Magical Rare Earth Element: Cerium

Cerium yog lub undisputed 'tus tij laug loj' nyob rau hauv lub loj tsev neeg ntawm tsawg ntiaj teb ntsiab. Ua ntej, tag nrho cov nplua nuj ntawm cov av tsis tshua muaj nyob rau hauv lub crust yog 238ppm, nrog cerium ntawm 68ppm, accounting rau 28% ntawm tag nrho cov tsawg lub ntiaj teb muaj pes tsawg leeg thiab qeb duas; Qhov thib ob, cerium yog qhov thib ob lub ntiaj teb tsis tshua pom muaj cuaj xyoo tom qab kev tshawb pom ntawm yttrium (1794). Nws daim ntawv thov yog dav heev, thiab "cerium" yog unstoppable

Qhov Discovery ntawm Cerium Element
640
Carl Auer von Welsbach: koj puas xav tau ntau tus thwjtim?

Cerium tau tshawb pom thiab muaj npe nyob rau xyoo 1803 los ntawm German Kloppers, Swedish chemist J öns Jakob Berzelius, thiab Swedish mineralogist Wilhelm Hisinger. Nws yog hu ua ceria, thiab nws cov ore yog hu ua cerite, nyob rau hauv lub cim xeeb ntawm Ceres, ib tug asteroid nrhiav tau nyob rau hauv 1801. Qhov tseeb, hom cerium silicate yog ib tug hydrated ntsev uas muaj 66% mus rau 70% cerium, hos tus so yog cov ntsiab lus ntawm calcium. , hlau, thiabyttrium.

Thawj qhov kev siv cerium yog lub qhov cub roj tsim los ntawm Austrian chemist Carl Auer von Welsbach. Xyoo 1885, nws tau sim sib xyaw ntawm magnesium, lanthanum, thiab yttrium oxide, tab sis cov khoom sib xyaw no tawm lub teeb ntsuab tsis muaj kev vam meej.

Xyoo 1891, nws pom tias cov ntshiab thorium oxide tsim lub teeb zoo dua, txawm tias nws yog xiav, thiab sib xyaw nrog Cerium (IV) oxide los tsim lub teeb dawb. Tsis tas li ntawd, Cerium (IV) oxide kuj tuaj yeem siv los ua cov khoom siv rau thorium oxide combustion.

Cerium hlau
cerium hlau
★ Cerium yog cov hlau nplaum thiab mos nyiaj dawb nrog cov khoom siv. Thaum raug huab cua, nws yuav raug oxidized, tsim cov xeb zoo li tev oxide txheej. Thaum rhuab, nws hlawv thiab reacts sai nrog dej. Ib tug centimeter loj cerium hlau qauv kiag li corrode nyob rau hauv ib xyoos. Tsis txhob sib cuag nrog huab cua, muaj zog oxidants, muaj zog acids, thiab halogens.

★ Cerium feem ntau muaj nyob rau hauv monazite thiab bastnaesite, nrog rau cov khoom fission ntawm uranium, thorium, thiab plutonium. Kev puas tsuaj rau ib puag ncig, yuav tsum tau saib xyuas tshwj xeeb rau cov pa phem ntawm lub cev dej.

★ Cerium yog 26th feem ntau cov khoom, suav txog 68ppm ntawm lub ntiaj teb lub pob zeb, thib ob tsuas yog tooj liab (68ppm). Cerium muaj ntau dua li cov hlau zoo tib yam xws li txhuas (13 teev) thiab tin (2.1ppm).

 

Cerium Electron configuration
640
Electronic kev npaj:
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p66s2 4f1 5d1
★ Cerium nyob tom qab lanthanum thiab muaj 4f electrons pib los ntawm cerium, ua rau nws yooj yim rau kev koom nrog cov tshuaj tiv thaiv. Txawm li cas los xij, 5d orbital ntawm cerium yog nyob, thiab cov nyhuv no tsis muaj zog txaus hauv cerium.

★ Feem ntau Lanthanide tsuas tuaj yeem siv peb lub tshuab hluav taws xob li Valence electron, tshwj tsis yog cerium, uas muaj cov qauv hluav taws xob sib txawv. Lub zog ntawm 4f electrons yuav luag zoo ib yam li ntawm sab nraud 5d thiab 6s electrons delocalized nyob rau hauv lub xeev hlau, thiab tsuas yog ib tug me me lub zog yuav tsum tau hloov cov txheeb ze txoj hauj lwm ntawm cov hluav taws xob hluav taws xob theem, uas ua rau ob valence ntawm. +3 thiab + 4. Lub xeev ib txwm yog + 3 valence, qhia + 4 valence hauv dej anaerobic.
Kev siv cerium
IMG_4654
★ tuaj yeem siv los ua cov khoom siv hlau nplaum thiab rau kev tsim cov ntsev ntsev, thiab lwm yam.

★ Nws tuaj yeem siv los ua iav ntxiv kom nqus tau ultraviolet thiab infrared rays, thiab yog siv dav hauv Tsheb iav.

★ tuaj yeem siv los ua cov khoom siv tiv thaiv ib puag ncig zoo, thiab tam sim no tus neeg sawv cev feem ntau yog lub tshuab hluav taws xob ua kom huv si, uas tiv thaiv tau ntau cov pa hluav taws xob hauv tsheb los ntawm kev tawm mus rau saum huab cua.

★ Lub teebtsawg ntiaj teb yamFeem ntau yog tsim los ntawm cerium raws li cov nroj tsuag kev loj hlob regulators tuaj yeem txhim kho cov qoob loo zoo, nce yield, thiab txhim kho qoob loo kev ntxhov siab.

★ Cerium sulfide tuaj yeem hloov cov hlau xws li txhuas thiab cadmium uas tsim kev puas tsuaj rau ib puag ncig thiab tib neeg cov pigments, tuaj yeem ua xim yas, thiab tuaj yeem siv rau hauv cov coatings thiab number case industries.

Cerium (IV) oxidetuaj yeem siv ua polishing compound, piv txwv li, hauv Chemical-mechanical polishing (CMP).

★ Cerium kuj tseem siv tau los ua cov khoom siv hydrogen, cov khoom siv thermoelectric, cerium tungsten electrodes, Ceramic capacitor, piezoelectric ceramics, cerium silicon carbide abrasives, roj cell raw cov ntaub ntawv, roj av catalysts, cov khoom siv hlau nplaum ruaj khov, cov ntaub ntawv kho mob, ntau yam hlau alloy thiab tsis yog- ferrous hlau.


Post lub sij hawm: Jul-03-2023