Lithium ( /ˈlɪθiəm/, LI-thee-əm) is a soft, silver-white metal that belongs to the alkali metal group of chemical elements. It is represented by the symbol Li,
and it has the atomic number 3. Under standard conditions it is the
lightest metal and the least dense solid element. Like all alkali
metals, lithium is highly reactive and flammable. For this reason, it is
typically stored in mineral oil. When cut open, lithium exhibits a
metallic luster, but contact with moist air corrodes the surface quickly
to a dull silvery gray, then black, tarnish. Because of its high
reactivity, lithium never occurs free in nature, and instead, only
appears in compounds, usually ionic ones. Lithium occurs in a number of
pegmatitic minerals, but is also commonly obtained from brines and
clays. On a commercial scale, lithium is isolated electrolytically from a
mixture of lithium chloride and potassium chloride.
The nuclei of
lithium are not far from being unstable, since the two stable lithium
isotopes found in nature have among the lowest binding energies per
nucleon of all stable nuclides. As a result, they can be used in fission
reactions as well as fusion reactions of nuclear devices. Due to its
near instability, lithium is less common in the solar system than 25 of
the first 32 chemical elements even though the nuclei are very light
in atomic weight.[1] For related reasons, lithium has important links to
nuclear physics. The transmutation of lithium atoms to tritium was the
first man-made form of a nuclear fusion reaction, and lithium deuteride
serves as a fusion fuel in staged thermonuclear weapons.
Trace
amounts of lithium are present in the oceans and in all organisms. The
element serves no apparent vital biological function, since animal and
plants survive in good health without it. Nonvital functions have not
been ruled out. The lithium ion Li+ administered as any of several
lithium salts has proved to be useful as a mood-stabilizing drug due to
neurological effects of the ion in the human body. Lithium and its
compounds have several industrial applications, including heat-resistant
glass and ceramics, high strength-to-weight alloys used in aircraft,
lithium batteries and lithium-ion batteries. These uses consume more
than half of lithium production.
Contents
[hide]
- 1 Characteristics
- 1.1 Atomic and physical
- 1.2 Chemistry and compounds
- 1.3 Isotopes
- 2 Occurrence
- 2.1 Astronomical
- 2.2 Terrestrial
- 3 History
- 4 Production
- 5 Applications
- 5.1 Electrical and electronics
- 5.2 Medicinal
- 5.3 Chemical and industrial
- 5.4 Nuclear
- 5.5 Other uses
- 6 Precautions
- 7 See also
- 8 Notes
- 9 References
- 10 External links
Characteristics
Main article: Alkali metal
Atomic and physical
Lithium pellets covered in white lithium hydroxide (left) and ingots with a thin layer of black oxide tarnish (right)
Like
the other alkali metals, lithium has a single valence electron that is
easily given up to form a cation.[2] Because of this, it is a good
conductor of heat and electricity as well as a highly reactive element,
though the least reactive of the even-more highly reactive alkali
metals. Lithium's low reactivity compared to other alkali metals is
thought to be due to the proximity of its valence electron to its
nucleus (the remaining two electrons in lithium's 1s orbital and are
much lower in energy, and therefore they do not participate in chemical
bonds).[2]
Lithium metal is soft enough to be cut with a knife.
When cut, it possesses a silvery-white color that quickly changes to
gray due to oxidation.[2] While it has one of the lowest melting points
among all metals (180 °C), it has the highest melting point of the
alkali metals.[3]
It is the lightest metal in the periodic table.
It has a very low density, of approximately 0.534 g/cm3, which gives
sticks of the metal a similar heft to dowels of a medium density wood,
such as pine. It floats on water but also reacts with it.[2] It is the
least dense of all elements that are not gasses at room temperature.
