Lithium (LI) is a silvery white metal element. It is soft and the least dense metal. It is used in atomic reactors, light alloys and batteries. 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 lithium easy to polarize other molecules or ions, but not itself. This affects the stability of it and its compounds.

Since the electrode potential is the most negative, lithium is the most active metal among known elements (including radioactive elements) (note that it is not metallic, and cesium is the most metallic among known 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, which is the star with the highest Lithium Abundance known to mankind.

Discovery history

The first lithium ore, lialsi ? o ?, was discovered by the Brazilian (joz é bonif á CIO de andralda e Silva) on a Swedish island called ut ? 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 the 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 affirmed by French chemist volkland.

 Content distribution

In nature, it mainly exists in the form of spodumene, lepidolite and phosphoaluminite. The natural reserves of lithium in the earth's crust are 11 million tons and the exploitable reserves are 4.1 million tons. In 2004, the world's 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 minerals containing lithium are known, including spodumene, lepidolite, lithium permeable feldspar and so on. The content of lithium in seawater is not small, with a total reserves of 260 billion tons. Unfortunately, the concentration is too small, so it is difficult to extract. Some mineral water and plant bodies are rich in lithium. For example, some red and yellow algae 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, Jiangxi mica lithium mine alone can be mined for hundreds of years.

 Preparation method

In 1855, Bunsen and machison produced lithium chloride by electrolytic melting. The industrial production of lithium was proposed by Gensha in 1893. It took 76 years from being recognized as an element to before and after industrial production. The production of lithium by electrolysis of lithium chloride consumes a lot of electric energy. For each ton of lithium, the power consumption is as high as 60000 to 70000 degrees.

In industry, lithium can be prepared by the following methods: burning and drying lithium chloride at a temperature not exceeding its melting point (602 ℃) for 1H. The above lithium chloride is dissolved in freshly distilled pyridine dehydrated and dried by potassium hydroxide to prepare a pyridine solution of 11.81% lithium chloride as electrolyte. Graphite plate is used as anode and bright and clean platinum sheet or iron sheet is used as cathode without diaphragm. The voltage used in electrolysis is 1.4V and the current density is 0.2 ~ 0.3a/100c ㎡.

Main distribution of lithium resources

Global lithium resources are mainly concentrated in Australia and South America. Chile accounts for about 44%, Australia for about 22%, Argentina for about 9%, China for about 7% and the United States for about 4%.

According to Everbright's materials, as shown in the figure: Australia and Chile together supply more than 70% of lithium production to the world.

At present, China's consumption of lithium accounts for more than 50% of the world, South Korea's lithium consumption accounts for about 20%, and Japan's lithium consumption accounts for about 12%. However, China is currently the largest consumer of lithium from the demand for electric vehicles, energy storage and 3C (computer, communication and consumer electronic products) driven by carbon peak carbon neutralization.

However, the output of lithium energy accounts for only 17% of the global supply, so most lithium mineral resources need to be imported from the outside. According to the data of Everbright, in 2020, the external dependence of lithium raw materials accounted for nearly 70.5%.

Main purpose

Tritium can be obtained by placing the isotope (6Li) with mass number 6 in an atomic reactor and irradiating it with neutrons. Tritium can be used for thermonuclear reaction and has important applications. Lithium is mainly used as thickener of lubricating grease in the form of lithium stearate. This lubricant has high water resistance, high temperature resistance and good low temperature performance. Lithium compounds are used in ceramic products to act as cosolvent. It is also used as deoxidizer or dechlorinating agent in metallurgical industry and lead based bearing alloy. Lithium is also an important component of beryllium, magnesium and aluminum light alloys.

Lithium is closely related to daily life. Lithium ion batteries used in personal laptop computers, mobile phones, Bluetooth headsets and other digital products contain rich lithium elements. Lithium ion battery is a high-energy storage medium. Due to the rapid development of lithium ion battery, the business of lithium ore, lithium carbonate and other companies has developed vigorously. Lithium metal batteries are also used in military fields.

Lithium has been neglected for quite a long time after its discovery. Only a few lithium compounds have been used in glass, ceramics and lubricants.

