A common metaphor is that if oil is the blood of industry, then rare earth is the vitamin of industry.
Rare earth is the abbreviation of a group of metals. Rare Earth Elements,REE) have been discovered one after another since the end of the 18th century. There are 17 kinds of REE, including 15 lanthanides in the periodic table of chemical elements-lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), and so onAt present, it has been widely used in many fields such as electronics, petrochemicals and metallurgy. Almost every 3-5 years, scientists can discover new uses of rare earth, and one out of every six inventions cannot be separated from rare earth.
China is rich in rare earth minerals, ranking first in three worlds: the first in resource reserves, accounting for about 23%; The output is the first, accounting for 80% to 90% of the world's rare earth commodities; Sales volume is the first, with 60% to 70% of rare earth products exported abroad. At the same time, China is the only country that can supply all 17 kinds of rare earth metals, especially medium and heavy rare earths with outstanding military use.China's share is enviable.
Rare earth is a valuable strategic resource, which is known as "industrial monosodium glutamate" and "mother of new materials", and is widely used in cutting-edge science and technology and military industry. According to the Ministry of Industry and Information Technology, functional materials such as rare earth permanent magnet, luminescence, hydrogen storage and catalysis have become indispensable raw materials for high-tech industries such as advanced equipment manufacturing, new energy and emerging industries.It is also widely used in electronics, petrochemical industry, metallurgy, machinery, new energy, light industry, environmental protection, agriculture and so on. .
As early as 1983, Japan introduced a strategic reserve system for rare minerals, and 83% of its domestic rare earths came from China.
Look at the United States again, its rare earth reserves are second only to China, but its rare earths are all light rare earths, which are divided into heavy rare earths and light rare earths. Heavy rare earths are very expensive, and light rare earths are uneconomical to mine, which has been turned into fake rare earths by people in the industry. 80% of US rare earth imports come from China.
Comrade Deng Xiaoping once said: "There is oil in the Middle East and rare earths in China." The implication of his words is self-evident. Rare earth is not only the necessary "MSG" for 1/5 high-tech products in the world, but also a powerful bargaining chip for China at the world negotiating table in the future. Protect and scientifically utilize rare earth resources,It has become a national strategy called for by many people with lofty ideals in recent years to prevent precious rare earth resources from being blindly sold and exported to western countries. In 1992, Deng Xiaoping clearly stated China's status as a big rare earth country.
List of uses of 17 rare earths
1. lanthanum is used in alloy materials and agricultural films
2.Cerium is widely used in automobile glass
3 praseodymium is widely used in ceramic pigments
4.Neodymium is widely used in aerospace materials
5 .Promethium provide auxiliary energy for satellites
6.Application of Samarium in Atomic Energy Reactor
7 Europium manufacturing lenses and liquid crystal displays
8.Gadolinium for medical magnetic resonance imaging
9.Terbium is used in aircraft wing regulator
10.Erbium is used in laser rangefinder in military affairs
11. Dysprosium is used as lighting source for film and printing
12 .Holmium is used to make optical communication devices
13 .Thulium is used for clinical diagnosis and treatment of tumors
14.Ytterbium additive for computer memory element
15.Application of lutetium in energy battery technology
16.Yttrium makes wires and aircraft force components
17.Scandium is often used to make alloys
The details are as follows:
1
Lanthanum (LA)
In the Gulf War, the night vision device with rare earth element lanthanum became the overwhelming source of US tanks.The above image shows lanthanum chloride powder（Data map)
Lanthanum is widely used in piezoelectric materials, electrothermal materials, thermoelectric materials, magnetoresistive materials, luminescent materials (blue powder), hydrogen storage materials, optical glass, laser materials, various alloy materials, etc. Lanthanum is also used in catalysts for the preparation of many organic chemical products,Scientists have named lanthanum "super calcium" for its effect on crops.
2
Cerium (CE)
Cerium can be used as catalyst, arc electrode and special glass.Cerium alloy is resistant to high heat and can be used to make jet propulsion parts（Data map)
(1) Cerium, as a glass additive, can absorb ultraviolet and infrared rays, and has been widely used in automobile glass.It can not only prevent ultraviolet rays, but also reduce the temperature inside the car, so as to save electricity for air conditioning.Since 1997, ceria has been added to all automotive glass in Japan. In 1996, at least 2000 tons of ceria were used in automobile glass, and more than 1000 tons in the United States.
