Department of Commerce: China's rare earth resources is only for 20 years, rare earth lanthanide elements in the periodic table - lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), Promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), as well as the 15 lanthanide elements are closely related to two elements - scandium (Sc) and yttrium (Y) a total of 17 elements, known as the REE (Rare Earth). Referred to as the rare earth (RE or R). RE
term historical name. Rare earth elements from the late 18th century began to discover, when people often do not dissolve in water, solid oxide called soil. Oxides of the general state of soil is separated out, and very rare, and thus was named earth. Usually lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium or cerium rare earth group known as the light rare earth; to gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium yttrium rare earth or yttrium group known as the heavy rare earths. Rare earth elements and some physical and chemical properties based on the similarities and differences, in addition to outside scandium (Sc, some will be placed under the scattered elements), divided into three groups, namely, light rare earth group, lanthanum, cerium, praseodymium, neodymium, promethium; group of rare earth samarium, europium, gadolinium, terbium, dysprosium; heavy rare earth group, holmium, erbium, thulium, ytterbium, lutetium, yttrium.
Japan is a major user of rare earth, the current number of China's exports of rare earth rare earth in the world and many major weapons systems as the key material, almost all of the United States to be imported from China. Rare is the most abundant strategic resources, it is essential to many sophisticated industrial raw materials, China has a lot of strategic resources such as iron ore and other poor, but is very rich in rare earth resources. At present, resources are precious wealth of a country, but also to safeguard their own rights and interests of developing countries, the importance of power against power weapons. The chief architect of China's reform and opening up, Comrade Deng Xiaoping once said meaningfully: its excellent physical properties of light and electromagnetic, properties of material composition can be varied with other, a wide variety of new materials, its most notable feature is the substantial increase in the quality and performance of other products. Such as the substantial increase for the manufacture of tanks, aircraft, missiles of steel, aluminum, magnesium alloy, titanium and tactical performance. Moreover, the rare earth is also electronic, laser, nuclear industry, superconductivity, and many other high-tech lubricants. Earth science and technology once used for military, inevitably bring about a leap in military technology. In a sense, the U.S. military after the Cold War times overwhelming control of local war, and the ability to openly and blatantly killing the enemy, is due to the superior adult rare earth science and technology. In the metallurgical industry
rare earth metals or fluorides, silicides added steel, can play a refining, desulphurization, in the role of harmful impurities and the low melting point, and can improve the processing properties of steel; rare earth ferrosilicon alloy, RE-Si-Mg alloy as the production of rare earth nodular cast iron, ductile iron in particular because of this there are special requirements for the production of ductile iron complex, is widely used in automobiles, tractors, diesel engines and other machinery manufacturing; rare earth metal added to the magnesium , aluminum, copper, zinc, nickel and other ferrous alloys, can improve the physical and chemical properties of the alloy and improve the alloy at room and high temperature mechanical properties.
In the petrochemical industry made with rare earth zeolite catalysts with high activity, selectivity, and strong resistance to the advantages of heavy metal poisoning, which replaced the aluminum catalyst used in petroleum cracking process; in Ammonia production process, with a small amount of nitric acid rare earth catalyst, the treatment gas than the nickel-alumina catalyst by 1.5 times; in the synthesis of butadiene rubber and isoprene rubber process, the use of rare earth naphthenate - triisobutylaluminum catalyst, excellent performance obtained with equipment hanging plastic less stable operation, the advantages of short post-treatment processes; composite rare earth oxide can also be used as a combustion engine exhaust gas purification catalyst, cerium naphthenate agent also can be used as paint driers.
In terms of glass-ceramic or rare earth oxides of rare earth concentrates processed can be used as polishing powder is widely used in optical glass, glasses, picture tubes, CRT, flat glass, plastic and metal tableware polishing; in the process of melting glass can be used to cerium oxide of iron has a strong effect, reducing the iron content of glass in order to achieve the purpose of removal of green glass; adding rare earth oxides can be produced for different purposes optical glass and special glass, including through infrared, UV-absorbing glass, acid and heat-resistant glass, anti-X-ray glass, etc.; in pottery glazes and enamels in the addition of RE, can reduce the fragmentation of the glaze, and to make products show different colors and gloss, are widely used in ceramic industry. In the new rare earth materials
cobalt and neodymium iron boron permanent magnet materials with high remanence, high coercivity and high energy product, is widely used in electronic and aerospace industries; pure rare earth oxides and ferric oxide compounds from the garnet-type ferrite single crystal and polycrystalline, can be used in microwave and electronics industry; the production of high purity neodymium oxide and neodymium yttrium aluminum garnet glass, can be used as solid-state laser materials; six-boron rare-earth compounds can be used to produce electron emission cathode; lanthanum nickel is up 70 new developments in hydrogen storage materials; Lanthanum Chromite is a high-temperature thermoelectric material; In recent years, yttrium barium copper around the world using oxygen to improve the barium oxide production of superconducting material that can be obtained at liquid nitrogen temperature superconductors, the superconducting materials research breakthrough has been made. In addition, rare earth is also widely used for lighting, projection TV phosphors, phosphor intensifying screens, three-color phosphor, light pink copy; in agriculture, field crops to the small amount of rare earth nitrate fertilizer can increase its output of 5 10%; in the textile industry, the rare earth chloride is widely used in tanning skins, fur dyeing, yarn dyeing and carpet dyeing and so on.
Address: Baisha Township
Yingde flotation mining sites used hydrochloric acid, sulfuric acid flowing into the agricultural valley, the water pollution of the environment, causing soil erosion, is the generations of people can not save The.
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