Europium
Europium atomic absorption standard solution
CAS: 7440-53-1
Molecular Formula: Eu
Europium - Names and Identifiers
Europium - Physico-chemical Properties
| Molecular Formula | Eu |
| Molar Mass | 151.96 |
| Density | 5.24 g/mL at 25 °C (lit.) |
| Melting Point | 822 °C (lit.) |
| Boling Point | 1527 °C (lit.) |
| Water Solubility | Reacts with water. |
| Appearance | ingot |
| Specific Gravity | 5.24 |
| Color | Silver/gray |
| 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 | 13,3937 |
| Sensitive | Air & Moisture Sensitive |
Europium - Risk and Safety
| Risk Codes | R14/15 - R17 - Spontaneously flammable in air R34 - Causes burns |
| Safety Description | S43 - In case of fire use ... (there follows the type of fire-fighting equipment to be used.) S7/8 - S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S27 - Take off immediately all contaminated clothing. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S23 - Do not breathe vapour. |
| UN IDs | UN 2813 4.3/PG 2 |
| WGK Germany | 3 |
| FLUKA BRAND F CODES | 1-10 |
| TSCA | Yes |
| HS Code | 28053090 |
| Hazard Class | 4.1 |
| Packing Group | II |
Europium - Reference Information
| resistivity (resistivity) | 81 μΩ-cm, 20°C |
| EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
| introduction | europium is one of the rarest rare earth elements. Its content on the earth is only 1.1ppm. It is a soft, shiny, steel-gray metal with strong ductility and malleability, which means it can be processed into a variety of shapes. It looks and feels like a lead element, but it's slightly heavier. It is the most chemically active of all rare earth elements. There are 45 isotopes of europium. Two of them are considered stable and account for 100% of europium found on earth: Eu- 151(47.81%) and Eu-153(52.19%). The other 53 isotopes are radioactive and are mainly synthesized artificially by electron capture. |
| Physical properties | Like other rare earth metals except lanthanum, europium burns in air at 150 to 180°C. Europium is as hard as lead and has strong toughness. It is the most active rare earth metal and oxidizes rapidly in the air. Its reaction with water is similar to calcium. Metamorphic rocks and solitary rocks are the main ores containing europium. Europium has been identified in the spectra of the sun and some stars. |
| Source | Europium is the 13th most abundant of all rare earth elements and the 55th most abundant element on earth. There are more europium in on the earth than all gold and silver deposits. Like many other rare earths, europium also exists in the river sand in India and Brazil and the beach sand in Florida, and exists in monazite, fluocerite, silicite and brownstone ore in the deposit. Facts have proved that it is very difficult to separate europium from other rare earth elements. Nowadays, the ion exchange method is used to extract europium from other rare earths found in monazite sand (ore). |
| Use | The excitation of europium atoms by absorbing ultraviolet rays can cause energy level transitions in the atoms and produce visible radiation. It is certain types of lasers and other optoelectronic devices The dopant of glass. Europium oxide (Eu2O3) is widely used as a red phosphor for televisions and fluorescent lamps, as well as an activator for ytthree-based phosphors. In energy-saving fluorescent lighting, europium not only provides the necessary red, but also blue. Some commercial blue phosphors are based on europium and are used in color TV sets, computer screens and fluorescent lamps. Its luminescence is also valuable in medicine, surgery and biochemistry. Europium is used to capture thermal neutrons and is used as a nuclear control rod for atomic power stations. The natural mixture of europium isotopes absorbed by thermal neutrons is a 4600 barn. Europium salts are used in the coating of color TV cathode ray tubes, and organic derivatives are used in nuclear magnetic resonance spectroscopy. |
| Preparation | Europium generally appears with other rare earth elements, so it is mined together and separated later. Ores such as fluorocarbon, cerium-niobium perovskite, yttrium and monazite contain exploitable rare earth elements. The first two are orthophosphate minerals LnPO4(Ln represents all lanthanides except promethium), and yttrium is a fluorocarbon mineral LnCO3F. Monazite contains both thorium and yttrium, and thorium and its decay products are radioactive, making the processing process more difficult. There are several methods for extracting and separating various lanthanides from raw ores. The choice of method should consider the composition and concentration of minerals, as well as the distribution of each lanthanide element in the mineral concentrate. The ore is first baked, and then immersed back and forth by acid and alkali to form a mixed concentrate of lanthanide elements. If cerium is the majority, cerium (III) can be converted into cerium (IV) and precipitated. Solvent extraction or ion exchange chromatography can increase the proportion of europium in the mixture. Europium (III) can be converted into europium (II) by zinc, zinc amalgam, ionization and other methods. The latter has similar chemical properties to alkaline earth metals, so it can be precipitated in the form of carbonate or co-precipitated with barium sulfate. [25] To prepare europium metal, a mixture of molten europium trichloride (EuCl3) and sodium chloride (NaCl) or calcium chloride (CaCl2) can be ionized, with a graphite electrolytic cell as the cathode and graphite as the anode. The reaction also produces chlorine. |
Last Update：2024-04-09 02:00:04