(2) At present, cerium is being used in automobile exhaust purification catalyst, which can effectively prevent a large amount of automobile exhaust gas from being discharged into the air. The consumption of Cerium in the United States accounts for one third of the total consumption of rare earth.
(3) Cerium sulfide can be used in pigments instead of lead, cadmium and other metals which are harmful to the environment and human beings. It can be used to color plastics, coatings, ink and paper industries.At present, the leading company is French Rhone Planck.
(4) CE: LiSAF laser system is a solid-state laser developed by the United States. It can be used to detect biological weapons and medicine by monitoring tryptophan concentration.Cerium is widely used in many fields. Almost all rare earth applications contain cerium.Such as polishing powder, hydrogen storage materials, thermoelectric materials, cerium tungsten electrodes, ceramic capacitors, piezoelectric ceramics, cerium silicon carbide abrasives, fuel cell raw materials, gasoline catalysts, some permanent magnetic materials, various alloy steels and non-ferrous metals.
3
Praseodymium (PR)
(1) Praseodymium is widely used in building ceramics and daily-use ceramics. It can be mixed with ceramic glaze to make color glaze, and can also be used as underglaze pigment. The pigment is light yellow with pure and elegant color.
(2) It is used to manufacture permanent magnets.Using cheap praseodymium and neodymium metal instead of Pure Neodymium metal to make permanent magnet material, its oxygen resistance and mechanical properties are obviously improved, and it can be processed into magnets of various shapes.It is widely used in various electronic devices and motors.
(3) Used in petroleum catalytic cracking.The activity, selectivity and stability of the catalyst can be improved by adding the enriched praseodymium and neodymium into Y zeolite molecular sieve to prepare petroleum cracking catalyst.China began to put into industrial use in the 1970s, and the consumption is increasing.
(4) Praseodymium can also be used for abrasive polishing.In addition, praseodymium is widely used in optical fiber field.
4
Neodymium (nd)
Why can M1 tank be found first?The tank is equipped with a Nd: YAG laser rangefinder, which can reach a range of nearly 4000 meters in clear daylight（Data map)
With the birth of praseodymium, neodymium came into being. The arrival of neodymium activated the rare earth field, played an important role in the rare earth field, and influenced the rare earth market.
Neodymium has become a hot spot in the market for many years because of its unique position in the field of rare earths. The largest user of neodymium metal is NdFeB permanent magnet material. The advent of NdFeB permanent magnets has injected new vitality into the rare earth high-tech field. NdFeB magnet is called "the king of permanent magnets" because of its high magnetic energy product.It is widely used in electronics, machinery and other industries for its excellent performance. The successful development of Alpha Magnetic Spectrometer indicates that the magnetic properties of NdFeB magnets in China have entered the world-class level. Neodymium is also used in non-ferrous materials. Adding 1.5-2.5% neodymium into magnesium or aluminum alloy can improve the high temperature performance, air tightness and corrosion resistance of the alloy.Widely used as aerospace materials. In addition, neodymium-doped yttrium aluminum garnet produces short-wave laser beam, which is widely used in welding and cutting thin materials with thickness below 10mm in industry. In medical treatment, Nd: YAG laser is used to remove surgery or disinfect wounds instead of scalpel. Neodymium is also used for coloring glass and ceramic materials and as an additive for rubber products.
5
Promethium (Pm)
Promethium is an artificial radioactive element produced by nuclear reactors (data map)
(1) Can be used as a heat source. Provide auxiliary energy for vacuum detection and artificial satellite.
(2)Pm147 emits low-energy β-rays, which can be used to manufacture cymbal batteries. As the power supply of missile guidance instruments and clocks. This kind of battery is small in size and can be used continuously for several years. In addition, promethium is also used in portable X- ray instrument, preparation of phosphor, thickness measurement and beacon lamp.
