are covalent. Beryllium does not react directly with hydrogen but a polymeric hydride (BeH2)n can be prepared by reduction of (CH
3)
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, BeCO
3.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 [BeCl
4]
2–, (R2O)
2BeCl
2, and [Be(NH
3)
4]Cl
2. 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.Al
2O
3.6SiO
2) and chrysoberyl(BeO.Al
2O
3). The metal is extractedfrom a fused mixture of BeF
2/NaF byelectrolysis or by magnesium reductionof BeF
2. 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.
Reactions
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.
General Description
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 Reactions
Highly flammable. Insoluble in water.
Reactivity Profile
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
Industrial uses
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.
Potential Exposure
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.
First aid
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.
storage
(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.
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 ℃).
Incompatibilities
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.