The next lightest element is over 60% more dense (potassium, at 0.862
g/cm3). Furthermore, aside from helium and hydrogen, it is the least
dense element in a solid or liquid state, being only 2/3 as dense as
liquid nitrogen (0.808 g/cm3).[note 1][4]
Lithium's coefficient of
thermal expansion is twice that of aluminum and almost four times that
of iron.[5] It has the highest specific heat capacity of any solid
element. Lithium is superconductive below 400 μK at standard pressure[6]
and at higher temperatures (more than 9 K) at very high pressures
(>20 GPa)[7] At temperatures below 70 K, lithium, like sodium,
undergoes diffusionless phase change transformations. At 4.2 K it has a
rhombohedral crystal system (with a nine-layer repeat spacing); at
higher temperatures it transforms to face-centered cubic and then
body-centered cubic. At liquid-helium temperatures (4 K) the
rhombohedral structure is the most prevalent.[8] Multiple allotropic
forms have been reported for lithium at high pressures.[9]
Chemistry and compounds
Lithium
reacts with water easily, but with noticeably less energy than other
alkali metals do. The reaction forms hydrogen gas and lithium hydroxide
in aqueous solution.[2] Because of its reactivity with water, lithium is
usually stored under cover of a viscous hydrocarbon, often petroleum
jelly. Though the heavier alkali metals can be stored in less dense
substances, such as mineral oil, lithium is not dense enough to be fully
submerged in these liquids.[10] In moist air, lithium rapidly tarnishes
to form a black coating of lithium hydroxide (LiOH and LiOH·H2O),
lithium nitride (Li3N) and lithium carbonate (Li2CO3, the result of a
secondary reaction between LiOH and CO2).[11]
When placed over a
flame, lithium compounds give off a striking crimson color, but when it
burns strongly the flame becomes a brilliant silver. Lithium will
ignite and burn in oxygen when exposed to water or water vapors.[12]
Lithium is flammable, and it is potentially explosive when exposed to
air and especially to water, though less so than the other alkali
metals. The lithium-water reaction at normal temperatures is brisk but
not violent, though the hydrogen produced can ignite. As with all
alkali metals, lithium fires are difficult to extinguish, requiring dry
powder fire extinguishers, specifically Class D type (see Types of
extinguishing agents). Lithium is the only metal which reacts with
nitrogen under normal conditions.[13][14]
Hexameric structure of the LiBu fragment in a crystal
Lithium
has a diagonal relationship with magnesium, an element of similar
atomic and ionic radius. Chemical resemblances between the two metals
include the formation of a nitride by reaction with N2, the formation of
an oxide (Li2O) and peroxide (Li2O2) when burnt in O2, salts with
similar solubilities, and thermal instability of the carbonates and
nitrides.[11][15] The metal reacts with hydrogen gas at high
temperatures to produce lithium hydride (LiH).[16]
Other known
binary compounds include the halides (LiF, LiCl, LiBr, LiI), and the
sulfide (Li2S), the superoxide (LiO2), carbide (Li2C2). Many other
inorganic compounds are known, where lithium combines with anions to
form various salts: borates, amides, carbonate, nitrate, or borohydride
(LiBH4). Multiple organolithium reagents are known where there is a
direct bond between carbon and lithium atoms effectively creating a
carbanion that are extremely powerful bases and nucleophiles. In many
of these organolithium compounds, the lithium ions tend to aggregate
into high-symmetry clusters by themselves, which is relatively common
for alkali cations.[17]
Isotopes
Main article: Isotopes of lithium
Naturally
occurring lithium is composed of two stable isotopes, 6Li and 7Li, the
latter being the more abundant (92.5% natural abundance).[2][10][18]
Both natural isotopes have anomalously low nuclear binding energy per
nucleon compared to the next lighter and heavier elements, helium and
beryllium, which means that alone among stable light elements, lithium
can produce net energy through nuclear fission. The two lithium nuclei
have lower binding energies per nucleon than any other stable compound
nuclides other than deuterium, and helium-3.[19] As a result of this,
though very light in atomic weight, lithium is less common in the solar
system than 25 of the first 32 chemical elements.[20] Seven
radioisotopes have been characterized, the most stable being 8Li with a
half-life of 838 ms and 9Li with a half-life of 178 ms. All of the
remaining radioactive isotopes have half-lives that are shorter than
8.6 ms. The shortest-lived isotope of lithium is 4Li, which decays
through proton emission and has a half-life of 7.6 × 10−23 s.[21]
7Li
is one of the primordial elements (or, more properly, primordial
isotopes) produced in Big Bang nucleosynthesis. A small amount of both
6Li and 7Li are produced in stars, but are thought to be burned as fast
as produced.[22] Additional small amounts of lithium of both 6Li and 7Li
may be generated from solar wind, cosmic rays hitting heavier atoms,
and from early solar system 7Be and 10Be radioactive decay.[23] While
lithium is created in stars during the Stellar nucleosynthesis, it is
further burnt. 7Li can also be generated in carbon stars.[24]
Lithium
isotopes fractionate substantially during a wide variety of natural
processes,[25] including mineral formation (chemical precipitation),
metabolism, and ion exchange. Lithium ions substitute for magnesium and
iron in octahedral sites in clay minerals, where 6Li is preferred to
7Li, resulting in enrichment of the light isotope in processes of
hyperfiltration and rock alteration. The exotic 11Li is known to exhibit
a nuclear halo. The process known as laser isotope separation can be
used to separate lithium isotopes.[26]
Occurrence
Lithium is about as common as chlorine in the Earth's upper continental crust, on a per-atom basis.