6
Samarium (Sm)
Metal samarium (data map)
Sm is light yellow, and it is the raw material of Sm-Co permanent magnet, and Sm-Co magnet is the earliest rare earth magnet used in industry. There are two kinds of permanent magnets: SmCo5 system and Sm2Co17 system. In the early 1970s, the SmCo5 system was invented, and the Sm2Co17 system was invented in the later period. Now the demand of the latter is given priority to. The purity of samarium oxide used in samarium cobalt magnet need not be too high. Considering the cost,Mainly using about 95% of products. In addition, samarium oxide is also used in ceramic capacitors and catalysts. In addition, samarium has nuclear properties, which can be used as structural materials, shielding materials and control materials for atomic energy reactors, so that huge energy generated by nuclear fission can be used safely.
7
Europium (Eu)
Europium oxide powder (data map)
Europium oxide is mostly used for phosphors (data map)
In 1901, Eugene-AntoleDemarcay discovered a new element from "samarium", named Europium. This is probably named after the word Europe. Europium oxide is mostly used for fluorescent powder. Eu3+ is used as activator of red phosphor, and Eu2+ is used as blue phosphor. Now Y2O2S:Eu3+ is the best phosphor in luminous efficiency, coating stability and recycling cost.In addition, it is being widely used because of the improvement of technologies such as improving luminous efficiency and contrast. Europium oxide has also been used as stimulated emission phosphor for new X-ray medical diagnosis system in recent years. Europium oxide can also be used for manufacturing colored lenses and optical filters, for magnetic bubble storage devices,It can also show its talents in the control materials, shielding materials and structural materials of atomic reactors.
8
Gadolinium (Gd)
Gadolinium and its isotopes are the most effective neutron absorbers and can be used as inhibitors of nuclear reactors. (data map)
(1) Its water-soluble paramagnetic complex can improve the NMR imaging signal of human body in medical treatment.
(2) Its sulfur oxide can be used as matrix grid of oscilloscope tube and X-ray screen with special brightness.
(3) Gadolinium in Gadolinium Gallium Garnet is an ideal single substrate for bubble memory.
(4) It can be used as solid magnetic refrigeration medium without Camot cycle restriction.
(5) It is used as an inhibitor to control the chain reaction level of nuclear power plants to ensure the safety of nuclear reactions.
(6) It is used as an additive of samarium cobalt magnet to ensure that the performance does not change with temperature.
9
Terbium (Tb)
Terbium oxide powder (data map)
The application of terbium mostly involves the high-tech field, which is a cutting-edge project with technology-intensive and knowledge-intensive, as well as a project with remarkable economic benefits, with attractive development prospects.
(1) Phosphors are used as activators of green powder in tricolor phosphors, such as terbium-activated phosphate matrix, terbium-activated silicate matrix and terbium-activated cerium-magnesium aluminate matrix, which all emit green light in the excited state.
(2) Magneto-optical storage materials. In recent years, terbium magneto-optical materials have reached the scale of mass production. Magneto-optical discs made of Tb-Fe amorphous films are used as computer storage elements, and the storage capacity is increased by 10~15 times.
(3) Magneto-optical glass, terbium-containing Faraday rotatory glass is the key material for manufacturing rotators, isolators and annulators which are widely used in laser technology. Especially, the development of TerFenol has opened up a new application of Terfenol, which is a new material discovered in 1970s. Half of this alloy consists of terbium and dysprosium, sometimes with holmium and the rest is iron.The alloy was first developed by Ames Laboratory in Iowa, USA. When Terfenol is placed in a magnetic field, its size changes more than that of ordinary magnetic materials, which can make some precise mechanical movements possible. Terbium dysprosium iron is mainly used in sonar at first, and has been widely used in many fields at present.From fuel injection system, liquid valve control, micro-positioning, to mechanical actuators, mechanisms and wing regulators for aircraft space telescopes.
10
Dysprosium (Dy)
Metal dysprosium (data map)
(1) As an additive of NdFeB permanent magnets, adding about 2~3% dysprosium to this magnet can improve its coercive force. In the past, the demand for dysprosium was not large, but with the increasing demand of NdFeB magnets, it became a necessary additive element, and the grade must be about 95~99.9%, and the demand also increased rapidly.
