Molecular Formula | Nd |
Molar Mass | 144.24 |
Density | 7.003 g/mL at 25 °C (lit.) |
Melting Point | 1021 °C (lit.) |
Boling Point | 3074 °C (lit.) |
Water Solubility | Soluble in dilute acids. Decomposes in water. |
Appearance | ingot |
Specific Gravity | 7.003 |
Color | Silver |
Exposure Limit | ACGIH: TWA 2 ppm; STEL 4 ppmOSHA: TWA 2 ppm(5 mg/m3)NIOSH: IDLH 25 ppm; TWA 2 ppm(5 mg/m3); STEL 4 ppm(10 mg/m3) |
Merck | 13,6478 |
Sensitive | Air & Moisture Sensitive |
Use | For the manufacture of rare earth permanent magnetic materials |
Risk Codes | R11 - Highly Flammable R36/37/38 - Irritating to eyes, respiratory system and skin. R14/15 - R36/38 - Irritating to eyes and skin. R14 - Reacts violently with water |
Safety Description | S16 - Keep away from sources of ignition. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S33 - Take precautionary measures against static discharges. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S43 - In case of fire use ... (there follows the type of fire-fighting equipment to be used.) |
UN IDs | UN 3208 4.3/PG 1 |
WGK Germany | 3 |
RTECS | QO8575000 |
FLUKA BRAND F CODES | 10 |
TSCA | Yes |
HS Code | 28053011 |
Hazard Class | 8 |
Packing Group | III |
Raw Materials | Rare earth chlorides Neodymium(III)-oxide |
resistivity | 64.0 ***-CM, 20°C |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Introduction | neodymium is a soft silver metal element of the lanthanide series 60; ram 144.24; rd 7.004(20 °). It is present in forsterite and monazite and is recovered from it by an ion exchange process. There are seven natural isotopes, all of which are stable except for neodymium 144, which is weakly radioactive (half-life of 10 10 -10 15 years). The metal is used to color the glass purple-Violet, making it dichroic. It is also used in mixed metals (18% neodymium) and Nd-Fe-B alloys for magnets. It was discovered by Karl von Wilsbach (1856-1929) in 1885. There are seven kinds of neodymium isotopes in nature: neodymium 142, 143, 144, 145, 146, 148, 150, among which neodymium 142 is the highest. |
physical properties | neodymium is the third highest rare earth element in the Earth's crust (24 ppm). It reacts with moist air and loses its gloss in dry air, forming a coating of Nd3O3, an oxide with a light blue color that will peel off, leaving the bare metal, the oxidation was then continued. There are 47 isotopes of neodymium, seven of which are considered stable isotopes, which together make up the total abundance of the Earth's crust. Two of them are radioactive, but have a long half-life because they are still present on Earth and are therefore considered stable. |
Source | Although neodymium is the 28th most abundant element on Earth, its content ranks third among all rare earth elements. It is found in monazite, forsterite and allantoite ores. Its main ore is monazite sand, which is a mixture of Ce,La,Th,Nd,Y and small amounts of other rare earths. Some monazite sands have a weight content of more than 50%. |
Discovery History | in 1839, a mixture of lanthanum and neodymium was discovered by C.G.Mosander from Sweden. since then, chemists in various countries have paid special attention to the separation of new elements from the discovered rare earth elements. Praseodymium and neodymium were discovered in 1885 by A.V.Welsbach, from A mixture of praseodymium and neodymium, considered to be "new elements. One of them was named neodidyium, which was later reduced to neodyium, the element symbol Nd, which is the neodymium element. neodymium, praseodymium, gadolinium, and samarium were all isolated from didyium, a rare earth element considered at the time. Due to their findings, didyium is no longer retained. And it is their discovery opens the third door to the discovery of rare earth elements, is the third stage of the discovery of rare earth elements. But this is only half of the work of the third phase. The exact would be the opening of the cerium gate or the completion of the separation of cerium, and the other half would be the opening of the yttrium gate or the completion of the separation of yttrium. Natural neodymium is a mixture of seven isotopes, one of which has a long half-life. Twenty-seven other radioisotopes and isomers were also found. |
Applications | The main applications of neodymium include lasers, glass coloration and coloring, dielectrics, the most important thing is to serve as the basis for the ND-Fe-B (Nd2Fe14B) permanent magnet.|
preparation | neodymium is mainly extracted from the two most abundant rare earth minerals, monazite and basite. Monazite is a rare earth-thorium phosphate, usually containing 9 - 20% of neodymium. Bastnasite is a rare earth fluorocarbon ore containing 2 - 15% of neodymium. Both kinds of ore are first heated and cracked with concentrated sulfuric acid or sodium hydroxide. The process for recovering monazite ore using sulfuric acid is as follows: The ore is heated with sulfuric acid to convert neodymium to water-soluble sulfate. The product mixture is subjected to excess water treatment to separate neodymium as a soluble sulfate from water-insoluble sulfates and other residues of other metals. If Monazite is used as the starting material, the solution is treated with sodium pyrophosphate to separate thorium from neodymium and other soluble rare earth sulfates. This precipitated thorium pyrophosphate. Alternatively, the solution can be partially neutralized with caustic soda at a pH of 3 to 4 to selectively precipitate thorium as thorium hydroxide. The solution was then treated with ammonium oxalate to precipitate the insoluble rare earth metal oxalate. The resulting rare earth oxalate is calcined in air to decompose into oxides. In this rare earth oxide mixture, the composition of the individual oxides may vary depending on the source of the ore and may contain up to 18% neodymium oxide. In addition, the above oxalate is digested with sodium hydroxide to convert the rare earth metal into a hydroxide. Cerium forms a tetravalent hydroxide, Cerium hydroxide Ce(OH)4, which is insoluble in dilute nitric acid. When dilute nitric acid is added to this rare earth hydroxide, the cerium (IV) hydroxide forms an insoluble alkaline nitrate, which is filtered from the solution. Cerium can also be removed by several other methods. One such method is the calcination of the rare earth hydroxide at 500°C in air. Cerium is converted to cerium oxide, CeO2, while other lanthanides are oxidized to trivalent oxides. These oxides are dissolved in moderate concentrations of nitric acid. The cerium nitrate thus formed and all remaining thorium nitrate is now removed from the nitrate solution by reflux contact with tributyl phosphate, and after removal of cerium (and thorium), the nitric acid solution of the rare earth is treated with ammonium nitrate. Lanthanum forms the most water-insoluble double salt with ammonium nitrate, which can be removed from the solution by repeated crystallization. Neodymium was obtained from a solution of magnesium dinitrate by continuous fractionation. |
Health effects | Many compounds (salts) of neodymium are irritating to the skin and toxic if inhaled or ingested. Some are explosive (eg, neodymium nitrate [Nd(NO3)3]). |
Application | for the manufacture of rare earth permanent magnetic materials |
category | flammable liquid |
toxicity grade | high toxicity |
Acute toxicity | brain-human 0.017 mg/kg |
flammability hazard characteristics | oxidation in air; Flammable hydrogen in water; solvent combustion producing irritating smoke |
storage and transportation characteristics | The warehouse is ventilated and dried at low temperature; It is stored separately from the oxidant |
extinguishing agent | dry powder, dry sand, carbon dioxide, foam, 1211 extinguishing agent |