Astronomical
Main article: Nucleosynthesis
According
to modern cosmological theory, lithium—as both of its stable isotopes
lithium-6 and lithium-7—was among the 3 elements synthesized in the Big
Bang. Though the amount of lithium generated in Big Bang nucleosynthesis
is dependent upon the number of photons per baryon, for accepted
values the lithium abundance can be calculated, and there is a
"cosmological lithium discrepancy" in the Universe: older stars seem to
have less lithium than they should, and some younger stars have far
more. The lack of lithium in older stars is apparently caused by the
"mixing" of lithium into the interior of stars, where it is
destroyed.[27] Furthermore, lithium is produced in younger stars. Though
it transmutes into two atoms of helium due to collision with a proton
at temperatures above 2.4 million degrees Celsius (most stars easily
attain this temperature in their interiors), lithium is more abundant
than predicted in later-generation stars, for causes not yet completely
understood.[10]
Though it was one of the three first elements
(together with helium and hydrogen) to be synthesized in the Big Bang,
lithium, together with beryllium and boron are markedly less abundant
than other nearby elements. This is a result to the low temperature
necessary to destroy lithium, and a lack of common processes to produce
it.[28]
Lithium is also found in brown dwarf stars and certain
anomalous orange stars. Because lithium is present in cooler,
less-massive brown dwarf stars, but is destroyed in hotter red dwarf
stars, its presence in the stars' spectra can be used in the "lithium
test" to differentiate the two, as both are smaller than the
Sun.[10][29][30] Certain orange stars can also contain a high
concentration of lithium. Those orange stars found to have a higher
than usual concentration of lithium (such as Centaurus X-4) orbit
massive objects—neutron stars or black holes—whose gravity evidently
pulls heavier lithium to the surface of a hydrogen-helium star, causing
more lithium to be observed.[10]
Terrestrial
Lithium mine production (2009) and reserves in tonnes[31]
Country Production Reserves
Argentina 2,200 800,000
Australia 4,400 580,000
Brazil 110 190,000
Canada 480 180,000
Chile 7,400 7,500,000
People's Republic of China 2,300 540,000
Portugal 490 Not available
United States Withheld 38,000
Zimbabwe 350 23,000
World total 18,000 9,900,000
See also: Lithium minerals
Although
lithium is widely distributed on Earth, it does not naturally occur in
elemental form due to its high reactivity.[2] The total lithium content
of seawater is very large and is estimated as 230 billion tonnes,
where the element exists at a relatively constant concentration of 0.14
to 0.25 parts per million (ppm),[32][33] or 25 micromolar;[34] higher
concentrations approaching 7 ppm are found near hydrothermal vents.[33]
Estimates
for crustal content range from 20 to 70 ppm by weight.[11] In keeping
with its name, lithium forms a minor part of igneous rocks, with the
largest concentrations in granites. Granitic pegmatites also provide the
greatest abundance of lithium-containing minerals, with spodumene and
petalite being the most commercially viable sources.[11] A newer source
for lithium is hectorite clay, the only active development of which is
through the Western Lithium Corporation in the United States.[35] At
20 mg lithium per kg of Earth's crust,[36] lithium is the 25th most
abundant element. Nickel and lead have about the same abundance.
Lithium
is found in trace amount in numerous plants, plankton, and
invertebrates, at concentrations of 69 to 5,760 parts per billion (ppb).
In vertebrates the concentration is slightly lower, and nearly all
vertebrate tissue and body fluids have been found to contain lithium
ranging from 21 to 763 ppb.[33] Marine organisms tend to bioaccumulate
lithium more than terrestrial ones.[37] It is not known whether lithium
has a physiological role in any of these organisms.[33]
According to the Handbook of Lithium and Natural Calcium,
"Lithium is a comparatively rare element, although it is found in many
rocks and some brines, but always in very low concentrations. There
are a fairly large number of both lithium mineral and brine deposits
but only comparatively a few of them are of actual or potential
commercial value. Many are very small, others are too low in
grade."[38]
The largest reserve base of lithium is in the Salar de
Uyuni area of Bolivia, which has 5.4 million tonnes. US Geological
Survey, estimates that in 2009 Chile had the largest reserves by far
(7.5 million tonnes) and the highest annual production (7,400 tonnes).