(2) Dysprosium is used as the activator of phosphor. Trivalent dysprosium is a promising activating ion of tricolor luminescent materials with single luminescent center. It mainly consists of two emission bands, one is yellow light emission, the other is blue light emission. The luminescent materials doped with dysprosium can be used as tricolor phosphors.
(3) Dysprosium is a necessary metal raw material for preparing Terfenol alloy in magnetostrictive alloy, which can realize some precise activities of mechanical movement.
(4) Dysprosium metal can be used as magneto-optical storage material with high recording speed and reading sensitivity.
(5) Used in the preparation of dysprosium lamps, the working substance used in dysprosium lamps is dysprosium iodide, which has the advantages of high brightness, good color, high color temperature, small size, stable arc and so on, and has been used as lighting source for film and printing.
(6) Dysprosium is used to measure neutron energy spectrum or as neutron absorber in atomic energy industry because of its large neutron capture cross-sectional area.
(7)Dy3Al5O12 can also be used as magnetic working substance for magnetic refrigeration. With the development of science and technology, the application fields of dysprosium will be continuously expanded and extended.
11
Holmium (Ho)
Ho-Fe alloy (data map)
At present, the application field of iron needs to be further developed, and the consumption is not very large. Recently, the Rare Earth Research Institute of Baotou Steel has adopted high temperature and high vacuum distillation purification technology, and developed high purity metal Qin Ho/>RE>99.9% with low content of non-rare earth impurities.
At present, the main uses of locks are:
(1) As an additive of metal halogen lamp, metal halogen lamp is a kind of gas discharge lamp, which is developed on the basis of high-pressure mercury lamp, and its characteristic is that the bulb is filled with various rare earth halides. At present, rare earth iodides are mainly used, which emit different spectral lines when gas discharges. The working substance used in the iron lamp is qiniodide,Higher concentration of metal atoms can be obtained in the arc zone, thus greatly improving the radiation efficiency.
(2) Iron can be used as an additive for recording iron or billion aluminum garnet
(3) Khin-doped aluminum garnet (Ho: YAG) can emit 2um laser, and the absorption rate of 2um laser by human tissues is high, almost three orders of magnitude higher than that of Hd: YAG. Therefore, when using Ho: YAG laser for medical operation, it can not only improve the operation efficiency and accuracy, but also reduce the thermal damage area to a smaller size. The free beam generated by the lock crystal can eliminate fat without generating excessive heat,In order to reduce the thermal damage to healthy tissues, it is reported that w-laser treatment of glaucoma in the United States can reduce the pain of surgery.The level of 2um laser crystal in China has reached the international level, so it is necessary to develop and produce this kind of laser crystal.
(4) A small amount of Cr can also be added into the magnetostrictive alloy Terfenol-D to reduce the external field required for saturation magnetization.
(5) In addition, iron doped fiber can be used to make fiber laser, fiber amplifier, fiber sensor and other optical communication devices, which will play a more important role in today's rapid optical fiber communication
12
Erbium (ER)
Erbium oxide powder (information chart)
(1) The light emission of Er3 + at 1550nm is of special significance, because this wavelength is located at the lowest loss of optical fiber in optical fiber communication. After being excited by 980nm and 1480nm light, the bait ion (Er3 +) transits from the ground state 4115 / 2 to the high-energy state 4I13 / 2. When Er3 + in the high-energy state transitions back to the ground state, it emits 1550nm light. Quartz fiber can transmit light of different wavelengths,However, the optical attenuation rate of 1550nm band is the lowest (0.15 dB / km), which is almost the lower limit attenuation rate.Therefore, the optical loss of optical fiber communication is the minimum when it is used as signal light at 1550 nm.In this way, if the appropriate concentration of bait is mixed into the appropriate matrix, the amplifier can compensate the loss in the communication system according to the laser principle,Therefore, in the telecommunication network which needs to amplify the 1550nm optical signal, the bait doped fiber amplifier is an essential optical device. At present, the bait doped silica fiber amplifier has been commercialized.It is reported that in order to avoid useless absorption, the doped amount in optical fiber is tens to hundreds of ppm.The rapid development of optical fiber communication will open up new application fields.
