Difference between revisions of "Beryllium" - New World Encyclopedia

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{{Elementbox_header | number=4 | symbol=Be | name=beryllium | left=[[lithium]] | right=[[boron]] | above=- | below=[[magnesium|Mg]] | color1=#ffdead | color2=black }}
 
{{Elementbox_header | number=4 | symbol=Be | name=beryllium | left=[[lithium]] | right=[[boron]] | above=- | below=[[magnesium|Mg]] | color1=#ffdead | color2=black }}
 
{{Elementbox_series | [[alkaline earth metal]]s }}
 
{{Elementbox_series | [[alkaline earth metal]]s }}
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'''Beryllium''' (chemical symbol '''Be''', [[atomic number]]* 4) ranks among the lightest of all known [[metal]]s. Steel-gray in color, it is strong but brittle and is classified as an [[alkaline earth metal]].
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'''Beryllium''' (chemical symbol '''Be''', [[atomic number]] 4) ranks among the lightest of all known [[metal]]s. Steel-gray in [[color]], it is strong but brittle. It is classified as an [[alkaline earth metal]], along with [[calcium]] and [[magnesium]]. Precious forms of its mineral [[beryl]] are [[aquamarine]] and [[emerald]]. This metal, its [[alloy]]s, and compounds are toxic and need to be handled with care. One needs to especially avoid inhaling their dust and vapors.
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[[Alloy]]s of beryllium with [[copper]] or [[nickel]] are strong and wear-resistant, and are widely used in the manufacture of such items as computer parts, gyroscopes, electrodes, springs, and nonsparking tools. In addition, its alloys are useful as lightweight structural materials for high-speed [[aircraft]], [[missile]]s, [[spacecraft]], and [[satellite]]s. The nuclear power industry uses beryllium in [[nuclear reactor]]s as a neutron reflector and moderator. In X-ray lithography, beryllium is used for the reproduction of microscopic [[integrated circuit]]s. [[Beryllium oxide]] is useful for applications that require an excellent heat conductor and electrical insulator, with a very high [[melting point]] and high strength and hardness.
  
* A  [[Bivalent (chemistry)|bivalent]] element
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== Occurrence and production ==
* primarily used as a hardening agent in [[alloy]]s (most notably [[beryllium copper]]).
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[[Image:Beryllium_OreUSGOV.jpg|thumb|left|Beryllium ore]]
  
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Beryllium is a significant constituent of about 100 [[mineral]]s. The most important of these are [[beryl]] (Al<sub>2</sub>Be<sub>3</sub>Si<sub>6</sub>O<sub>18</sub>), [[bertrandite]] (Be<sub>4</sub>Si<sub>2</sub>O<sub>7</sub>(OH)<sub>2</sub>), [[chrysoberyl]] (Al<sub>2</sub>BeO<sub>4</sub>), and [[phenakite]] (Be<sub>2</sub>SiO<sub>4</sub>). Precious forms of beryl are [[aquamarine]] and [[emerald]].
  
From USGS:
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The main commercial sources of beryllium and its compounds are beryl and bertrandite. Beryllium metal did not become readily available until 1957. Currently, the chief method of production is by reducing [[beryllium fluoride]] with [[magnesium]] metal. The [[chemical reaction]] can be written in terms of the following equation.
"Beryllium (Be) is one of the lightest of all metals and has one of the highest melting points of any light metal.  Beryllium metal is used principally in aerospace and defense applications because of its stiffness, light weight, and dimensional stability over a wide temperature range.  Beryllium-copper alloys are used in a wide variety of applications because of their electrical and thermal conductivity, high strength and hardness, good corrosion and fatigue resistance, and nonmagnetic properties.  Beryllium oxide is an excellent heat conductor, with high strength and hardness, and acts as an electrical insulator in some applications.  The United States, one of only three countries that process beryllium ores and concentrates into beryllium products, supplies most of the rest of the world with these products."
 
 
 
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== Occurrence ==
 
 
 
Beryllium is a significant constituent of about 100 [[mineral]]s. The most important of these are [[beryl]]* (Al<sub>2</sub>Be<sub>3</sub>Si<sub>6</sub>O<sub>18</sub>), [[bertrandite]]* (Be<sub>4</sub>Si<sub>2</sub>O<sub>7</sub>(OH)<sub>2</sub>), [[chrysoberyl]]* (Al<sub>2</sub>BeO<sub>4</sub>), and [[phenakite]]* (Be<sub>2</sub>SiO<sub>4</sub>). Precious forms of beryl are [[aquamarine]]* and [[emerald]].
 
 
 
The main commercial sources of beryllium and its compounds are beryl and bertrandite. Beryllium metal did not become readily available until 1957. Currently, the chief method of production is by reducing [[beryllium fluoride]]* with [[magnesium]] metal. The chemical reaction can be written in terms of the following equation.
 
  
 
:BeF<sub>2</sub> + Mg → MgF<sub>2</sub> + Be
 
:BeF<sub>2</sub> + Mg → MgF<sub>2</sub> + Be
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== Etymology and Discovery ==
 
== Etymology and Discovery ==
  
The name beryllium comes from the [[Greek language|Greek]] word ''beryllos'', for "beryl." That, in turn, can be traced back to the [[Prakrit]]* ''veruliya'', from [[Pāli]] ''veuriya''. These words appear akin to the [[Tamil language|Tamil]]* ''veliru'' or ''vilar'', meaning "to whiten, become pale."<ref>http://www.bartleby.com/61/74/B0207400.html</ref> At one time, beryllium was referred to as '''glucinium''' (from the [[Greek language|Greek]] word ''glykys'', meaning "sweet"), based on the sweet taste of its [[salt]]s.
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The name beryllium comes from the [[Greek language|Greek]] word ''beryllos'', for "beryl." That, in turn, can be traced back to the [[Prakrit]] ''veruliya'', from [[Pāli]] ''veuriya''. These words appear akin to the [[Tamil language|Tamil]] ''veliru'' or ''vilar'', meaning "to whiten, become pale."<ref>[http://www.bartleby.com/61/74/B0207400.html American Heritage Dictionary, fourth edition, 2000] Retrieved January 30, 2008.</ref> At one time, beryllium was referred to as ''glucinium'' (from the Greek word ''glykys'', meaning "sweet"), based on the sweet taste of its [[salt]]s.
  