Other major suppliers include Australia, Argentina and China.[31][39]
Other estimates put Argentina's reserve base (7.52 million tonnes) above
that of Chile (6 million).[40]
In June 2010, the New York Times
reported that American geologists were conducting ground surveys on dry
salt lakes in western Afghanistan believing that large deposits of
lithium are located there. "Pentagon officials said that their initial
analysis at one location in Ghazni Province showed the potential for
lithium deposits as large of those of Bolivia, which now has the
world’s largest known lithium reserves." [41] These estimates are
"based principally on old data, which was gathered mainly by the
Soviets during their occupation of Afghanistan from 1979–1989" and
"Stephen Peters, the head of the USGS’s Afghanistan Minerals Project,
said that he was unaware of USGS involvement in any new surveying for
minerals in Afghanistan in the past two years. 'We are not aware of any
discoveries of lithium,' he said."[42]
History
Johan August Arfwedson is credited with the discovery of lithium in 1817
Petalite
(LiAlSi4O10) was discovered in 1800 by the Brazilian chemist José
Bonifácio de Andrada e Silva in a mine on the island of Utö,
Sweden.[43][44][45] However, it was not until 1817 that Johan August
Arfwedson, then working in the laboratory of the chemist Jöns Jakob
Berzelius, detected the presence of a new element while analyzing
petalite ore.[46][47][48] This element formed compounds similar to those
of sodium and potassium, though its carbonate and hydroxide were less
soluble in water and more alkaline.[49] Berzelius gave the alkaline
material the name "lithion/lithina", from the Greek word λιθoς (transliterated as lithos,
meaning "stone"), to reflect its discovery in a solid mineral, as
opposed to potassium, which had been discovered in plant ashes, and
sodium which was known partly for its high abundance in animal blood. He
named the metal inside the material as "lithium".[2][44][48]
Arfwedson
later showed that this same element was present in the minerals
spodumene and lepidolite.[44] In 1818, Christian Gmelin was the first to
observe that lithium salts give a bright red color to flame.[44]
However, both Arfwedson and Gmelin tried and failed to isolate the pure
element from its salts.[44][48][50] It was not isolated until 1821, when
William Thomas Brande obtained it by electrolysis of lithium oxide, a
process that had previously been employed by the chemist Sir Humphry
Davy to isolate the alkali metals potassium and sodium.[10][50][51][52]
Brande also described some pure salts of lithium, such as the chloride,
and, estimating that lithia (lithium oxide) contained about 55% metal,
estimated the atomic weight of lithium to be around 9.8 g/mol (modern
value ~6.94 g/mol).[53] In 1855, larger quantities of lithium were
produced through the electrolysis of lithium chloride by Robert Bunsen
and Augustus Matthiessen.[44] The discovery of this procedure henceforth
led to commercial production of lithium, beginning in 1923, by the
German company Metallgesellschaft AG, which performed an electrolysis of
a liquid mixture of lithium chloride and potassium chloride.[44][54]
The
production and use of lithium underwent several drastic changes in
history. The first major application of lithium became high temperature
grease for aircraft engines or similar applications in World War II
and shortly after. This small market was supported by several small
mining operations mostly in the United States. The demand for lithium
increased dramatically during the Cold War with the production of
nuclear fusion weapons. Both lithium-6 and lithium-7 produce tritium
when irradiated by neutrons, and are thus useful for the production of
tritium by itself, as well as a form of solid fusion fuel used inside
hydrogen bombs in the form of lithium deuteride. The United States
became the prime producer of lithium in the period between the late
1950s and the mid 1980s. At the end the stockpile of lithium was
roughly 42,000 tonnes of lithium hydroxide. The stockpiled lithium was
depleted in lithium-6 by 75%.[55]
Lithium was used to decrease the
melting temperature of glass and to improve the melting behavior of
aluminium oxide when using the Hall-Héroult process.[56][56] These two
uses dominated the market until the middle of the 1990s. After the end
of the nuclear arms race the demand for lithium decreased and the sale
of Department of Energy stockpiles on the open market further reduced
prices.[55] But in the mid-1990s, several companies started to extract
lithium from brine which proved to be a less expensive method than
underground or even open pit mining. Most of the mines closed or
shifted their focus to other materials as only the ore from zoned
pegmatites could be mined for a competitive price. For example, the US
mines near Kings Mountain, North Carolina closed before the turn of the
century. The use in lithium ion batteries increased the demand for
lithium and became the dominant use in 2007.[57] With the surge of
lithium demand in batteries in to 2000s, new companies have expanded
brine extraction efforts to meet the rising demand.[58][59]
Production
Satellite
images of the Salar del Hombre Muerto, Argentina (left), and Uyuni,
Bolivia (right), salt flats are rich in lithium. The lithium-rich brine
is concentrated by pumping it into solar evaporation ponds (visible in
the left image).
