프로메튬
프로메튬 · 61Pm · Prometio · Chebi:33373 · promethium-147 · promethium atom · promethium ISO 9001：2015 REACH
식별자 및 물리적 특성
| CAS No. | 22541-16-8 |
|---|---|
| 분자식 | Pm |
| 평균 분자량 | 144.9128 g/mol |
| 단동위원소 질량 | 144.91276 g/mol |
| SMILES | [Pm] |
| InChIKey | VQMWBBYLQSCNPO-UHFFFAOYSA-N |
| PubChem CID | 23944 |
| ChEBI | CHEBI:33373 |
| EC No. | 231-121-9 |
| DTXSID | DTXSID4047755 |
| 현지명 | 프로메튬 |
화학 및 물리적 성질
| 극성 표면적 | 0 |
|---|---|
| 수소 결합 공여자 수 | 0 |
| 수소 결합 수용자 수 | 0 |
| 회전 가능 결합 수 | 0 |
| 무거운 원자 수 | 1 |
| 형식 전하 | 0 |
| 복잡도 | 0 |
| 물질 분류 | Physical/Radiation -> Radionuclides |
| SpringerMaterials Properties | electron density of states |
| Physical Description | Solid metal[Merck Index] |
| 녹는점 | 1080° (Weigel) |
| 끓는 점 | 3000°C |
| 밀도 | 7.22 |
| 물리적 상태 | 은빛 금속 |
| 색상 | silvery metalhexagonal, hexane |
| 비열 | Cp(gas): 0.17 J/(g·K), at 25℃ |
| EPA | Promethium (7440-12-2) |
화학적 성질
silvery metal; enthalpy of sublimation is 348kJ/mol (estimated); radius of atom is 0.1811nm; radius of ion is 0.0979 nm; Pr+++has yellow-colored solutions [KIR82]
안전 및 규제
| GHS 분류 | Not Classified |
|---|---|
| 유해성 요약 | All isotopes are radioactive (mass numbers = 132-155)Pm-145 has the longest half-life at 17.7 years, an alpha emitterPresent at low levels in uranium ores[Merck Index] The stable rare earth compounds cause benign and other pneumoconioses, but Promethium is not stable. [Reference #2] Pm-147 with a half-life of 2.6 years is the most useful isotope. Pm-145 has the longest half-lifeit has a specific activity of 940 Ci/g. See Radiation, Ionizing. |
| Hazard Classes and Categories | Not Classified |
| EPA Provisional Peer-Reviewed Toxicity Values | PromethiumPDF DocumentInadequate information to assess carcinogenic potential2007 |
| 운송 번호(UN) | 2912 |
| 위험 등급 | 7 |
용도
역사
The discovery of this element is credited to J.A. Marinsky and L.E. Glendenin who, in 1945, identified its long-lived isotope Pm-147 (t1/2 2.64 years) in the fission products of uranium. They named the element after Prometheus, who according to Greek mythology stole fire from heaven. The element was first isolated from fission product wastes by G.W. Parker and P.M. Lantz in 1948. It first was recovered from natural sources by O. Erametsa in 1965. An amount less than 0.5 g was recovered from 20 tons of rare earths.Promethium does not occur in metallic form in nature. Minute quantities are associated with other rare earths. It also is detected in uranium fission products. It is probably the rarest of the lanthanide elements.Promethium has very limited applications. It is used in phosphor lights to produce signals. Also, it is used as a beta particle source for thickness gages, nuclear batteries, and portable x-ray units.
용도
Promethium-147 is used in the manufacture of luminescent paint for watch dials, as well as being a source of beta rays.
제조 및 합성 방법
생산 방법
Promethium-147, the isotope used commercially, is isolated from fission product wastes. The radioactive materials must be handled safely in a glove box. The metal complexes either with ethlenediaminetetraacetic acid (EDTA) or diethylenetriaminepentaacetic acid (DTPA) and is isolated by elution from Dowex 50.The metal may be obtained from its fluoride salt, promethium(III) fluoride by heating with lithium metal in a double tantalum crucible at 700 to 800°C in vacuum and then increasing the temperature to 1,100°C.