Beryllium was discovered by [[Louis Vauquelin]]* in 1798, as the oxide in [[beryl]]* and [[emerald]]s. In 1828, [[Friedrich Woehler|Friedrich Wöhler]]* and [[Antoine Bussy]]* independently isolated the metal by reacting [[potassium]] with [[beryllium chloride]]*.
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Beryllium was discovered by [[Louis Vauquelin]] in 1798, as the oxide in [[beryl]] and [[emerald]]s. In 1828, [[Friedrich Woehler|Friedrich Wöhler]] and [[Antoine Bussy]] independently isolated the metal by reacting [[potassium]] with [[beryllium chloride]].
  
 
== Notable characteristics ==
 
== Notable characteristics ==
  
Among the light [[metal]]s, beryllium has one of the highest [[melting point]]*s. Its [[modulus of elasticity]]* (measure of its elasticity) is approximately one-third more than that of steel. It is nonmagnetic and an excellent conductor of heat. The speed of [[sound]] in beryllium is about 12,500 meters per second&mdash;greater than that through any other element. Highly permeable to [[X ray]]s, it liberates [[neutron]]s when struck by [[alpha particle]]s, such as from [[radium]] or [[polonium]].
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Beryllium is a member of the family of [[alkaline earth metal]]s and lies at the top of group two (former group 2A) of the [[periodic table]], just above [[magnesium]]. In addition, it is situated in period two, between [[lithium]] and [[boron]]. Among the light [[metal]]s, beryllium has one of the highest [[melting point]]s. Its [[modulus of elasticity]] (a measure of its elasticity) is approximately one-third more than that of steel. It is nonmagnetic and an excellent conductor of heat. The speed of [[sound]] in beryllium is about 12,500 meters per second&mdash;greater than that through any other element. Highly permeable to [[X-ray]]s, it liberates [[neutron]]s when struck by [[alpha particle]]s.
  
Beryllium resists attack by concentrated [[nitric acid]]. In addition, at [[standard temperature and pressure]]* (0&deg;C, 100 kPa), it resists [[oxidation]] when exposed to air. It appears, however, that its ability to scratch glass may be due to the formation of a thin layer of its oxide.
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Beryllium resists attack by concentrated [[nitric acid]]. In addition, at [[standard temperature and pressure]] (0&deg;C, 100 kPa), it resists [[oxidation]] when exposed to air. It appears, however, that its ability to scratch glass may be due to the formation of a thin layer of its oxide.
  
 
=== Isotopes ===
 
=== Isotopes ===
[[Image:Solar Activity Proxies.png|thumb|right|300px|Plot showing variations in solar activity, including variation in <sup>10</sup>Be concentration.]]
 
  
Beryllium has 10 [[isotope]]s, of which only <sup>9</sup>Be is stable. [[Cosmogenic]] <sup>10</sup>Be is produced in the [[Earth's atmosphere|atmosphere]] by [[cosmic ray]] [[spallation]] of [[oxygen]] and [[nitrogen]]. Because beryllium tends to exist in [[solution]] at [[pH]] levels less than about 5.5 (and most rainwater has a pH less than 5), it will enter into solution and be transported to the Earth's surface via rainwater. As the [[precipitation (chemistry)|precipitation]] quickly becomes more [[alkaline]], beryllium drops out of solution. Cosmogenic <sup>10</sup>Be thereby accumulates at the [[soil]] surface, where its relatively long [[half-life]] (1.51 million years) permits a long residence time before decaying to <sup>10</sup>[[boron|B]]. <sup>10</sup>Be and its daughter products have been used to examine [[soil erosion]], [[soil formation]] from [[regolith]], the development of [[laterite|lateritic soils]], as well as variations in [[solar activity]] and the age of [[ice core]]s.
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Beryllium has ten [[isotope]]s, of which only <sup>9</sup>Be is stable. The isotope <sup>10</sup>Be is produced in the [[Earth's atmosphere|atmosphere]] by the impact of [[cosmic ray]]s on [[oxygen]] and [[nitrogen]]. This beryllium (being soluble in [[water]] at pH below 5.5) readily dissolves in rainwater (which generally has a pH less than five) and is transported to the Earth's surface. As this water quickly becomes more [[alkaline]], <sup>10</sup>Be drops out of solution and accumulates at the [[soil]] surface. Given its [[half-life]] of 1.51 million years, <sup>10</sup>Be has a long residence time before it decays to <sup>10</sup>B (an isotope of [[boron]]). The isotope <sup>10</sup>Be and its daughter products have therefore been used to examine [[soil erosion]], [[soil formation]] from [[regolith]], and the development of [[laterite|lateritic soils]]. It has also been used to check variations in [[solar activity]] and the age of [[ice core]]s.
  
The fact that <sup>7</sup>Be and <sup>8</sup>Be are unstable has profound cosmological consequences as it means that elements heavier than beryllium could not be produced by nuclear fusion in the [[Big Bang]]. Moreover, the nuclear energy levels of <sup>8</sup>Be are such that carbon can be produced within stars, thus making life possible. (See [[triple-alpha process]] and [[Big Bang nucleosynthesis]]).
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The instability of the isotopes <sup>7</sup>Be and <sup>8</sup>Be has profound consequences for cosmological theory. It means that elements heavier than beryllium could not have been produced by nuclear fusion at the time of the [[Big Bang]]. Moreover, the nuclear energy levels of <sup>8</sup>Be are such that carbon can be produced within stars, thus making it possible for the eventual development of living [[organism]]s.
  