Since the end of World War II lithium production
has greatly increased. The metal is separated from other elements in
igneous minerals such as those above. Lithium salts are extracted from
the water of mineral springs, brine pools and brine deposits. The metal
is produced electrolytically from a mixture of fused lithium chloride
and potassium chloride. In 1998 it was about 95 US$ / kg (or 43
US$/pound).[60]
There are widespread hopes of using lithium ion
batteries in electric vehicles, but one study concluded that
"realistically achievable lithium carbonate production will be
sufficient for only a small fraction of future PHEV and EV global
market requirements", that "demand from the portable electronics sector
will absorb much of the planned production increases in the next
decade", and that "mass production of lithium carbonate is not
environmentally sound, it will cause irreparable ecological damage to
ecosystems that should be protected and that LiIon propulsion is
incompatible with the notion of the 'Green Car'".[61]
Deposits of
lithium are found in South America throughout the Andes mountain chain.
Chile is the leading lithium producer, followed by Argentina. Both
countries recover the lithium from brine pools. In the United States
lithium is recovered from brine pools in Nevada.[62] Nearly half the
world's known reserves are located in Bolivia, a nation sitting along
the central eastern slope of the Andes. In 2009 Bolivia is negotiating
with Japanese, French, and Korean firms to begin extraction.[63]
According to the US Geological Survey, Bolivia's Uyuni Desert has 5.4
million tonnes of lithium, which can be used to make batteries for
hybrid and electric vehicles.[63][64] China may emerge as a significant
producer of brine-source lithium carbonate around 2010. There is
potential production of up to 55,000 tonnes per year if projects in
Qinghai province and Tibet proceed.[61]
Worldwide reserves of
lithium are estimated to be 23 million tonnes.[65] Using the battery
efficiency figure of 400 g of lithium per kWh,[66] this gives a total
maximum lithium battery capacity of 52 billion kWh which, assuming it
is used exclusively for car batteries, is enough for approximately 2
billion cars with a 24 kWh battery (like a Nissan Leaf [67]).
Applications
Usage of lithium in the USA in 2009[68]
Electrical and electronics
In
the later years of the 20th century lithium became important as an
anode material. Used in lithium-ion batteries because of its high
electrochemical potential, a typical cell can generate approximately 3
volts, compared with 2.1 volts for lead/acid or 1.5 volts for
zinc-carbon cells. Because of its low atomic mass, it also has a high
charge- and power-to-weight ratio. Lithium batteries are disposable
(primary) batteries with lithium or its compounds as an anode. Lithium
batteries are not to be confused with lithium-ion batteries, which are
high energy-density rechargeable batteries. Other rechargeable batteries
include the lithium-ion polymer battery, lithium iron phosphate
battery, and the nanowire battery. New technologies are constantly being
announced.
Lithium niobate is used extensively in
telecommunication products such as mobile phones and optical modulators,
for such components as resonant crystals. Lithium applications are used
in more than 60% of mobile phones.[69] Because of its specific heat
capacity, the highest of all solids, lithium is often used in coolants
for heat transfer applications.[62]
Medicinal
Main article: Lithium pharmacology
Lithium
salts were used during the 19th century to treat gout. Lithium salts
such as lithium carbonate (Li2CO3), lithium citrate, and lithium orotate
are mood stabilizers. They are used in the treatment of bipolar
disorder since, unlike most other mood altering drugs, they counteract
both depression and mania (though more effective for the latter).
Lithium continues to be the gold standard for the treatment of bipolar
disorder. It is also helpful for related diagnoses, such as
schizoaffective disorder and cyclic major depression. In addition to
watching out for the well-known complications of lithium
treatment—hypothyroidism and decreased renal function—health care
providers should be aware of hyperparathyroidism.[70] Lithium can also
be used to augment antidepressants. Because of Lithium's nephrogenic
diabetes insipidus effects, it can be used to help treat the syndrome of
inappropriate antidiuretic hormone hypersecretion (SIADH). It was also
sometimes prescribed as a preventive treatment for migraine disease and
cluster headaches.[71]
The active principle in these salts is the
lithium ion Li+. Although this ion has a smaller diameter than either
Na+ or K+, in a watery environment like the cytoplasmic fluid, Li+ binds
to the oxygen atoms of water, making it effectively larger than either
Na+ or K+ ions. How Li+ works in the central nervous system is still a
matter of debate. Li+ elevates brain levels of tryptophan, 5-HT
(serotonin), and 5-HIAA (a serotonin metabolite). Serotonin is related
to mood stability. Li+ also reduces catecholamine activity in the brain
(associated with brain activation and mania), by enhancing reuptake and
reducing release. Therapeutically useful amounts of lithium (1.0 to
1.2 mmol/L) are only slightly lower than toxic amounts
(>1.5 mmol/L), so the blood levels of lithium must be carefully
monitored during treatment to avoid toxicity.[72]
Common side
effects of lithium treatment include muscle tremors, twitching, ataxia,
and hypothyroidism.[73] Long term use is linked to
hyperparathyroidism,[74] hypercalcemia (bone loss), hypertension, damage
of tubuli in the kidney, nephrogenic diabetes insipidus (polyuria and
polydipsia) and/or glomerular damage – even to the point of uremia,[75]
seizures[76] and weight gain.[77] According to a study in 2009 at Oita
University in Japan and published in the British Journal of Psychiatry,
communities whose water contained larger amounts of lithium had
significantly lower suicide rates,[78][79][80][81] but did not address
whether lithium in drinking water causes the negative side effects
associated with higher doses of the element.[82]
Chemical and industrial
Lithium use in flares and pyrotechnics is due to its red flame
Lithium
is also used in the pharmaceutical and fine-chemical industry in the
manufacture of organolithium reagents, which are used both as strong
bases and as reagents for the formation of carbon-carbon bonds.
