What are rare earths? \u2018Rare\u2019 means rare; \u2018earth\u2019 is usually used to refer to solid oxides that are insoluble in water, such as aluminum oxide, called clay, and magnesium oxide, called pyrophyllite; rare earth refers to certain metal oxides. To be precise, rare earth is a general term for 17 metal elements in the periodic table, including \u2018scandium\u2019, \u2018yttrium\u2019 and \u2018lanthanide elements\u2019. The oxides of these 17 rare earth elements are always mixed together.<\/p>\n\n\n\n
Rare earth elements: scandium, yttrium and lanthanide series a total of 17 elements<\/p>\n\n\n\n Rare earth elements are located in the third column of the periodic table, namely scandium (SC), yttrium (Y), and lanthanum (La).<\/p>\n\n\n\n However, Lanthanum stands for \u2018Lanthanide\u2019, which is a group of 15 elements: Lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm),<\/p>\n\n\n\n Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy),<\/p>\n\n\n\n Holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu).<\/p>\n\n\n\n Therefore, there are 17 rare earth elements in total, of which those with active properties and light atomic mass are called \u2018light rare earth elements\u2019, a total of 8:<\/p>\n\n\n\n Lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd),<\/p>\n\n\n\n promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd).<\/p>\n\n\n\n There are seven elements with heavier atomic masses, known as \u2018heavy rare earth elements\u2019:<\/p>\n\n\n\n Terbium (Tb), Dysprosium (Dy),Holmium (Ho), erbium (Er),<\/p>\n\n\n\n thulium (Tm), ytterbium (Yb), lutetium (Lu).<\/p>\n\n\n\n Rare earth elements have many special properties, a few of which are introduced below.<\/p>\n\n\n\n 1. Generally speaking, rare earth elements are more active than \u2018aluminum\u2019.<\/p>\n\n\n\n They react with oxygen to form oxides, react with hydrogen to form hydrides, form compounds with many non-metallic elements and react with many acids and bases to form \u2018rare earth salts\u2019;<\/p>\n\n\n\n 2.As the \u2018atomic number\u2019 decreases, the\u2018activity\u2019 increases; as the \u2018atomic number\u2019 increases, the \u2018metallicity\u2019 decreases.<\/p>\n\n\n\n 3. Alloys of \u2018lanthanide elements\u2019 and \u2018transition metals\u2019 are important hydrogen storage materials, such as LaNi5.<\/p>\n\n\n\n It has a strong hydrogen storage capacity under several atmospheres of pressure and can release hydrogen by reducing the pressure.<\/p>\n\n\n\n 4. Rare earth metals and their oxides, hydroxides, and carbonates are originally insoluble in water. Still, they can react with hydrochloric acid to produce \u2018rare earth chlorides\u2019, which are easily soluble in water, and the higher the temperature, the greater the solubility.<\/p>\n\n\n\n 5.Rare earth metals, their oxides and hydroxides react with sulfuric acid to form \u2018rare earth sulfates\u2019, and their solubility in water also has a strong regularity.<\/p>\n\n\n\n 6.\u2018Rare earth sulfates\u2019 can form \u2018complex salts\u2019 with \u2018alkaline earth metal sulfates\u2019. The solubility of these complex salts varies greatly and they are easy to separate.<\/p>\n\n\n\n The above solubility characteristics will be used in the separation and extraction technology of rare earth elements.<\/p>\n\n\n\n 7.Rare earth elements are relatively active, which can easily fuse with other crystals, making the crystal structure small and dense.<\/p>\n\n\n\n 8.The atomic structure of rare earth elements is quite special and has multiple \u2018energy levels\u2019. How do we know this phenomenon? When rare earth elements are illuminated with a certain light to observe their spectra, it can be found that there is more than one spectrum, which shows that the atoms of rare earth elements have multiple “energy levels”.<\/p>\n\n\n\n 9. There are about 30,000 absorption spectra of all rare earth element atoms or ions, all of which are \u2018narrow-band spectra\u2019 from infrared to ultraviolet. Since the frequency of the absorption spectrum is also the frequency of the excitation-emission spectrum, rare earth elements can emit special light when irradiated with excitation light. For this reason, rare earths have become a huge treasure trove of luminescent materials, from which many new luminescent materials can be discovered. Moreover, rare earth elements have low luminescence conditions, strong luminescence ability, high luminescence efficiency, and pure light color.<\/p>\n\n\n\n Rare earth elements are known as \u2018industrial gold\u2019 and \u2018industrial vitamins\u2019, which means that they are important and practical and are everywhere in the industry. When they are used in a material, they will magically improve the performance and production efficiency, increase scientific and technological content, and promote technological progress of that material. More specifically, modern high-tech products cannot do without the participation of rare earths. The following is a summary of the application of rare earths in several fields.