The shortest-lived known isotope of beryllium is <sup>13</sup>Be which decays through [[neutron emission]]. It has a half-life of 2.7&nbsp;&times;&nbsp;10<sup>-21</sup> seconds. <sup>6</sup>Be also is also very short-lived with a half-life of 5.0&nbsp;&times;&nbsp;10<sup>-21</sup> seconds.
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The shortest-lived isotope of beryllium is <sup>13</sup>Be, which has a half-life of 2.7&nbsp;&times;&nbsp;10<sup>-21</sup> seconds and decays through [[neutron emission]]. The isotope <sup>6</sup>Be also is also very short-lived, with a half-life of 5.0&nbsp;&times;&nbsp;10<sup>-21</sup> seconds.
  
The exotics <sup>11</sup>Be and <sup>14</sup>Be are known to exhibit a [[nuclear halo]].
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== Applications ==
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[[Image:Be foil square.jpg|thumb|right|350px|A square beryllium foil mounted in a steel case is ready to be used as a window between a vacuum chamber and an X-ray microscope. Beryllium filters out visible light but is highly transparent to X-rays.]]
  
== Applications ==
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* Beryllium-[[copper]] [[alloy]]s (containing about two percent beryllium) are strong, hard, wear-resistant, and good conductors of heat and electricity. They are useful for gyroscopes, computer parts, and instruments requiring such properties.
* Beryllium is used as an [[alloy]]ing agent in the production of beryllium-[[copper]] because of its ability to absorb large amounts of heat. Beryllium-copper alloys are used in a wide variety of applications because of their [[electrical conductivity|electrical]] and [[thermal conductivity]], high strength and [[hardness]], nonmagnetic properties, along with good corrosion and fatigue resistance. These applications include the making of spot-[[welding]] electrodes, [[Spring (device)|springs]], non-sparking tools and [[electrical contact]]s.
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* The alloy with nickel (98 percent [[nickel]], two percent beryllium) is used in the manufacture of spot-welding electrodes, springs, and nonsparking tools.
* Due to their stiffness, light weight, and dimensional stability over a wide temperature range, beryllium-copper alloys are also used in the defense and aerospace industries as light-weight structural materials in high-speed aircraft, missiles, space vehicles and [[communication satellite]]s.
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* In addition, beryllium alloys are used by the defense and aerospace industries in the production of lightweight structural materials for high-speed aircraft, missiles, space vehicles, and communication [[satellite]]s.
* Thin sheets of beryllium foil are used with [[X-ray]] detection diagnostics to filter out visible light and allow only X-rays to be detected.
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* Thin sheets of beryllium foil are used with [[X-ray]] detection diagnostics, as the foil can filter out visible light and allow only X-rays to pass through.
* In the field of X-ray lithography beryllium is used for the reproduction of microscopic [[integrated circuit]]s.
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* In the field of X-ray lithography, beryllium is used for the reproduction of microscopic [[integrated circuit]]s.
* In the [[telecommunications]] industry, Beryllium is made into tools that are used to tune the highly magnetic [[klystron]]s used for high power [[microwave]] transmissions for safety.  
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* In the [[telecommunications]] industry, beryllium is made into tools that can be safely used for tuning the highly magnetic [[klystron]]s (specialized vacuum tubes) employed in high-power [[microwave]] transmissions.
* Because it has a low [[thermal neutron]] absorption cross section, the nuclear power industry uses this metal in [[nuclear reactor]]s as a neutron reflector and moderator.
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* The nuclear power industry uses this metal in [[nuclear reactor]]s as a neutron reflector and moderator.
 
* Beryllium is used in nuclear weapons for similar reasons. For example, the [[critical mass]] of a plutonium sphere is significantly reduced if the plutonium is surrounded by a beryllium shell.
 
* Beryllium is used in nuclear weapons for similar reasons. For example, the [[critical mass]] of a plutonium sphere is significantly reduced if the plutonium is surrounded by a beryllium shell.
* Beryllium is sometimes used in [[neutron source]]s, in which the beryllium is mixed with an alpha emitter such as <sup>210</sup>[[polonium|Po]], <sup>226</sup>[[radium|Ra]], <sup>239</sup>[[plutonium|Pu]] or <sup>241</sup>[[americium|Am]].
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* Beryllium is sometimes used in [[neutron source]]s, in which the beryllium is mixed with an alpha emitter such as <sup>210</sup>[[polonium|Po]], <sup>226</sup>[[radium|Ra]], <sup>239</sup>[[plutonium|Pu]], or <sup>241</sup>[[americium|Am]].
* Beryllium is also used in the making of [[gyroscope]]s, various [[computer]] equipment, watch springs and instruments where light-weight, rigidity and dimensional stability are needed.
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* Beryllium is also used in making [[gyroscope]]s and various [[computer]] components, where lightweight materials with rigidity and dimensional stability are needed.
* [[Beryllium oxide]] is useful for many applications that require an excellent heat conductor, with high strength and hardness, with a very high melting point, and that acts as an electrical insulator.
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* Beryllium is being used in the [[Joint European Torus]] fusion research facility, to condition the plasma-facing components
* Beryllium compounds were once used in [[fluorescent light]]ing tubes, but this use was discontinued because of [[berylliosis]] in the workers manufacturing the tubes (see below).
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* [[Beryllium oxide]] is useful for applications that require an excellent heat conductor and electrical insulator, with a very high [[melting point]] and high strength and hardness.
* The [[James Webb Space Telescope]]<ref>[http://www.jwst.nasa.gov/Telescope/mirrortale/ Beryllium related details from NASA]</ref> will have 18 hexagonal beryllium sections for its mirrors.  Because JWST will face a temperature of &minus;240 degrees Celsius (30 kelvins), the mirror is made of beryllium, a material capable of handling extreme cold better than glass. Beryllium contracts and deforms less than glass &mdash; and thus remains more uniform &mdash; in such temperatures.
 