The main industrial use of lithium in the past was as thickener of lubricant in the form of lithium stearate. Lithium based grease has high water resistance, high temperature resistance and good low temperature performance. If you add lithium lubricant to some parts of the car once, it will be enough until the car is scrapped.

In metallurgical industry, lithium can strongly react with oxygen, nitrogen, chlorine, sulfur and other substances to act as deoxidizer and desulfurizer. In the process of copper smelting, adding 1 / 100000 to 1 / 10000 lithium can improve the internal structure of copper and make it more dense, so as to improve the conductivity of copper. Lithium can remove harmful impurities and gases in high-quality copper castings. It is the most ideal material to remove impurities in modern steel.

1kg lithium can release 42998kj of heat after combustion, so lithium is one of the best metals used as rocket fuel. The energy released by 1kg lithium through thermonuclear reaction is equivalent to the combustion of more than 20000 tons of high-quality coal. If lithium or lithium compounds are used to make solid fuel instead of solid propellant and used as the driving force of rockets, missiles and spacecraft, it not only has high energy, high burning rate, but also has very high specific impulse. The payload of the rocket directly depends on the specific impulse.

If lithium is added to glass manufacturing, the solubility of Lithium glass is only 1 / 100 of that of ordinary glass (about one tenth of a gram of glass in each ordinary glass of hot tea). After adding lithium, the glass becomes "insoluble" and can resist acid corrosion.

Pure aluminum is too soft. When a small amount of lithium, magnesium, beryllium and other metals are added to aluminum to melt into an alloy, it is light and especially hard. Using this alloy to make an aircraft can reduce the weight of the aircraft by 2 / 3. A lithium aircraft can be carried by two people. Lithium lead alloy is a good antifriction material.

It was after the discovery of its excellent nuclear properties that lithium really became a world-renowned metal. Because of its unique properties in the atomic energy industry, it is called "high-energy metal".

Lithium battery is a high-quality energy developed in the 1930s and 1940s. It has been widely used in various fields and is a promising power battery with the advantages of high open circuit voltage, high specific energy, wide working temperature range, discharge balance and self discharge electronics. Using lithium battery to generate electricity to drive a car, the driving cost is only 1 / 3 of that of an ordinary gasoline engine car. Tritium is produced from lithium and used to start the atomic battery pack. It does not need to be charged in the middle and can work continuously for 20 years. One of the important ways to solve the automobile oil crisis and exhaust pollution is to develop new batteries such as lithium batteries.

One of the important uses of lithium compounds in the past is in ceramic products, especially in enamel products. The main function of lithium compounds is as flux.

Lithium fluoride is extremely transparent to ultraviolet light. The glass made of it can gain insight into the mysteries hidden in the deepest part of the Milky Way galaxy. Lithium glass can be used to make TV picture tubes.

During World War II, American pilots were equipped with a portable emergency hydrogen source - lithium hydride pill. When the plane crashed and fell on the water, as soon as it touched the water, lithium hydride dissolved immediately and released a large amount of hydrogen to inflate and expand the life-saving equipment

Lithium deuterate and lithium tritium are used to replace deuterium and tritium, which are installed in the hydrogen bomb as explosives to achieve the purpose of hydrogen bomb explosion. Lithium deuteride was used in the first hydrogen bomb that China successfully exploded on June 17, 1967.

Lithium borohydride and lithium aluminum hydride are widely used as reducing agents in organic chemical reactions. Lithium borohydride can reduce aldehydes, ketones and esters. Lithium aluminum hydride is an important reducing agent in the preparation of drugs, spices and fine organic chemicals. Lithium aluminum hydride can also be used as jet fuel. Lithium aluminum hydride is a strong reducing agent for special bonding of complex molecules. This reagent has become an important reagent in many organic synthesis.

Organic lithium compounds react with organic acids to obtain an addition product that can be hydrolyzed to ketones. This reaction is used in one step of vitamin a synthesis. Organic lithium compounds are added to aldehydes and ketones to obtain addition products that can produce alcohols during hydrolysis.

The amino lithium prepared by the reaction of lithium and ammonia is used to introduce amino groups and is also used as dehalogenation reagent and catalyst.

Article source: carbon neutral new energy, my financial circle

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