(2) (2) In addition, the bait doped laser crystal and its output 1730nm laser and 1550nm laser are safe to human eyes, good atmospheric transmission performance, strong penetration ability to battlefield smoke, good security, not easy to be detected by the enemy, and the contrast of the radiation of military targets is large. It has been made into a portable laser rangefinder which is safe for human eyes in military use.
(3) (3) Er3 + can be added into glass to make rare earth glass laser material, which is the solid laser material with the largest output pulse energy and the highest output power.
(4) Er3 + can also be used as an active ion in rare earth upconversion laser materials.
(5) (5) In addition, the bait can also be used for decolorization and coloring of glasses glass and crystal glass.
13
Thulium (TM)
After being irradiated in a nuclear reactor, thulium produces an isotope that can emit X-ray, which can be used as a portable X-ray source（Data map)
(1) Thulium is used as the ray source of portable X-ray machine. After being irradiated in nuclear reactor, TM produces a kind of isotope which can emit X-ray, which can be used to make portable blood irradiator. This kind of radiometer can change yu-169 into TM-170 under the action of high and middle beam, and radiate X-ray to irradiate blood and decrease white blood cells. It is these white blood cells that cause rejection of organ transplantation,So as to reduce the early rejection of organs.
(2) (2) Thulium can also be used in clinical diagnosis and treatment of tumor because of its high affinity for tumor tissue, heavy rare earth is more compatible than light rare earth, especially the affinity of Yu is the largest.
(3) (3) The X-ray sensitizer Laobr: br (blue) is used as activator in the phosphor of X-ray sensitization screen to enhance the optical sensitivity, thus reducing the exposure and harm of X-ray to human beings×The radiation dose is 50%, which has important practical significance in medical application.
(4) (4) The metal halide lamp can be used as additive in new lighting source.
(5) (5) Tm3 + can be added into glass to make rare earth glass laser material, which is the solid-state laser material with the largest output pulse and the highest output power.Tm3 + can also be used as the activation ion of rare earth upconversion laser materials.
14
Ytterbium (Yb)
Ytterbium metal (data map)
(1) As thermal shielding coating material.The results show that mirror can improve the corrosion resistance of electrodeposited zinc coating obviously, and the grain size of coating with mirror is smaller than that of coating without mirror.
(2) As magnetostrictive material.This material has the characteristics of giant magnetostriction, that is, expansion in magnetic field.The alloy is mainly composed of mirror / ferrite alloy and dysprosium / ferrite alloy, and a certain proportion of manganese is added to produce giant magnetostriction.
(3) Mirror element used for pressure measurement. Experiments show that the sensitivity of the mirror element is high in the calibrated pressure range, which opens up a new way for the application of the mirror in pressure measurement.
(4) Resin-based fillings for cavities of molars to replace silver amalgam commonly used in the past.
(5) Japanese scholars have successfully completed the preparation of mirror-doped vanadium baht garnet embedded line waveguide laser, which is of great significance to the further development of laser technology. In addition, the mirror is also used for fluorescent powder activator, radio ceramics, electronic computer memory element (magnetic bubble) additive, glass fiber flux and optical glass additive, etc.
15
Lutetium (Lu)
Lutetium oxide powder (data map)
Yttrium lutetium silicate crystal (data map)
(1) make some special alloys. For example, lutetium aluminum alloy can be used for neutron activation analysis.
(2) Stable lutetium nuclides play a catalytic role in petroleum cracking, alkylation, hydrogenation and polymerization.
(3) The addition of yttrium iron or yttrium aluminum garnet can improve some properties.
(4) Raw materials of magnetic bubble reservoir.
(5) A composite functional crystal, lutetium-doped aluminum yttrium neodymium tetraborate, belongs to the technical field of salt solution cooling crystal growth. Experiments show that lutetium-doped NYAB crystal is superior to NYAB crystal in optical uniformity and laser performance.
(6) It has been found that lutetium has potential applications in electrochromic display and low-dimensional molecular semiconductors. In addition, lutetium is also used in energy battery technology and activator of phosphor.