* Beryllium is also used in the [[Joint European Torus]] fusion research facility, to condition the plasma facing components.<ref>http://www.jet.efda.org/pages/focus/011fusion-tech/index.html#investigations</ref>
 
* Beryllium has also been used in [[tweeter]] construction by the company [[Focal-JMlab]] on its flagship Utopia Be series as an alternative to [[titanium]] and [[aluminium]], largely due to its lower density and greater rigidity.<ref>http://www.focal.tm.fr/accueil_en.htm</ref>
 
 
 
''See also [[:category:Beryllium compounds|Beryllium compounds]]''.
 
  
 
==Health effects==
 
==Health effects==
===Precautions ===
 
[[Image:Beryllium_OreUSGOV.jpg|thumb|Beryllium ore]]
 
Beryllium and its salts are [[toxic]] substances and potentially [[carcinogen]]ic. Chronic [[berylliosis]] is a [[pulmonary]] and [[systemic]] [[granulomatous]] disease caused by exposure to beryllium. Acute beryllium disease in the form of [[chemical pneumonitis]] was first reported in Europe in 1933 and in the United States in 1943. Cases of chronic berylliosis were first described in 1946 among workers in plants manufacturing [[fluorescent lamp]]s in [[Massachusetts]]. Chronic berylliosis resembles [[sarcoidosis]] in many respects, and the differential diagnosis is often difficult.
 
  
Although the use of beryllium compounds in fluorescent lighting tubes was discontinued in 1949, potential for exposure to beryllium exists in the nuclear and aerospace industries and in the refining of beryllium metal and melting of beryllium-containing alloys, the manufacturing of electronic devices, and the handling of other beryllium-containing material.
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Beryllium, its [[alloy]]s, and its [[salt]]s are [[toxic]], and one should especially avoid inhaling their dust and fumes. Exposure to these materials can lead to two types of conditions: acute beryllium disease (acute berylliosis) and chronic beryllium disease (chronic berylliosis).<ref>[http://www.ccohs.ca/oshanswers/diseases/beryllium.html Canadian Centre for Occupational Health and Safety: Beryllium Disease] Retrieved January 30, 2008.</ref> In addition, long-term exposure can increase the risk of developing lung cancer.
  
Early researchers tasted beryllium and its various compounds for sweetness in order to verify its presence. Modern diagnostic equipment no longer necessitates this highly risky procedure and no attempt should be made to ingest this substance. Beryllium and its compounds should be handled with great care and special precautions must be taken when carrying out any activity which could result in the release of beryllium dust ([[lung cancer]] is a possible result of prolonged exposure to beryllium laden dust).
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An acute condition is that which develops after a short, heavy exposure and lasts for no more than a year. Depending on the type of exposure, acute beryllium disease may involve inflammation of the skin (contact dermatitis), nose and throat (nasopharyngitis), windpipe (tracheobronchitis), or lungs (pneumonitis).
  
This substance can be handled safely if certain procedures are followed. No attempt should be made to work with beryllium before familiarization with correct handling procedures.
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Chronic beryllium disease develops after prolonged (months or years) of exposure to beryllium. The time lapse between first exposure and symptoms of the disease may be as much as ten to 15 years. The chronic disease affects mainly the lungs but its effects may also be seen in other organs. The condition produces lesions and granulomas (tissue masses) mainly in the [[lung]]s, but it may also affect other [[organ]]s, such as the [[skin]], [[liver]], [[kidney]], [[heart]], [[bone]], [[lymphatic system]], and [[nervous system]]. Symptoms of the chronic disease include coughing, chest pain, and breathing difficulties.
  
A successful test for beryllium on different surface areas has been recently developed. The procedure uses fluorescence when beryllium is bound to sulfonated hydroxybenzoquinoline to detect up to 10 times lower than the recommended limit for beryllium concentration in the work place.  Fluorescence increases with increasing beryllium concentration.  The new procedure has been successfully tested on a variety of surfaces.
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Acute chemical pneumonitis was first reported in [[Europe]] in 1933 and in the [[United States]] in 1943. Cases of chronic berylliosis were first described in 1946 among workers in plants manufacturing [[fluorescent lamp]]s in [[Massachusetts]], and the use of beryllium compounds in fluorescent lighting tubes was discontinued in 1949. The potential for exposure to beryllium exists in the nuclear and aerospace industries, the refining of beryllium metal, melting of beryllium-containing alloys, the manufacture of electronic devices, and the handling of other beryllium-containing materials.
  
=== Inhalation ===
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Early researchers tasted beryllium and its various compounds for sweetness, to verify its presence. Modern diagnostic equipment no longer necessitates this highly risky procedure, and no attempt should be made to ingest this substance. Beryllium and its compounds should be handled with great care, and special precautions must be taken when carrying out any activity that may involve the release of beryllium dust. No attempt should be made to work with beryllium before familiarization with correct handling procedures.
  