Organolithium compounds are also used in polymer synthesis as
catalysts/initiators[83] in anionic polymerization of unfunctionalized
olefins.[84][85][86] Lithium is used in the preparation of organolithium
compounds, which are in turn very reactive and are the basis of many
synthetic applications.[87]
Lithium chloride and lithium bromide
are extremely hygroscopic and are used as desiccants.[62] Lithium
hydroxide (LiOH) is an important compound of lithium obtained from
lithium carbonate (Li2CO3). It is a strong base, and when heated with a
fat it produces a soap made of lithium stearate. Lithium soap has the
ability to thicken oils, and it is used to manufacture all-purpose,
high-temperature lubricating greases.[62][88][89]
When used as a
flux for welding or soldering, lithium promotes the fusing of metals
during and eliminates the forming of oxides by absorbing impurities. Its
fusing quality is also important as a flux for producing ceramics,
enamels and glass. Alloys of the metal with aluminium, cadmium, copper
and manganese are used to make high-performance aircraft parts (see also
Lithium-aluminium alloys). Lithium compounds are also used as
pyrotechnic colorants and oxidizers in red fireworks and flares.[62][90]
Nuclear
Lithium-6
is valued as a source material for tritium production and as a neutron
absorber in nuclear fusion. Natural lithium contains about 7.5%
lithium-6 from which large amounts of lithium-6 have been produced by
isotope separation for use in nuclear weapons.[91] Lithium-7 gained
interest for use in nuclear reactor coolants.[92]
Lithium deuteride was used as fuel in the Castle Bravo nuclear device.
Lithium
deuteride was the fusion fuel of choice in early versions of the
hydrogen bomb. When bombarded by neutrons, both 6Li and 7Li produce
tritium—this reaction, which was not fully understood when hydrogen
bombs were first tested, was responsible for the runaway yield of the
Castle Bravo nuclear test. Tritium fuses with deuterium in a fusion
reaction that is relatively easy to achieve. Although details remain
secret, lithium-6 deuteride still apparently plays a role in modern
nuclear weapons, as a fusion material.[93]
Lithium fluoride as
highly enriched in the lithium-7 isotope forms the basic constituent of
the fluoride salt mixture LiF-BeF2 that used in liquid-fluoride nuclear
reactors. Lithium fluoride is exceptionally chemically stable and
LiF-BeF2 mixtures have low melting points. In addition, 7Li, Be, and F
are among the few nuclides with low enough thermal neutron capture
cross-sections to not poison the fission reactions inside a nuclear
fission reactor.[note 2][94]
In conceptualized nuclear fusion
power plants, lithium will be used to produce tritium in magnetically
confined reactors using deuterium and tritium as the fuel. Tritium does
not occur naturally and will be produced by surrounding the reacting
plasma with a 'blanket' containing lithium where neutrons from the
deuterium-tritium reaction in the plasma will react with the lithium to
produce more tritium:
6Li + n → 4He + 3T.