16
Yttrium (y)
Yttrium is widely used, yttrium aluminum garnet can be used as laser material, yttrium iron garnet is used for microwave technology and acoustic energy transfer, and europium-doped yttrium vanadate and europium-doped yttrium oxide are used as phosphors for color TV sets. (data map)
(1) Additives for steel and non-ferrous alloys. FeCr alloy usually contains 0.5-4% yttrium, which can enhance the oxidation resistance and ductility of these stainless steels; The comprehensive properties of MB26 alloy are obviously improved by adding a proper amount of yttrium-rich mixed rare earth, which can replace some medium-strong aluminum alloys and be used in the stressed components of aircraft. Adding a small amount of yttrium-rich rare earth into Al-Zr alloy,The conductivity of that alloy can be improve; The alloy has been adopted by most wire factories in China. Adding yttrium into copper alloy improves conductivity and mechanical strength.
(2) Silicon nitride ceramic material containing 6% yttrium and 2% aluminum can be used to develop engine parts.
(3) The Nd: Y: Al: Garnet laser beam with power of 400 watts is used to drill, cut and weld large components.
(4) The electron microscope screen composed of Y-Al garnet single crystal has high fluorescence brightness, low absorption of scattered light, and good high temperature resistance and mechanical wear resistance.
(5) High yttrium structural alloy containing 90% yttrium can be used in aviation and other places requiring low density and high melting point.
(6) Yttrium-doped SrZrO3 high-temperature proton conductive material, which attracts much attention at present, is of great significance to the production of fuel cells, electrolytic cells and gas sensors requiring high hydrogen solubility. In addition, yttrium is also used as a high-temperature spraying material, a diluent for atomic reactor fuel, an additive for permanent magnetic materials, and a getter in the electronics industry.
17
Scandium (Sc)
Metal scandium (data map)
Compared with yttrium and lanthanide elements, scandium has a particularly small ionic radius and a particularly weak alkalinity of hydroxide. Therefore, when scandium and rare earth elements are mixed together, scandium will precipitate first when treated with ammonia (or extremely dilute alkali), so it can be easily separated from rare earth elements by the method of "fractional precipitation". Another method is to use the polarization decomposition of nitrate for separation.Scandium nitrate is the easiest to decompose, thus achieving the purpose of separation.
Sc can be obtained by electrolysis. ScCl3, KCl and LiCl are co-melted during scandium refining, and the molten zinc is used as cathode for electrolysis, so that scandium is precipitated on the zinc electrode, and then the zinc is evaporated to obtain scandium. In addition, scandium is easily recovered when processing ore to produce uranium, thorium and lanthanide elements. Comprehensive recovery of associated scandium from tungsten and tin ore is also one of the important sources of scandium.Scandium is mainly in trivalent state in the compound, which is easily oxidized into Sc2O3 in air and loses its metallic luster and turns into dark gray.
The main uses of scandium are:
(1) Scandium can react with hot water to release hydrogen, and is also soluble in acid, so it is a strong reducing agent.
(2) Scandium oxide and hydroxide are only alkaline, but its salt ash can hardly be hydrolyzed. Scandium chloride is white crystal, soluble in water and deliquescent in air.
(3) In metallurgical industry, scandium is often used to make alloys (additives of alloys) to improve the strength, hardness, heat resistance and performance of alloys. For example, adding a small amount of scandium to molten iron can significantly improve the properties of cast iron, while adding a small amount of scandium to aluminum can improve its strength and heat resistance.
(4) In the electronic industry, scandium can be used as various semiconductor devices. For example, the application of scandium sulfite in semiconductors has attracted attention at home and abroad, and the ferrite containing scandium is also promising in computer magnetic cores.
(5) In the chemical industry, scandium compound is used as an alcohol dehydrogenation and dehydration agent, which is an efficient catalyst for the production of ethylene and chlorine from waste hydrochloric acid.
(6) In the glass industry, special glasses containing scandium can be manufactured.
(7) In the electric light source industry, scandium and sodium lamps made of scandium and sodium have the advantages of high efficiency and positive light color.
(8) Scandium exists in the form of 45Sc in nature. In addition, there are nine radioactive isotopes of Scandium, namely 40~44Sc and 46~49Sc. Among them, 46Sc, as a tracer, has been used in chemical industry, metallurgy and oceanography. In medicine, there are people abroad who study using 46Sc to treat cancer.
Post time: Aug-09-2021