Beryllium can be harmful if inhaled and the effects depend on period of exposure. If beryllium air levels are high enough (greater than 100 µg/m³), an acute condition can result, called acute beryllium disease, which resembles pneumonia. Occupational and community air standards are effective in preventing most acute lung damage.  Long term exposure to beryllium can increase the risk of developing lung cancer. The more common and serious health hazard from beryllium today is chronic beryllium disease (CBD), discussed below. It continues to occur in industries as diverse as metal recycling, dental laboratories, alloy manufacturing, nuclear weapons production, defense industries, and metal machine shops that work with alloys containing small amounts of beryllium.
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A successful test for beryllium on different surface areas has been recently developed. This technique, in which beryllium is bound to a fluorescent chemical (sulfonated hydroxybenzoquinoline), enables the detection of beryllium at concentrations up to ten times below the recommended limit for the workplace.
[[Image:Be foil square.jpg|thumb|right|350px|A square beryllium foil mounted in a steel case to be used as a window between a vacuum chamber and an [[X-ray microscope]]. Beryllium, due to its low Z number is highly transparent to X-rays.]]
 
 
 
====Chronic beryllium disease (CBD)====
 
Some people (1-15%) become sensitive to beryllium. These individuals may develop an inflammatory reaction that principally targets the respiratory system and skin. This condition is called chronic beryllium disease (CBD), and can occur within a few months or many years after exposure to higher than normal levels of beryllium (greater than 0.02 µg/m³). This disease causes fatigue, weakness, night sweats and can cause difficulty in breathing and a persistent dry cough. It can result in anorexia, weight loss, and may also lead to right-side heart enlargement and heart disease in advanced cases. Some people who are sensitized to beryllium may not have any symptoms. The disease is treatable but not curable. CBD occurs when the body's immune system recognizes beryllium particles as foreign material and mounts an immune system attack against the particles. Because these particles are typically inhaled into the lungs, the lungs becomes the major site where the immune system responds. The lungs become inflamed, filled with large numbers of white blood cells that accumulate wherever beryllium particles are found. The cells form balls around the beryllium particles called "granulomas."  When enough of these granulomas develop, they interfere with the normal function of the organ. Over time, the lungs become stiff and lose their ability to help transfer oxygen from the air into the bloodstream. Patients with CBD develop difficulty inhaling and exhaling sufficient amounts of air and the amount of oxygen in their bloodstreams falls. Treatment of such patients includes use of oxygen and medicines that try to suppress the immune system's over-reaction to beryllium. A class of immunosuppressive medicines called glucocorticoids (example: prednisone), is most commonly used as treatment. The general population is unlikely to develop acute or chronic beryllium disease because ambient air levels of beryllium are normally very low (0.00003-0.0002 µg/m³).
 
 
 
=== Ingestion ===
 
 
 
Swallowing beryllium has not been reported to cause effects in humans because very little beryllium is absorbed from the stomach and intestines. Ulcers have been seen in dogs ingesting beryllium in the diet. Beryllium contact with skin that has been scraped or cut may cause [[rash]]es or ulcers, or bumps under the skin called "granulomas."
 
 
 
=== Effects on children ===
 
 
 
There are no studies on the health effects of children exposed to beryllium, although individual cases of CBD have been reported in children of beryllium workers from the 1940s. It is likely that the health effects seen in children exposed to beryllium will be similar to the effects seen in adults. It is unknown whether children differ from adults in their susceptibility to beryllium. It is unclear whether beryllium is [[teratogenic]].
 
 
 
=== Detection in the body ===
 
 
 
Beryllium can be measured in the urine and blood. The amount of beryllium in blood or urine may not indicate time or quantity of exposure. Beryllium levels can also be measured in lung and skin samples. While such measurements may help establish that exposure has occurred, other tests are used to determine if that exposure has resulted in health effects. A blood test, the blood beryllium lymphocyte proliferation test (BeLPT), identifies beryllium sensitization and has predictive value for CBD. The BeLPT has become the standard test for detecting beryllium sensitization and CBD in individuals who are suspected of having CBD and to help distinguish it from similar conditions such as sarcoidosis. It is also the main test used in industry health programs to monitor whether disease is occurring among current and former workers who have been exposed to beryllium on the job.  The test can detect disease that is at an early stage, or can detect disease at more advanced stages of illness as well.  The BeLPT can also be performed using cells obtained from a person's lung by a procedure called "bronchoscopy."
 
  
 
== Industrial release limits ==
 
== Industrial release limits ==
  
Typical levels of beryllium that industries may release into the air are of the order of 0.01 µg/m³, averaged over a 30-day period, or 2 µg/m³ of workroom air for an 8-hour work shift. Compliance with the current U.S. Occupational Safety and Health Administration (OSHA) permissible exposure limit for beryllium of 2 µg/m³ has been determined to be inadequate to protect workers from developing beryllium sensitization and CBD. The American Conference of Governmental Industrial Hygienists (ACGIH), which is an independent organization of experts in the field of occupational health, has proposed a threshold limit value (TLV) of 0.05 µg/m³ in a 2006 Notice of Intended Change (NIC). This TLV is 40 times lower than the current OHSA permissible exposure limit, reflecting the ACGIH analysis of best available peer-reviewed research data concerning how little airborne beryllium is required to cause sensitization and CBD. Because it can be difficult to control industrial exposures to beryllium, it is advisable to use any methods possible to reduce airborne and surface contamination by beryllium, to minimize the use of beryllium and beryllium-containing alloys whenever possible, and to educate people about the potential hazards if they are likely to encounter beryllium dust or fumes.
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Typical levels of beryllium that industries may release into the air are on the order of 0.01 micrograms per cubic meter (µg/m³), averaged over a 30-day period, or two µg/m³ of workroom air for an eight-hour work shift. The current U.S. Occupational Safety and Health Administration (OSHA) permissible exposure limit for beryllium is two µg/m³, but this figure has been challenged as inadequate for protecting workers from developing beryllium sensitization and CBD. The American Conference of Governmental Industrial Hygienists (ACGIH), an independent organization of experts in the field of occupational health, has proposed a threshold limit value (TLV) of 0.05 µg/m³, in a 2006 Notice of Intended Change (NIC). As it can be difficult to control industrial exposures to beryllium, it is advisable to use any methods possible to reduce airborne and surface contamination by beryllium, to minimize the use of beryllium and beryllium-containing alloys whenever possible, and to educate people about the potential hazards if they are likely to encounter beryllium dust or fumes.
  