Various means of doing this will be tested at the ITER reactor being built at Cadarache, France.[95]
Lithium
is also used as a source for alpha particles, or helium nuclei. When
7Li is bombarded by accelerated protons 8Be is formed, which undergoes
spontaneous fission to form two alpha particles. This was the first
man-made nuclear reaction, produced by Cockroft and Walton in 1929.[96]
Other uses
Lithium
fluoride, artificially grown as crystal, is clear and transparent and
often used in specialist optics for IR, UV and VUV (vacuum UV)
applications. It has one of the lowest refractive indexes and the
farthest transmission range in the deep UV of most common materials.[97]
Finely divided lithium fluoride powder has been used for
thermoluminescent radiation dosimetry (TLD): when a sample of such is
exposed to radiation, it accumulates crystal defects which, when heated,
resolve via a release of bluish light whose intensity is proportional
to the absorbed dose, thus allowing this to be quantified.[98] Lithium
fluoride is sometimes used in focal lenses of telescopes.[62][99] The
high non-linearity of lithium niobate also makes it useful in non-linear
optics applications.
The launch of a torpedo using lithium as fuel
Metallic
lithium and its complex hydrides, such a Li[AlH4], are used as high
energy additives to rocket propellants.[10] Lithium peroxide, lithium
nitrate, lithium chlorate and lithium perchlorate are used as oxidizers
in rocket propellants, and also in oxygen candles that supply submarines
and space capsules with oxygen.[100] The Mark 50 Torpedo Stored
Chemical Energy Propulsion System (SCEPS) uses a small tank of sulfur
hexafluoride gas which is sprayed over a block of solid lithium. The
reaction generates enormous heat which is used to generate steam from
seawater. The steam propels the torpedo in a closed Rankine cycle.[101]
Lithium
hydroxide and lithium peroxide are used in confined areas, such as
aboard spacecraft and submarines, for air purification. Lithium
hydroxide absorbs carbon dioxide from the air by reacting with it to
form lithium carbonate, and is preferred over other alkaline hydroxides
for its low weight. Lithium peroxide (Li2O2) in presence of moisture
not only absorbs carbon dioxide to form lithium carbonate, but also
releases oxygen.[102][103] For example:
2 Li2O2 + 2 CO2 → 2 Li2CO3 + O2.
Precautions
NFPA 704
0
3
2
W
The fire diamond hazard sign for lithium metal
Lithium
is corrosive and requires special handling to avoid skin contact.
Breathing lithium dust or lithium compounds (which are often alkaline)
initially irritate the nose and throat, while higher exposure can cause a
buildup of fluid in the lungs, leading to pulmonary edema. The metal
itself is a handling hazard because of the caustic hydroxide produced
when it is in contact with moisture. Lithium is safely stored in
non-reactive compounds such as naphtha.[104]
There have been
suggestions of increased risk of developing Ebstein's cardiac anomaly in
infants born to women taking lithium during the first trimester of
pregnancy.[105]
Regulation
Some
jurisdictions limit the sale of lithium batteries, which are the most
readily available source of lithium for ordinary consumers. Lithium can
be used to reduce pseudoephedrine and ephedrine to methamphetamine in
the Birch reduction method, which employs solutions of alkali metals
dissolved in anhydrous ammonia.[106][107] Carriage and shipment of some
kinds of lithium batteries may be prohibited aboard certain types of
transportation (particularly aircraft) because of the ability of most
types of lithium batteries to fully discharge very rapidly when
short-circuited, leading to overheating and possible explosion in a
process called thermal runaway. Most consumer lithium batteries have
thermal overload protection built-in to prevent this type of incident,
or their design inherently limits short-circuit currents. Internal
shorts have been known to develop due to manufacturing defects or
damage to batteries that can lead to spontaneous thermal
runaway.[108][109]
引用出處：
http://en.wikipedia.org/wiki/Lithium