<\/p>\n\n\n\n \u2018Rare earth ferrosilicon alloy\u2019 and \u2018rare earth silicon-magnesium alloy\u2019 are used as spheroidizing agents in cast iron, which can transform the strip-shaped \u2018iron-carbon crystals\u2019 into \u2018spheres\u2019, thus becoming \u2018ductile iron\u2019, which greatly improves the processing performance and mechanical properties of cast iron. It plays a huge role in the machinery manufacturing industry.<\/p>\n\n\n\n Adding 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 at room and high temperatures.<\/p>\n\n\n\n The well-known \u2018king of permanent magnets\u2019 is the \u2018NdFeB\u2019 alloy, in which rubidium is a rare earth element. Strong permanent magnets have a wide range of uses, like in \u2018permanent magnet motors\u2019, \u2018magnetic resonance imaging\u2019, and \u2018electrical components\u2019.<\/p>\n\n\n\n In the petrochemical industry, molecular \u2018cracking\u2019 and \u2018polymerization\u2019 are very common, but they all require the use of catalysts. Adding rare earth elements to the catalyst can double the efficiency; making the catalyst into a “molecular sieve catalyst” with “good permeability” and “large contact area” can double the catalytic effect.<\/p>\n\n\n\n In chemical printing and dyeing, the use of rare earths can make dyeing stable and bright.<\/p>\n\n\n\n \u2018Special optical glass\u2019 can be made by adding rare earth elements, some of which can pass infrared rays, absorb ultraviolet rays, resist heat, acid, and alkali, or block X-rays. These \u2018high-grade optical glasses\u2019 are widely used in civilian high-tech.<\/p>\n\n\n\n High-power \u2018laser crystals\u2019 must contain rare earth elements. This type of laser can be used in the mechanical processing, scalpels, etc.<\/p>\n\n\n\n Adding rare earths to ceramic glazes and porcelain glazes can not only make the sintered products present different colors and luster but also reduce the breakage of the glaze. Fine-grained rare earth oxides can be widely used as polishing agents for various types of glass.<\/p>\n\n\n\n By adding rare earths to optical fiber materials, signals can travel through the fiber with less loss and can travel farther.<\/p>\n\n\n\n By doping rare earths into optical fibers and irradiating them with LED lights, the doped rare earth elements can be stimulated to emit light. This principle can be used to make a \u2018relay amplifier\u2019 for optical fiber signal transmission, which we call “pump light”. \u2018Pump light\u2019 can also be used to make high-power lasers.<\/p>\n\n\n\n High-tech thin-film displays generally use “phosphors that display different colors”, and these phosphors require the participation of different rare earth elements.<\/p>\n\n\n\n Heavy rare earth elements can generally absorb neutrons and turn into corresponding isotopes, so they can participate in \u2018uranium raw materials\u2019 and control the fission rate. Those isotopes are also radioactive and have lower energy, so they can be used in \u2018local chemotherapy\u2019 and \u2018radioactive display tracking\u2019 in the medical field.<\/p>\n\n\n\n Research results show that adding a small amount of rare earth to the soil can promote seed germination, increase the seed germination rate, and promote seedling growth; it can increase plant chlorophyll content, enhance photosynthesis, promote root development, and increase root nutrient absorption; it can improve the disease resistance, cold resistance, and drought resistance of crops; spraying fruits with an appropriate amount of rare earth mixture can improve the quality of the fruits. The reason is that the light emitted by rare earth elements under sunlight is beneficial to plant growth.<\/p>\n\n\n\n Rare earth application area consumption ratio<\/strong><\/p>\n\n\n\n Rare earths are indispensable materials for new technol […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-160","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/posts\/160","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/comments?post=160"}],"version-history":[{"count":1,"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/posts\/160\/revisions"}],"predecessor-version":[{"id":161,"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/posts\/160\/revisions\/161"}],"wp:attachment":[{"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/media?parent=160"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/categories?post=160"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.hnrem.com\/index.php\/wp-json\/wp\/v2\/tags?post=160"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"\u56fe\u72471\"\/](\"https:\/\/www.hnrem.com\/upload\/news\/1730278262218372.jpg\")
<\/figure>\n\n\n\nIntroducing some \u2018rare earth properties\u2019<\/strong><\/h2>\n\n\n\n
![\"\u56fe\u72473\"\/](\"https:\/\/www.hnrem.com\/upload\/news\/1730278362808451.png\")
<\/figure>\n\n\n\nWhat are the uses of rare earths?<\/strong><\/h2>\n\n\n\n
1.Usage in metallurgical industry<\/h3>\n\n\n\n
2.Application in strong magnetic materials<\/h3>\n\n\n\n
3.Usage in petrochemical industry<\/h3>\n\n\n\n
4.Usage in glass ceramics<\/h3>\n\n\n\n
5.Usage for optical fiber communication<\/h3>\n\n\n\n
6.Usage for electrochromic display<\/h3>\n\n\n\n
7.Used for radioactivity<\/h3>\n\n\n\n
8.Usage in agriculture<\/h3>\n\n\n\n
![\"\u56fe\u72472\"\/](\"https:\/\/www.hnrem.com\/upload\/news\/1730278472736418.jpg\")
<\/figure>\n","protected":false},"excerpt":{"rendered":"