 
==See also==
 
==See also==
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* [[Periodic table]]
 
* [[Periodic table]]
  
==Footnotes==
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==Notes==
 
<references/>
 
<references/>
  
 
==References==
 
==References==
 
*[http://periodic.lanl.gov/elements/4.html Los Alamos National Laboratory &ndash; Beryllium]
 
 
*[http://minerals.usgs.gov/minerals/pubs/commodity/beryllium USGS: Beryllium Statistics and Information]
 
 
*Burrell, AK. Ehler, DS. McClesky, TM. Minogue, EM. Taylor, TP. Development of a New Fluorescence Method for the Detection of Beryllium on Surfaces. Journal of ASTM International (JAI). 2005. Vol 2: Issue 9. http://www.astm.org/cgi-bin/SoftCart.exe/JOURNALS/JAI/PAGES/JAI13168.htm?E+mystore
 
 
*Infante PF, Newman LS.  Commentary: Beryllium exposure and Chronic Beryllium Disease.  Lancet 2004; 415-16.
 
 
*Newman LS. Beryllium. Chemical & Engineering News, 2003; 36:38.
 
 
*Kelleher PC, Martyny JW, Mroz MM, Maier LA, Ruttenber JA, Young  DA, Newman LS.  Beryllium particulate exposure and disease relations in a beryllium machining plant.  J Occup Environ Med 2001; 43:238-249.
 
 
*Mroz MM, Balkissoon R, Newman LS.  Beryllium.  In: Bingham E, Cohrssen B, Powell C (eds.)  Patty’s Toxicology, Fifth Edition.  New York:  John Wiley & Sons 2001, 177-220.
 
  
 
*Beryllium and Compounds: TLV® Chemical Substances Draft Documentation, Notice of Intended Change ACGIH® Publication #7NIC-042
 
*Beryllium and Compounds: TLV® Chemical Substances Draft Documentation, Notice of Intended Change ACGIH® Publication #7NIC-042
 +
*Burrell, A.K., D.S. Ehler, T.M. McClesky, E.M. Minogue, and T.P. Taylor. "Development of a New Fluorescence Method for the Detection of Beryllium on Surfaces." ''Journal of ASTM International (JAI)'' (2)9 (2005).
 +
*[http://www.ccohs.ca/oshanswers/diseases/beryllium.html Canadian Centre for Occupational Health and Safety: Beryllium Disease] Retrieved August 28, 2019.
 +
*Infante P.F., and L.S. Newman. Commentary: Beryllium exposure and Chronic Beryllium Disease. Lancet 2004, 415-16.
 +
*Kelleher, P.C., J.W. Martyny, M.M. Mroz, L.A. Maier, J.A. Ruttenber, D.A.Young, and L.S. Newman. Beryllium particulate exposure and disease relations in a beryllium machining plant. J Occup Environ Med 43 (2001): 238-249.
 +
*Mroz, M.M., R. Balkissoon, and L.S. Newman. Beryllium. ‘’Patty’s Toxicology’’, Fifth Edition. New York: John Wiley & Sons, 2001.
 +
*Newman, L.S. Beryllium. Chemical & Engineering News 36(38) (2003).
 +
*[http://minerals.usgs.gov/minerals/pubs/commodity/beryllium USGS: Beryllium Statistics and Information] Retrieved August 28, 2019.
  
 
==External links==
 
==External links==
 +
All links retrieved January 20, 2022.
  
* [http://www.compchemwiki.org/index.php?title=Beryllium Computational Chemistry Wiki]
 
 
* [http://education.jlab.org/itselemental/ele004.html It's Elemental &ndash; Beryllium]
 
* [http://education.jlab.org/itselemental/ele004.html It's Elemental &ndash; Beryllium]
* [http://www.npi.gov.au/database/substance-info/profiles/13.html National Pollutant Inventory - Beryllium and compounds]
 
 
* [http://www.webelements.com/webelements/elements/text/Be/index.html WebElements.com &ndash; Beryllium]
 
* [http://www.webelements.com/webelements/elements/text/Be/index.html WebElements.com &ndash; Beryllium]
  

Revision as of 01:00, 21 January 2022

4 lithiumberylliumboron
-

Be

Mg
Be-TableImage.png
periodic table
General
Name, Symbol, Number beryllium, Be, 4
Chemical series alkaline earth metals
Group, Period, Block 2, 2, s
Appearance white-gray metallic
Be foils.jpg
Atomic mass 9.012182(3) g/mol
Electron configuration 1s2 2s2
Electrons per shell 2, 2
Physical properties
Phase solid
Density (near r.t.) 1.85 g/cm³
Liquid density at m.p. 1.690 g/cm³
Melting point 1560 K
(1287 °C, 2349 °F)
Boiling point 2742 K
(2469 °C, 4476 °F)
Heat of fusion 7.895 kJ/mol
Heat of vaporization 297 kJ/mol
Heat capacity (25 °C) 16.443 J/(mol·K)
Vapor pressure
P/Pa 1 10 100 1 k 10 k 100 k
at T/K 1462 1608 1791 2023 2327 2742
Atomic properties
Crystal structure hexagonal
Oxidation states 2
(amphoteric oxide)
Electronegativity 1.57 (Pauling scale)
Ionization energies
(more)
1st: 899.5 kJ/mol
2nd: 1757.1 kJ/mol
3rd: 14848.7 kJ/mol
Atomic radius 105 pm
Atomic radius (calc.) 112 pm
Covalent radius 90 pm
Miscellaneous
Magnetic ordering diamagnetic
Electrical resistivity (20 °C) 35.6 nΩ·m
Thermal conductivity (300 K) 200 W/(m·K)
Thermal expansion (25 °C) 11.3 µm/(m·K)
Speed of sound (thin rod) (r.t.) 12870 m/s
Speed of sound (thin rod) (r.t.) 287 m/s
Shear modulus 132 GPa
Bulk modulus 130 GPa
Poisson ratio 0.032
Mohs hardness 5.5
Vickers hardness 1670 MPa
Brinell hardness 600 MPa
CAS registry number 7440-41-7
Notable isotopes
Main article: Isotopes of beryllium
iso NA half-life DM DE (MeV) DP
7Be syn 53.12 d ε - 7Li
γ 0.477 -
9Be 100% Be is stable with 5 neutrons
10Be trace 1.51×106 y β- 0.556 10B

