History of lithium discovery

Lithium is a metal element with the element symbol Li. The corresponding element is a silver white soft metal, which is also the metal with the lowest density. Used in atomic reactor, light alloy and battery. Lithium and its compounds are not as typical as other alkali metals, because lithium has a large charge density and a stable helium type double electron layer, which makes it easy to polarize other molecules or ions, but not itself. This affects the stability of it and its compounds.

As the electrode potential is the most negative, lithium is the most active metal among known elements (including radioactive elements).

In August, 2018, a team led by researchers from the National Astronomical Observatory of the Chinese Academy of Sciences found a strange celestial body relying on LAMOST. Its lithium content is about 3000 times that of similar celestial bodies, and it is the star with the highest Lithium Abundance known to mankind.

History of lithium discovery

The first lithium ore, lialsi4o10, was discovered by Brazilians on a Swedish island called ut ö in the 1890s. When thrown into the fire, it will emit a strong crimson flame. Johan August arfvedson of Stockholm analyzed it and concluded that it contained previously unknown metals. He called it lithium. He realized that this was a new alkali metal element. However, unlike sodium, he failed to separate it by electrolysis. In 1821, William Brande electrolyzed a small amount of lithium, but this was not enough for experiments. It was not until 1855 that the German chemist Robert Bunsen and the British chemist Augustus Matthiessen electrolyzed lithium chloride to obtain large blocks of lithium. Lithium in English is lithium, which comes from Greek LITHOS, meaning "stone". The first syllable of LITHOS is pronounced "Li". Because it is metal, add the radical "item" on the left. The content of lithium in the earth's crust is much less than that of potassium and sodium, and its compounds are rare, which is the inevitable factor that lithium was discovered later than potassium and sodium. In the second year of lithium discovery, it was re analyzed and confirmed by French chemist volkland.

Lithium, atomic number 3, atomic weight 6.941, is the lightest alkali metal element. The name of the element comes from Greek, which originally means "stone". In 1817, it was discovered by Swedish scientist ALF Weicong when he analyzed lithium feldspar ore. The main lithium minerals in nature are spodumene, lepidolite, lithiferous feldspar and aluminophosphate. Lithium can be found in human and animal bodies, soil and mineral water, cocoa powder, tobacco leaves and seaweed. There are two isotopes of natural lithium: lithium-6 and lithium-7.

Lithium metal is a silver white light metal; Melting point: 180.54 ° C, boiling point: 1342 ° C, density: 0.534 g / cm ³， Hardness 0.6. Lithium is soluble in liquid ammonia. Unlike other alkali metals, lithium reacts slowly with water at room temperature, but can react with nitrogen to form black lithium trinitride crystals. Weak salts of lithium are insoluble in water. Among alkali metal chlorides, only lithium chloride is easily soluble in organic solvents. The flame of the volatile salt of lithium is dark red, which can be used to identify lithium. Lithium is easily combined with oxygen, nitrogen and sulfur, and can be used as deoxidizer in metallurgical industry. Lithium can also be used as a component of lead based alloys and light alloys such as beryllium, magnesium and aluminum. Lithium has important applications in the atomic energy industry.

In August, 2018, a scientific research team led by the National Astronomical Observatory of the Chinese Academy of Sciences found a strange celestial body relying on the large scientific device GuoShouJing telescope (LAMOST). Its lithium content is about 3000 times that of similar celestial bodies, and its absolute Lithium Abundance is as high as 4.51, making it the star with the highest Lithium Abundance known to mankind. This important astronomical discovery was published online in the international scientific journal Nature astronomy in the early morning of August 7, Beijing time.

Lithium content distribution

In nature, it mainly exists in the form of spodumene, lepidolite and phosphorite.

The natural reserves of lithium in the earth's crust are 11million tons, and the recoverable reserves are 4.1 million tons. In 2004, the world lithium mining volume was 20200 tons, including 7990 tons in Chile, 3930 tons in Australia, 2630 tons in China, 2200 tons in Russia and 1970 tons in Argentina.

Lithium is known as a "rare metal". In fact, its content in the earth's crust is not "rare". There is about 0.0065% lithium in the earth's crust, and its abundance ranks 27th. More than 150 kinds of lithium bearing minerals are known, including spodumene, lepidolite and lithium permeable feldspar. The content of lithium in seawater is not small, with a total reserve of 260billion tons. Unfortunately, the concentration is too small to extract. Some mineral water and plant bodies are rich in lithium. For example, some red and yellow seaweeds and tobacco often contain more lithium compounds for development and utilization. China is rich in lithium mineral resources. Based on China's lithium salt output, only Jiangxi mica lithium mine can be mined for hundreds of years.