Rare earth elements are known as "industrial vitamins" and have irreplaceable excellent magnetic, optical, and electrical properties. They play a huge role in improving product performance, increasing product variety, and improving production efficiency. Due to its importanteffect and low usage, rare earths have become an important element in improving product structure, increasing technological content, and promoting industry technological progress. They are widely used in fields such as metallurgy, military, petrochemicals, glass ceramics, agriculture, and new materials.
metallurgical industry
Rare earths have been applied in the metallurgical field for more than 30 years, and have formed relatively mature technologies and processes. The application of rare earths in steel and non-ferrous metals is a large and wide-ranging field with broad prospects. The addition of rare earth metals, fluorides, and silicides to steel can play a role in refining, desulfurization, neutralizing low melting point harmful impurities, and improving the processing performance of steel; Rare earth silicon iron alloy and rare earth silicon magnesium alloy are used as spheroidizing agents to produce rare earth ductile iron. As this type of ductile iron is particularly suitable for producing complex ductile iron parts with special requirements, it is widely used in mechanical manufacturing industries such as automobiles, tractors, and diesel engines; The addition of rare earth metals to non-ferrous alloys such as magnesium, aluminum, copper, zinc, and nickel can improve the physical and chemical properties of the alloys, as well as enhance their room temperature and high-temperature mechanical properties.
Military field
Due to their excellent physical properties such as photoelectricity and magnetism, rare earths can form a variety of new materials with different properties and greatly improve the quality and performance of other products. Therefore, it is known as "industrial gold". Firstly, the addition of rare earths can significantly improve the tactical performance of steel, aluminum alloys, magnesium alloys, and titanium alloys used in the manufacturing of tanks, aircraft, and missiles. In addition, rare earths can also be used as lubricants in many high-tech fields such as electronics, lasers, nuclear industry, superconductivity, etc. Once rare earth technology is used in military, it will inevitably bring about a leap in military technology. In a certain sense, the overwhelming control of the US military in several local wars after the Cold War, as well as its ability to openly kill enemies without restraint, is due to its superiority in rare earth technology。
petrochemical industry
Rare earth elements can be used in the petrochemical industry to make molecular sieve catalysts, which have advantages such as high activity, good selectivity, and strong resistance to heavy metal poisoning. Therefore, they have replaced aluminum silicate catalysts in the petroleum catalytic cracking process; In the production process of synthetic ammonia, a small amount of rare earth nitrate is used as a co catalyst, and its gas processing capacity is 1.5 times larger than that of nickel aluminum catalyst; In the process of synthesizing butadiene rubber and isoprene rubber, the use of rare earth cycloalkanoate triisobutyl aluminum catalyst results in excellent product performance, with advantages such as less equipment adhesive hanging, stable operation, and short post-treatment process; Composite rare earth oxides can also be used as catalysts for exhaust gas purification in internal combustion engines, and cerium naphthenate can also be used as a paint drying agent.
Glass ceramics
The application of rare earth elements in China's glass and ceramic industry has increased at an average rate of 25% since 1988, reaching approximately 1600 tons in 1998. Rare earth glass and ceramics are not only traditional basic materials for industry and daily life, but also a major member of the high-tech field. Rare earth oxides or processed rare earth concentrates can be widely used as polishing powders for optical glass, eyeglass lenses, picture tubes, oscilloscope tubes, flat glass, plastics, and metal tableware; During the process of melting glass, cerium dioxide can be utilized to have a strong oxidizing effect on iron, reducing the iron content in the glass and achieving the goal of removing the green color from the glass; Adding rare earth oxides can produce optical glass and special glass for different purposes, including glass that can absorb infrared radiation, acid and heat resistant glass, X-ray resistant glass, etc; Adding rare earth elements to ceramic and porcelain glazes can reduce the fragmentation of the glaze and make the products present different colors and luster, making them widely used in the ceramic industry.
In terms of agriculture
The research results indicate that rare earth elements can increase the chlorophyll content of plants, enhance photosynthesis, promote root development, and increase nutrient absorption by roots. Rare earth elements can also promote seed germination, increase seed germination rate, and promote seedling growth. In addition to the main functions mentioned above, it also has the ability to enhance the disease resistance, cold resistance, and drought resistance of certain crops. Numerous studies have also shown that the use of appropriate concentrations of rare earth elements can promote the absorption, transformation, and utilization of nutrients by plants. Spraying rare earth elements can increase the Vc content, total sugar content, and sugar acid ratio of apple and citrus fruits, promoting fruit coloring and early ripening. And it can suppress the respiratory intensity during storage and reduce the decay rate.
New materials field
Rare earth neodymium iron boron permanent magnet materials, with high residual magnetism, high coercivity, and high magnetic energy product, are widely used in the electronics and aerospace industry, as well as driving wind turbines (especially suitable for offshore power plants); The single crystal and polycrystalline garnet type ferrite formed by the combination of pure rare earth oxides and ferric oxide can be used in the microwave and electronic industries; Yttrium aluminum garnet and neodymium glass made of high-purity neodymium oxide can be used as solid laser materials; Rare earth hexaborides can be used as cathode materials for electron emission; Lanthanum nickel metal is a newly developed hydrogen storage material in the 1970s; Lanthanum chromate is a high-temperature thermoelectric material; Superconducting materials made from barium based oxides improved by barium yttrium copper oxygen elements are currently used in various countries around the world, which can obtain superconductors in the liquid nitrogen temperature range, making breakthrough progress in the development of superconducting materials. In addition, rare earths are widely used in lighting sources such as fluorescent powder, intensifying screen fluorescent powder, tri color fluorescent powder, and photocopy lamp powder (but due to the rising cost of rare earths, their application in lighting is gradually decreasing), as well as electronic products such as projection TVs and tablets; In agriculture, applying trace amounts of rare earth nitrate to field crops can increase their yield by 5-10%; In the light textile industry, rare earth chlorides are also widely used in tanning fur, fur dyeing, yarn dyeing, and carpet dyeing; Rare earth elements can be used in automotive catalytic converters to convert major pollutants into non-toxic compounds during engine exhaust.
Other applications
Rare earth elements are also applied to various digital products, including audiovisual, photography, and communication devices, meeting multiple requirements such as smaller, faster, lighter, longer usage time, and energy efficiency. At the same time, it has also been applied in multiple fields such as green energy, healthcare, water purification, and transportation.
