Cov hlau tsis tshua muaj hauv ntiaj teb tau siv dav hauv kev lag luam, thiab ntau dua purity tsawg lub ntiaj teb hlau feem ntau yog siv los ntsuas lub cev thiab tshuaj. Muaj plaub lub ntsiab purification txoj kev siv nyob rau hauv lub laboratory, uas yog lub tshuab nqus tsev melting, nqus distillation los yog sublimation, electromigration, thiab cheeb tsam melting.
Vacuum melting method
Melt thiab purify lub ntiaj teb tsis tshua muaj hlau nrog qis vapor siab, xws li scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, gadolinium, terbium, thiab lutetium, ntawm lub tshuab nqus tsev siab tshaj 10-6 torr, ntawm qhov kub ntawm 200 mus rau 1000 degree siab tshaj qhov melting point ntawm cov hlau. Nyob rau hauv cov ntaub ntawv no, impurities nrog siab vapor siab xws li alkali hlau, alkaline ntiaj teb hlau, fluorides, thiab tsawg valence oxides (RO) yuav distilled tawm, tab sis cov nyhuv tshem tawm ntawm impurities nrog kub boiling ntsiab lus xws li tantalum, hlau, vanadium, thiab chromium tsis zoo.
Vacuum distillation method
Kuj tseem hu ua lub tshuab nqus tsev sublimation. Distill thiab purify yttrium, gadolinium, terbium, thiab lutetium ntawm lub tshuab nqus tsev kawm ntawv ntawm 10-6-10-9 torr thiab kub ntawm 1600-1725 degree, thiab sublimate thiab purify scandium, dysprosium, holmium, erbium, thulium, samarium, europium , thiab ytterbium ntawm 1550-1650 degree . Nyob rau hauv cov xwm txheej no, tsis tshua muaj vapor siab hlau impurities xws li tantalum thiab tungsten, nrog rau cov tebchaw uas muaj carbon, nitrogen, thiab oxygen, yuav nyob twj ywm hauv lub crucible. Txoj kev no feem ntau yog siv ua ke nrog lub tshuab nqus tsev melting.
Txoj kev electromigration
Siv ncaj qha tam sim no rau lub ntiaj teb tsis tshua muaj hlau pas nrig hauv lub tshuab nqus tsev ultra-siab lossis inert cua, thiab tuav nws rau 1-3 lub lis piam ntawm qhov kub thiab txias 100-200 degree qis dua qhov melting point ntawm cov hlau. Nyob rau hauv qhov kev txiav txim ntawm qhov kub thiab txias tam sim no hluav taws xob tam sim no, ntau yam impurity cov ntsiab lus sib sau ua ke ntawm cov pas ntsuas ntawm ob qho kawg vim qhov sib txawv ntawm cov nqi zoo, diffusion coefficient, thiab kev tsiv teb tsaws. Txiav tawm ob qhov kawg ntawm qhov ntsuas pas nrig, thiab qhov nruab nrab tuaj yeem ua kom huv ntxiv electromigration. Kev ua kom huv ntawm lanthanum, cerium, praseodymium, neodymium, gadolinium, terbium, yttrium, thiab lutetium siv txoj kev electromigration hauv chav kuaj muaj txiaj ntsig zoo rau kev tshem tawm cov impurities xws li carbon, oxygen, thiab nitrogen.
Regional melting txoj kev
Tsis tshua muaj lub ntiaj teb hlau rods undergo ntau cheeb tsam melting ntawm ib tug qeeb qeeb ceev (xws li 0.4 mm/min rau purifying yttrium) nyob rau hauv lub regional melting rauv, uas muaj ib tug tseem ceeb rau kev tshem tawm cov hlau impurities xws li hlau, txhuas. , magnesium, tooj liab, npib tsib xee, thiab lwm yam, tab sis tsis zoo rau oxygen, nitrogen, carbon, thiab hydrogen. Tsis tas li ntawd, electrolytic refining thiab cheeb tsam melting electromigration ua ke txoj kev muaj qee yam cuam tshuam rau purifying tsis tshua muaj ntiaj teb.