Rare earth elements are known as “industrial vitamins”. They have excellent magnetic, optical and electrical properties that cannot be replaced. They have played a huge role in improving product performance, increasing product varieties, and increasing production efficiency. Due to its large effect and small amount, rare earth has become an important element to improve product structure, increase scientific and technological content, and promote technological progress in the industry. It has been widely used in metallurgy, military, petrochemical, glass ceramics, agriculture and new materials.
Rare earths have been applied in the metallurgical field for more than 30 years. At present, relatively mature technologies and processes have been formed. The application of rare earths in iron and steel and non-ferrous metals is a large-scale and wide-ranging field with broad prospects. Rare earth metals or fluorides and silicides added to steel can play a role in refining, desulfurizing, neutralizing low melting point harmful impurities, and can improve the processing performance of steel; rare earth ferrosilicon alloy and rare earth silicon-magnesium alloy are used as spheroidizing agent to produce rare earth Ductile iron, because this type of ductile iron is particularly suitable for the production of complex ductile iron parts with special requirements, it is widely used in machinery manufacturing such as automobiles, tractors, and diesel engines; rare earth metals are added to non-ferrous metals such as magnesium, aluminum, copper, zinc, and nickel In the alloy, the physical and chemical properties of the alloy can be improved, and the room temperature and high temperature mechanical properties of the alloy can be improved.
Because rare earth has excellent physical properties such as photoelectromagnetism, it can form a wide variety of new materials with different properties and other materials, which can greatly improve the quality and performance of other products. Therefore it is called “industrial gold”. First of all, the addition of rare earths can greatly improve the tactical performance of steel, aluminum alloys, magnesium alloys, and titanium alloys used in the manufacture of tanks, aircraft, and missiles. In addition, rare earths can also be used as high-tech lubricants in electronics, lasers, nuclear industry, superconductivity, and many more. Once rare earth technology is used in the 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 and its ability to openly kill the enemy unscrupulously stemmed from its superior rare earth technology.
Rare earth can be used to make molecular sieve catalysts in the petrochemical industry. It has the advantages of high activity, good selectivity, and strong resistance to heavy metal poisoning. Therefore, it replaces aluminum silicate catalysts for petroleum catalytic cracking process; in the production process of synthetic ammonia, it is used A small amount of rare earth nitrate is used as a co-catalyst, and its processing gas volume is 1.5 times larger than that of the nickel-aluminum catalyst; in the process of synthesizing butadiene rubber and isoprene rubber, the naphthenate-triisobutyl aluminum catalyst is used to obtain the product performance Excellent, with less glue on equipment, stable operation, short post-treatment process, etc.; composite rare earth oxide can also be used as a catalyst for exhaust gas purification of internal combustion engines, and cerium naphthenate can also be used as a paint drier.
The application of rare earths in my country’s glass and ceramics industry has been increasing at an average rate of 25% since 1988, reaching about 1,600 tons in 1998. Rare earth glass ceramics are not only traditional basic materials for industry and life, but also major members in the high-tech field. . Rare earth oxides or processed rare earth concentrates can be widely used as polishing powder for polishing optical glass, spectacle lenses, picture tubes, oscilloscope tubes, flat glass, plastics and metal tableware; it can be used in the glass melting process Cerium dioxide has a strong oxidizing effect on iron, reducing the iron content in the glass to achieve the purpose of removing the green in the glass; adding rare earth oxides can make optical glasses and special glasses for different purposes, including the ability to pass infrared rays , UV-absorbing glass, acid-resistant and heat-resistant glass, X-ray resistant glass, etc.; adding rare earths to ceramic glazes and enamels can reduce the fragmentation of the glaze, and make the products show different colors and glosses. It is widely used in the ceramic industry.
The research results show that rare earth elements can increase the chlorophyll content of plants, enhance photosynthesis, promote root development, and increase roots’ absorption of nutrients. Rare earth can also promote seed germination, increase seed germination rate, and promote seedling growth. In addition to the above main functions, it also has the ability to enhance disease resistance, cold resistance and drought resistance of certain crops. A large number of 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 earths can increase the Vc content, total sugar content, sugar-acid ratio of apple and citrus fruits, and promote fruit coloring and early maturity. It can also inhibit the breathing intensity during storage and reduce the decay rate.
New material field
The rare earth neodymium iron boron permanent magnet material has the characteristics of high remanence, high coercivity and high magnetic energy product. It is widely used in the electronics and aerospace industry and to drive wind generators (especially suitable for offshore power plants); pure rare earth oxides and The garnet-type ferrite single crystal and polycrystalline formed by the combination of iron 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 hexaboron Compounds can be used to make 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; current countries around the world use barium-yttrium-copper-oxygen modified barium-based oxides Conductive materials, superconductors can be obtained in the temperature zone of liquid nitrogen, making a breakthrough in the development of superconducting materials. In addition, rare earths are also widely used in lighting sources such as phosphors, intensifying screen phosphors, tri-color phosphors, copy lamp powders, etc. (but due to rising prices of rare earths leading to higher costs, the application in lighting is gradually decreasing), Electronic products such as projection TVs, tablet computers, etc.; in agriculture, the application of trace amounts of rare earth nitrate to field crops can increase their output by 5-10%; in the textile industry, rare earth chlorides are also widely used in fur tanning, fur dyeing, Wool dyeing and carpet dyeing; rare earths are used in automotive catalytic converters to convert the main pollutants into non-toxic compounds when the engine exhausts.
Rare earth elements are also used in a variety of digital products including audio-visual, photography, and communication digital equipment, which meets the requirements of smaller, faster, lighter, longer-lasting, and energy-saving products. At the same time, it has also been applied to many fields such as green energy, medical treatment, water purification, and transportation.