Lithium

Lithium (from Ancient Greek: λίθος, líthos, 'stone') is a chemical element; it has symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid element. Like all alkali metals, lithium is highly reactive and flammable, and must be stored in vacuum, inert atmosphere, or inert liquid such as purified kerosene or mineral oil.

Lithium does not occur freely in nature, but occurs mainly as pegmatitic minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride.

Lithium and its compounds have several industrial applications, including heat-resistant glass and ceramics, lithium grease lubricants, flux additives for iron, steel and aluminium production, lithium metal batteries, and lithium-ion batteries. Batteries alone consume more than three-quarters of lithium production. Lithium is also used in medicine; lithium-based drugs are useful as a mood stabilizer and antidepressant in the treatment of mental illness such as bipolar disorder.

Properties

The alkali metals are a group of elements, and lithium is the first one in this family. Like other alkali metals such as sodium and potassium, lithium has one outer electron that it can easily share, making it a good conductor of heat and electricity. Lithium is also very reactive, although it is less reactive than other alkali metals because its outer electron is closer to its center.

Lithium metal is soft and silvery-white, and it can even be cut with a knife. It is very light—it has the lowest density of all metals, which means it can float on water or very light oils. Lithium changes when exposed to air, turning into lithium oxide. It melts at a temperature of 180.50 °C and boils at a very high temperature of 1,342 °C, higher than any other alkali metal.

Lithium comes in two main forms found in nature, called isotopes: ⁶Li and ⁷Li. The latter is more common, making up about 95% of natural lithium. These isotopes behave differently in various natural processes, such as forming minerals or being used by living things. Scientists can separate these isotopes using special methods like laser technology.

Occurrence

Lithium-7 was created in the early moments of the universe in a process called Big Bang nucleosynthesis. It forms in small amounts compared to hydrogen and helium. Lithium can also be found in stars and brown dwarf objects. In cooler stars, lithium remains, but in hotter stars, it gets used up.

Lithium is found in small amounts in Earth's crust, water, and some minerals. It is most common in certain types of rocks like granites and in minerals such as spodumene and petalite. Chile has the largest known reserves of lithium, and Australia produces the most each year. Lithium is also present in very tiny amounts in plants, animals, and human bodies, though its role in living things is not fully understood.

History

Lithium was first discovered in 1800 by a chemist in Brazil, hidden inside a mineral called petalite found in Sweden. In 1817, another scientist found a new element inside this mineral, naming it lithium, which means “stone” in ancient Greek because it came from a rocky ore.

Later, scientists learned that lithium could change the color of fire to bright red and could be separated into a pure metal. In the 1940s and 1950s, doctors found that lithium could help people feeling very sad or excited, making them feel better. Today, lithium is very important for batteries in things like phones and cars.

Chemistry

Main page: Category:Lithium compounds

Main article: Organolithium reagent

Lithium is a soft, silvery-white metal that reacts with water to produce hydrogen gas and lithium hydroxide. When heated, lithium can give a beautiful red flame, and it can even catch fire when it meets water or air. To keep it safe, lithium is stored in special sealant like petroleum jelly.

Lithium mixes with many other elements to form useful compounds. One important compound is lithium carbonate, which comes from lithium ores and helps make batteries and ceramics. Lithium also forms special chemicals called organolithium compounds, which are very helpful for making medicines and other products in laboratories. These compounds are very reactive and can catch fire easily, so they need careful handling.

Production

See also: List of countries by lithium production

Lithium production has grown a lot since the end of World War II. The main sources of lithium are brines and ores.

Lithium metal is made through electrolysis of a mix of lithium chloride and potassium chloride at high temperatures.

Lithium is very important for batteries used in renewable energy, which means it will be in high demand. The small size of lithium atoms makes it hard to find in early mineral formations, but it ends up in molten phases where it becomes concentrated. The US Geological Survey estimated worldwide lithium reserves in 2022 and 2023 to be 26 million and 28 million tonnes, respectively.

The top lithium-producing countries in 2019 were Australia, Chile, China, and Argentina. The region known as the Lithium Triangle, which includes Chile, Bolivia, and Argentina, holds a large amount of lithium reserves. In the United States, lithium is also found in places like Nevada and California.

In 2021, much of the world’s lithium came from either spodumene, a mineral found in hard rock, or from salty brine pumped directly from the ground in places like Chile, Argentina, and Arkansas. In Chile’s Salar de Atacama, lithium is concentrated in brine by solar evaporation over a long period. New methods of Direct Lithium Extraction are being developed to make the process faster and use less land and water.

The manufacturing processes of lithium can harm the environment if not done carefully. It can pollute water, damage landscapes, and affect wildlife. In some places, lithium mining has led to conflicts with local communities over water use and other concerns.

Applications

Lithium is a very useful metal with many important uses. In 2021, about 87% of all lithium made was used to create lithium-ion batteries for electric cars and mobile devices. Lithium is great for batteries because it is very light and can carry a lot of power for its weight. Lithium-ion batteries can provide about 3 volts per cell, which is more than older types of batteries.

Lithium is also used to make special glass and ceramics. Adding lithium to glass makes it easier to melt and gives it useful properties, like resisting heat changes. Lithium is used in lubricating greases to help oils stay smooth even at high temperatures. It is also important in making metals stronger and lighter for airplane parts. In fireworks, lithium gives a beautiful red color. Lithium can help clean the air in spaceships and submarines by removing carbon dioxide. It is even used in some camera lenses and parts of mobile phones. In medicine, lithium helps treat certain mood disorders, though it must be used carefully.

Precautions

Lithium metal is corrosive and needs careful handling to prevent skin contact. Inhaling lithium dust or compounds can irritate the nose and throat, and in larger amounts, may cause fluid to build up in the lungs. The metal itself can be dangerous if it touches water, creating lithium hydroxide, a caustic substance. To keep it safe, lithium metal is stored in materials like naphtha that won’t react with it.