Applications of rare earth
Rare earth element is known as the "industrial vitamin", with irreplaceable magnetic, optical and electrical properties, has played a huge role to improve product performance, increase product variety and improve production efficiency. Because rare earth has great effect and less dosage, has been the important element in improving the product structure, improve the content of science and technology, promote the industrial technological progress, is widely applied in the fields of metallurgy, military, petrochemical, agricultural, glass ceramics and new materials etc..
Rare earth has been used in the field of metallurgy for 30 years, has formed a relatively mature technology, the application of rare earth in iron and steel, nonferrous metals, is a large amount of wide field, has broad prospects. Rare earth metal silicide or fluoride, added to steel, to refining, desulfurization, can improve the processing performance of steel; rare earth ferrosilicon alloy, rare earth silicon magnesium alloy can be used to produce rare earth nodular cast iron as spheroidizing agent, nodular cast iron because this is particularly suitable for the production of special the complex requirements of nodular iron castings, are widely used in automobile, tractor, diesel engine and other mechanical manufacturing; rare earth metals are added to magnesium, aluminum, copper, zinc, nickel and other non-ferrous alloys, can improve physical and chemical properties of the alloys.
Due to the excellent physical and electrical properties, rare earth material can be used to improve the quality and performance of other products. Therefore, it is called "industrial gold". First of all, the addition of rare earth can greatly improve the tactical performance of steel, aluminum alloy, magnesium alloy and titanium alloy for the manufacture of tanks, aircraft and missiles. In addition, rare earth can also be used as high-tech lubricants in electronics, lasers, nuclear industry. Once the rare earth technology used in military, military science and technology will inevitably improve.
Rare earth can be used to make molecular sieve catalyst in petroleum and chemical industry, has many advantages such as high activity, good selectivity and strong resistance to heavy metal poisoning, which replaces the aluminum silicate catalyst used in petroleum catalytic cracking process; in the production of ammonia, nitric acid rare earth as a catalyst, the treatment capacity is 1.5 times of Ni Al catalyst; composite rare earth oxides can also be used as an internal combustion engine exhaust purification catalysts, cerium naphthenate is available as paint drying agent.
Rare earth glass ceramics is not only the basic material of industry and life, but also the main member of high-tech field. Rare earth oxide or rare earth concentrate can be used as a polishing powder after processing, is widely used in polishing of optical glass, glass sheet, tube, tube, plate glass, plastic and metal tableware; in the glass melting process, two cerium oxide has very strong oxidation of iron, in order to reduce iron content and achieve the purpose of removing green glass; rare earth oxides can be made of optical glass and special glass for different purposes, including through infrared, ultraviolet absorbing glass, heat resistant glass, anti acid and X- ray glass; rare earth in ceramic glaze and glaze, fragmentation can reduce the glaze, and can make the products show different color and luster, is widely used in ceramic industry.
Rare earth elements can improve the chlorophyll content of plants, enhance photosynthesis, promote root development, increase root absorption of nutrients. Rare earth can also promote seed germination, seed germination rate and seedling growth. In addition to the above main role, it has the ability to enhance the disease resistance, cold resistance and drought resistance of some crops. A large number of studies have shown that the use of appropriate concentrations of rare earth elements can promote the absorption, transformation and utilization of nutrients in plants. The Vc content, total sugar content and sugar acid ratio of apple and citrus fruits were increased by spraying rare earth. It can inhibit the respiration intensity and reduce the decay rate.
New material field
- NdFeB rare earth permanent magnetic materials, have many product characteristics such as high remanence, high coercivity and high energy, is widely used in electronic and aerospace industry and driving wind generator (especially for marine power plant); pure rare earth oxides and iron oxide into combinations of garnet single crystal and polycrystal, can be used in microwave with the electronics industry; made of high pure neodymium oxide and neodymium yttrium aluminum garnet glass, can be used as solid laser materials; rare earth boride six can be used for the production of cathode electron emission; lanthanum chromate is high temperature thermoelectric materials. In agriculture, rare earth nitrate is applied to field crops, the yield can increase 5~10%; in the textile industry, rare earth chloride is also widely used in tanning fur, fur dyeing, yarn dyeing and dyeing carpet etc.; rare earth is used in automotive catalytic converter, can change the main pollutants into nontoxic compounds in exhaust gas.
Rare earth elements have also been used in a wide variety of digital products, including audio-visual, photography, communications, a variety of digital devices, to meet the smaller, faster, lighter, longer use, energy saving and other requirements. At the same time, it has also been applied to many fields, such as green energy, medical treatment, water purification, transportation and so on.