歡迎來到Bewise Inc.的世界，首先恭喜您來到這接受新的資訊讓產業更有競爭力，我們是提供專業刀具製造商，應對客戶高品質的刀具需求，我們可以協助客戶滿足您對產業的不同要求，我們有能力達到非常卓越的客戶需求品質，這是現有相關技術無法比擬的，我們成功的滿足了各行各業的要求，包括：精密HSS DIN切削刀具、協助客戶設計刀具流程、DIN or JIS 鎢鋼切削刀具設計、NAS986 NAS965 NAS897 NAS937orNAS907 航太切削刀具,NAS航太刀具設計、超高硬度的切削刀具、醫療配件刀具設計、複合式再研磨機、PCD地板專用企口鑽石組合刀具、粉末造粒成型機、主機版專用頂級電桿、PCD V-Cut刀、捨棄式圓鋸片組、粉末成型機、航空機械鉸刀、主機版專用頂級電感、’汽車業刀具設計、電子產業鑽石刀具、木工產業鑽石刀具、銑刀與切斷複合再研磨機、銑刀與鑽頭複合再研磨機、銑刀與螺絲攻複合再研磨機等等。我們的產品涵蓋了從民生刀具到工業級的刀具設計；從微細刀具到大型刀具；從小型生產到大型量產；全自動整合；我們的技術可提供您連續生產的效能，我們整體的服務及卓越的技術，恭迎您親自體驗！！
BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com
skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office
No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 http://www.tool-tool.com/
/ FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North
Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao
City,Chiayi Hsien,Taiwan
Welcome to BW
tool world! We are an experienced tool maker specialized in cutting
tools. We focus on what you need and endeavor to research the best
cutter to satisfy users’ demand. Our
customers involve wide range of industries, like mold & die,
aerospace, electronic, machinery, etc. We are professional expert in
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feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS DIN Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、NAS986 NAS965 NAS897 NAS937orNAS907 Cutting Tools,Carbide end mill、disc milling cutter,Aerospace cutting tool、hss drill’Фрезеры’Carbide drill、High speed steel、Compound Sharpener’Milling cutter、INDUCTORS FOR PCD’CVDD(Chemical Vapor Deposition Diamond )’PCBN (Polycrystalline Cubic Boron Nitride) ’Core drill、Tapered end mills、CVD Diamond Tools Inserts’PCD Edge-Beveling Cutter(Golden Finger’PCD V-Cutter’PCD Wood tools’PCD Cutting tools’PCD Circular Saw Blade’PVDD End Mills’diamond tool. INDUCTORS FOR PCD . POWDER FORMING MACHINE ‘Single Crystal Diamond ‘Metric end mills、Miniature end mills、Специальные режущие инструменты ‘Пустотелое сверло ‘Pilot reamer、Fraises’Fresas con mango’ PCD (Polycrystalline diamond) ‘Frese’POWDER FORMING MACHINE’Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、Staple Cutter’PCD diamond cutter specialized in grooving floors’V-Cut PCD Circular Diamond Tipped Saw Blade with Indexable Insert’ PCD Diamond Tool’ Saw Blade with Indexable Insert’NAS tool、DIN or JIS tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills’end mill grinder’drill grinder’sharpener、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.
Bewise Inc. www.tool-tool.com
ようこそＢｅｗｉｓｅ Ｉｎｃ.の世界へお越し下さいませ、先ず御目出度たいのは新たな
情報を受け取って頂き、もっと各産業に競争力プラス展開。
弊社は専門なエンド・ミルの製造メーカーで、客先に色んな分野のニーズ、
豊富なパリエーションを満足させ、特にハイテク品質要求にサポート致します。
弊社は各領域に供給できる内容は：
（１）精密ＨＳＳエンド・ミルのＲ＆Ｄ
（２）Carbide Cutting tools設計
（３）鎢鋼エンド・ミル設計
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（５）超高硬度エンド・ミル
（６）ダイヤモンド・エンド・ミル
（７）医療用品エンド・ミル設計
（８）自動車部品＆材料加工向けエンド・ミル設計
弊社の製品の供給調達機能は：
（１）生活産業～ハイテク工業までのエンド・ミル設計
（２）ミクロ・エンド・ミル～大型エンド・ミル供給
（３）小Ｌｏｔ生産～大量発注対応供給
（４）オートメーション整備調達
（５）スポット対応～流れ生産対応
弊社の全般供給体制及び技術自慢の総合専門製造メーカーに貴方のご体験を御待ちしております。
Bewise
Inc. talaşlı imalat sanayinde en fazla kullanılan ve üç eksende (x,y,z)
talaş kaldırabilen freze takımlarından olan Parmak Freze imalatçısıdır.
Çok geniş ürün yelpazesine sahip olan firmanın başlıca ürünlerini
Karbür Parmak Frezeler, Kalıpçı Frezeleri, Kaba Talaş Frezeleri, Konik
Alın Frezeler, Köşe Radyüs Frezeler, İki Ağızlı Kısa ve Uzun Küresel
Frezeler, İç Bükey Frezeler vb. şeklinde sıralayabiliriz.
BW специализируется
в научных исследованиях и разработках, и снабжаем самым
высокотехнологичным карбидовым материалом для поставки режущих /
фрезеровочных инструментов для почвы, воздушного пространства и
электронной индустрии. В нашу основную продукцию входит твердый карбид /
быстрорежущая сталь, а также двигатели, микроэлектрические дрели, IC
картонорезальные машины, фрезы для гравирования, режущие пилы,
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для шлицевого вала / звездочки роликовой цепи, и специальные нано
инструменты. Пожалуйста, посетите сайт www.tool-tool.com для получения большей информации.
BW
is specialized in R&D and sourcing the most advanced carbide
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shaft/roller chain sprocket, and special tool, with nano grade. Please
visit our web www.tool-tool.com for more info.