Beryllium (chemical symbol Be, atomic number 4) ranks among the lightest of all known metals. Steel-gray in color, it is strong but brittle. It is classified as an alkaline earth metal, along with calcium and magnesium. Precious forms of its mineral beryl are aquamarine and emerald. This metal, its alloys, and compounds are toxic and need to be handled with care. One needs to especially avoid inhaling their dust and vapors.

Alloys of beryllium with copper or nickel are strong and wear-resistant, and are widely used in the manufacture of such items as computer parts, gyroscopes, electrodes, springs, and nonsparking tools. In addition, its alloys are useful as lightweight structural materials for high-speed aircraft, missiles, spacecraft, and satellites. The nuclear power industry uses beryllium in nuclear reactors as a neutron reflector and moderator. In X-ray lithography, beryllium is used for the reproduction of microscopic integrated circuits. Beryllium oxide is useful for applications that require an excellent heat conductor and electrical insulator, with a very high melting point and high strength and hardness.

Occurrence and production

Beryllium ore

Beryllium is a significant constituent of about 100 minerals. The most important of these are beryl (Al2Be3Si6O18), bertrandite (Be4Si2O7(OH)2), chrysoberyl (Al2BeO4), and phenakite (Be2SiO4). Precious forms of beryl are aquamarine and emerald.

The main commercial sources of beryllium and its compounds are beryl and bertrandite. Beryllium metal did not become readily available until 1957. Currently, the chief method of production is by reducing beryllium fluoride with magnesium metal. The chemical reaction can be written in terms of the following equation.

BeF2 + Mg → MgF2 + Be

Etymology and Discovery

The name beryllium comes from the Greek word beryllos, for "beryl." That, in turn, can be traced back to the Prakrit veruliya, from Pāli veuriya. These words appear akin to the Tamil veliru or vilar, meaning "to whiten, become pale."[1] At one time, beryllium was referred to as glucinium (from the Greek word glykys, meaning "sweet"), based on the sweet taste of its salts.

Beryllium was discovered by Louis Vauquelin in 1798, as the oxide in beryl and emeralds. In 1828, Friedrich Wöhler and Antoine Bussy independently isolated the metal by reacting potassium with beryllium chloride.

Notable characteristics

Beryllium is a member of the family of alkaline earth metals and lies at the top of group two (former group 2A) of the periodic table, just above magnesium. In addition, it is situated in period two, between lithium and boron. Among the light metals, beryllium has one of the highest melting points. Its modulus of elasticity (a measure of its elasticity) is approximately one-third more than that of steel. It is nonmagnetic and an excellent conductor of heat. The speed of sound in beryllium is about 12,500 meters per second—greater than that through any other element. Highly permeable to X-rays, it liberates neutrons when struck by alpha particles.

Beryllium resists attack by concentrated nitric acid. In addition, at standard temperature and pressure (0°C, 100 kPa), it resists oxidation when exposed to air. It appears, however, that its ability to scratch glass may be due to the formation of a thin layer of its oxide.

Isotopes

Beryllium has ten isotopes, of which only 9Be is stable. The isotope 10Be is produced in the atmosphere by the impact of cosmic rays on oxygen and nitrogen. This beryllium (being soluble in water at pH below 5.5) readily dissolves in rainwater (which generally has a pH less than five) and is transported to the Earth's surface. As this water quickly becomes more alkaline, 10Be drops out of solution and accumulates at the soil surface. Given its half-life of 1.51 million years, 10Be has a long residence time before it decays to 10B (an isotope of boron). The isotope 10Be and its daughter products have therefore been used to examine soil erosion, soil formation from regolith, and the development of lateritic soils. It has also been used to check variations in solar activity and the age of ice cores.

The instability of the isotopes 7Be and 8Be has profound consequences for cosmological theory. It means that elements heavier than beryllium could not have been produced by nuclear fusion at the time of the Big Bang. Moreover, the nuclear energy levels of 8Be are such that carbon can be produced within stars, thus making it possible for the eventual development of living organisms.

The shortest-lived isotope of beryllium is 13Be, which has a half-life of 2.7 × 10-21 seconds and decays through neutron emission. The isotope 6Be also is also very short-lived, with a half-life of 5.0 × 10-21 seconds.

