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Lithium 101
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Useful Conversions |
The most commonly used unit for lithium production from brines is tonnes of lithium carbonate (Li2CO3) or lithium carbonate equivalent ("LCE").
One tonne of LCE contains 0.1879 tonnes lithium metal.
One tonne lithium metal is contained in 5.322 tonnes LCE.
The most commonly used unit for lithium production from hard rock sources is tonnes of lithium oxide (Li2O).
One tonne of lithium oxide contains 0.4646 tonnes lithium metal.
One tonne of lithium metal is contained in 2.1525 tonnes lithium oxide. |
General Lithium Information
| Lithium is the lightest metal and the least dense solid element. It is widely distributed on Earth, however due to its high reactivity it appears naturally only in the form of compounds. Lithium metal is flammable and potentially explosive when exposed to air and especially water, though it is far less reactive than other alkali metals in this regard. When placed over a flame, lithium gives off a crimson color, but when it burns strongly, the flame becomes a brilliant white. Lithium will ignite and burn in oxygen when exposed to water or water vapours. Due to its reactive nature, lithium metal tarnishes rapidly in moist air 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). | |  |
Lithium occurs in a number of pegmatitic minerals, brines and clays. Estimates for crustal content range from 20 to 70 ppm by weight. Seawater contains an estimated 230 billion tons of lithium, though at a low concentration of 0.1 to 0.2 ppm.
Lithium in brines are derived mainly from the leaching of volcanic rocks. These vary greatly in lithium content from between 30 to 60 ppm in the Great Salt Lake, Utah, through the subsurface brines in Searles Lake California (a former location of lithium production) and Silver Peak, Nevada (a current source) to the high altitude salars in Bolivia, Argentina, Chile, Tibet and China where lithium concentrations can be very high. Geothermal brines. The most attractive known occurrences of geothermal brines are in the the Brawley area south of the Salton Sea in Southern California. Known sources of oilfield brines occur in North Dakota, Wyoming, Oklahoma, east Texas and Arkansas where brines grade up to 700mg/lt. Channel Resources is assessing oilfield brine occurrences in Alberta, Canada.
Pegmatites are course grained igneous rocks formed by the crystallization of post magmatic fluids. They occur in close proximity to large magmatic intrusions. The principal lithium pegmatite minerals are spodumene, petalite (both lithium-aluminium silicates) and lepidolite (a lithium mica) which normally contains minor quantities of cesium, rubidium and fluorine.
Hectorite is a magnesium lithium smectite and the clay is found in a number of areas in the western United States. The largest known deposit is associated with the volcanic rocks of the McDermitt caldera that straddles the Nevada/Oregon border where it occurs in a series of elongate lenses.
Production
Since the end of World War II, lithium metal production has greatly increased. The metal is separated from other elements in igneous minerals, and lithium salts are extracted from the water of mineral springs, brine pools, and brine deposits.
Chile is currently the leading lithium metal producer in the world, followed by Argentina. Both countries recover the lithium from brine pools. In the United States lithium is similarly recovered from brine pools in Nevada. It is considered that the largest, as yet undeveloped, brine deposit is located in the Uyuni Desert of Bolivia, which according to the US Geological Survey hosts 5.4 million tons of lithium.
China is also emerging as a producer of brine-based lithium carbonate. Potential capacity of up to 55,000 tonnes per year is estimated from as projects in Qinghai province and Tibet.
The total amount of lithium recoverable from global reserves has been estimated at 35 million tonnes, which includes 15 million tonnes of the known global lithium reserve base.
Lithium Applications
Batteries |
- Lithium batteries are disposable (primary) batteries that have lithium metal or lithium compounds as an anode.
- Lithium-ion batteries are high energy-density rechargeable batteries. Their high electrochemical potential allows a typical cell to generate approximately 3 Volts (cf. 1.5 volts for Lead/Acid or Zinc cells); additionally its low atomic mass gives a high charge (and power) to weight ratio.
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Telecommunications |
- Lithium niobate is used extensively in telecommunication products, such as mobile phones and optical modulators, for such components as resonant crystals. Lithium products are currently used in more than 60 percent of mobile phones.
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Chemicals |
- Lithium chloride and lithium bromide are extremely hygroscopic (absorbs water) and are used as desiccants.
- Lithium metal is used in the preparation of organo-lithium compounds.
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Medical and Pharmaceutical |
- Lithium is 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.
- Organolithiums are also used in polymer synthesis, as catalysts/initiators in anionic polymerisation of unfunctionalised olefins.
- Lithium salts such as lithium carbonate (Li2CO3), lithium citrate, and lithium orotate are mood stabilizers.
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Optics |
- Lithium is used in glasses and ceramics including the glass for the 200-inch (5.08 m) telescope at Mt. Palomar.
- The high non-linearity of lithium niobate is applied non-linear optics.
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Rocketry |
- Metallic lithium and its complex hydrides such as e.g. Li[AlH4] are considered as high energy additives to rocket propellants.
- Lithium peroxide, lithium nitrate, lithium chlorate and lithium perchlorate are used as oxidizers in rocket propellants
- 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, which generates enormous quantities of heat, in turn used to generate steam from seawater. The steam propels the torpedo in a closed Rankine cycle.
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Nuclear applications |
- Lithium deuteride was used as a fusion fuel 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.
- Lithium fluoride (highly enriched in the common isotope lithium-7) forms the basic constituent of the fluoride salt mixture (LiF-BeF2) used in liquid-fluoride nuclear reactors. Lithium fluoride is chemically stable and LiF/BeF2 mixtures have low melting points and the best neutronic properties of fluoride salt combinations appropriate for reactor use.
- Lithium will be used to produce tritium in magnetically confined nuclear fusion 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 + 3H. Various means of doing this will be tested at the ITER reactor being built at Cadarache, France.
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Other uses |
- 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 lithium soap. Lithium soap has the ability to thicken oils and is used commercially to manufacture lubricating greases.
- Lithium hydroxide and lithium peroxide are used in confined areas, such as aboard spacecraft and submarines for air purification. Lithium hydroxide absorbs the carbon dioxide from the air by reacting with it to form lithium carbonate, being prefered over other alkaline hydroxides for its low weight.
- Lithium peroxide (Li2O2) in the presence of moisture not only absorbs carbon dioxide to form lithium carbonate, but also releases oxygen. E.g. 2 Li2O2 + 2 CO2 → 2 Li2CO3 + O2.
- Lithium compounds can be used to make red fireworks and flares.
- Because of its specific heat capacity, the highest of all solids, lithium is often used in heat transfer applications.
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From Wikipedia and other sources