Applications

A square beryllium foil mounted in a steel case is ready to be used as a window between a vacuum chamber and an X-ray microscope. Beryllium filters out visible light but is highly transparent to X-rays.
  • Beryllium-copper alloys (containing about two percent beryllium) are strong, hard, wear-resistant, and good conductors of heat and electricity. They are useful for gyroscopes, computer parts, and instruments requiring such properties.
  • The alloy with nickel (98 percent nickel, two percent beryllium) is used in the manufacture of spot-welding electrodes, springs, and nonsparking tools.
  • In addition, beryllium alloys are used by the defense and aerospace industries in the production of lightweight structural materials for high-speed aircraft, missiles, space vehicles, and communication satellites.
  • Thin sheets of beryllium foil are used with X-ray detection diagnostics, as the foil can filter out visible light and allow only X-rays to pass through.
  • In the field of X-ray lithography, beryllium is used for the reproduction of microscopic integrated circuits.
  • In the telecommunications industry, beryllium is made into tools that can be safely used for tuning the highly magnetic klystrons (specialized vacuum tubes) employed in high-power microwave transmissions.
  • The nuclear power industry uses this metal in nuclear reactors as a neutron reflector and moderator.
  • Beryllium is used in nuclear weapons for similar reasons. For example, the critical mass of a plutonium sphere is significantly reduced if the plutonium is surrounded by a beryllium shell.
  • Beryllium is sometimes used in neutron sources, in which the beryllium is mixed with an alpha emitter such as 210Po, 226Ra, 239Pu, or 241Am.
  • Beryllium is also used in making gyroscopes and various computer components, where lightweight materials with rigidity and dimensional stability are needed.
  • Beryllium is being used in the Joint European Torus fusion research facility, to condition the plasma-facing components
  • Beryllium oxide is useful for applications that require an excellent heat conductor and electrical insulator, with a very high melting point and high strength and hardness.

Health effects

Beryllium, its alloys, and its salts are toxic, and one should especially avoid inhaling their dust and fumes. Exposure to these materials can lead to two types of conditions: acute beryllium disease (acute berylliosis) and chronic beryllium disease (chronic berylliosis).[2] In addition, long-term exposure can increase the risk of developing lung cancer.

An acute condition is that which develops after a short, heavy exposure and lasts for no more than a year. Depending on the type of exposure, acute beryllium disease may involve inflammation of the skin (contact dermatitis), nose and throat (nasopharyngitis), windpipe (tracheobronchitis), or lungs (pneumonitis).

Chronic beryllium disease develops after prolonged (months or years) of exposure to beryllium. The time lapse between first exposure and symptoms of the disease may be as much as ten to 15 years. The chronic disease affects mainly the lungs but its effects may also be seen in other organs. The condition produces lesions and granulomas (tissue masses) mainly in the lungs, but it may also affect other organs, such as the skin, liver, kidney, heart, bone, lymphatic system, and nervous system. Symptoms of the chronic disease include coughing, chest pain, and breathing difficulties.

Acute chemical pneumonitis was first reported in Europe in 1933 and in the United States in 1943. Cases of chronic berylliosis were first described in 1946 among workers in plants manufacturing fluorescent lamps in Massachusetts, and the use of beryllium compounds in fluorescent lighting tubes was discontinued in 1949. The potential for exposure to beryllium exists in the nuclear and aerospace industries, the refining of beryllium metal, melting of beryllium-containing alloys, the manufacture of electronic devices, and the handling of other beryllium-containing materials.

Early researchers tasted beryllium and its various compounds for sweetness, to verify its presence. Modern diagnostic equipment no longer necessitates this highly risky procedure, and no attempt should be made to ingest this substance. Beryllium and its compounds should be handled with great care, and special precautions must be taken when carrying out any activity that may involve the release of beryllium dust. No attempt should be made to work with beryllium before familiarization with correct handling procedures.

A successful test for beryllium on different surface areas has been recently developed. This technique, in which beryllium is bound to a fluorescent chemical (sulfonated hydroxybenzoquinoline), enables the detection of beryllium at concentrations up to ten times below the recommended limit for the workplace.

Industrial release limits

Typical levels of beryllium that industries may release into the air are on the order of 0.01 micrograms per cubic meter (µg/m³), averaged over a 30-day period, or two µg/m³ of workroom air for an eight-hour work shift. The current U.S. Occupational Safety and Health Administration (OSHA) permissible exposure limit for beryllium is two µg/m³, but this figure has been challenged as inadequate for protecting workers from developing beryllium sensitization and CBD. The American Conference of Governmental Industrial Hygienists (ACGIH), an independent organization of experts in the field of occupational health, has proposed a threshold limit value (TLV) of 0.05 µg/m³, in a 2006 Notice of Intended Change (NIC). As it can be difficult to control industrial exposures to beryllium, it is advisable to use any methods possible to reduce airborne and surface contamination by beryllium, to minimize the use of beryllium and beryllium-containing alloys whenever possible, and to educate people about the potential hazards if they are likely to encounter beryllium dust or fumes.

See also

Notes

References
ISBN links support NWE through referral fees

  • Beryllium and Compounds: TLV® Chemical Substances Draft Documentation, Notice of Intended Change ACGIH® Publication #7NIC-042
  • Burrell, A.K., D.S. Ehler, T.M. McClesky, E.M. Minogue, and T.P. Taylor. "Development of a New Fluorescence Method for the Detection of Beryllium on Surfaces." Journal of ASTM International (JAI) (2)9 (2005).
  • Canadian Centre for Occupational Health and Safety: Beryllium Disease Retrieved August 28, 2019.
  • Infante P.F., and L.S. Newman. Commentary: Beryllium exposure and Chronic Beryllium Disease. Lancet 2004, 415-16.
  • Kelleher, P.C., J.W. Martyny, M.M. Mroz, L.A. Maier, J.A. Ruttenber, D.A.Young, and L.S. Newman. Beryllium particulate exposure and disease relations in a beryllium machining plant. J Occup Environ Med 43 (2001): 238-249.
  • Mroz, M.M., R. Balkissoon, and L.S. Newman. Beryllium. ‘’Patty’s Toxicology’’, Fifth Edition. New York: John Wiley & Sons, 2001.
  • Newman, L.S. Beryllium. Chemical & Engineering News 36(38) (2003).
  • USGS: Beryllium Statistics and Information Retrieved August 28, 2019.

External links

All links retrieved January 20, 2022.

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