• Title/Summary/Keyword: 희토류금속

Search Result 123, Processing Time 0.033 seconds

Crystal Growth and Optical Property of Rutiles Doped with Impurity Ions (불순이온을 첨가한 Rutile의 단결정 성장에 관한 연구)

  • 이성영;김병호;정석종;유영문
    • Korean Journal of Crystallography
    • /
    • v.10 no.1
    • /
    • pp.83-87
    • /
    • 1999

  • 부유대용융법에 의하여 전이금속, 희토류금속, 및 3A족 금속이온의 종류와 농도를 조절하면서 Rutile 단결정을 성장하였으며, 결정결함과 1.55 ㎛에서의 광 투과도에 미치는 각 불순이온의 영향을 조사하였다. 주입된 불순이온 중에서 양호한 결정형을 나타내는 이온은 V5+, Fe3+, Al3+, Zr4+, Ga3+, Sc3+이었으며, Al3+, Zr4+, Sc3+ 이온은 우수한 투과도를 나타내었다. 성장된 결정 중에서 가장 양호한 결정형을 제공하고, 산소결핍 및 low-angle grain boundaries의 형성을 최대로 억제하며, 양호한 투과도를 나타낸 우수한 품질의 Rutile 단결정은 TiO2 99.4 at%-Al2O3 0.6 at%로 평가되었다.

  • PDF

Studies on the New Analytical Methods for Separation and Recovery of Rare Earth Metals (I) : Adsorption Characteristics of U(VI) Ion by New Synthetic Resins with Macrocyclic Compounds (희토류금속 분리 및 회수를 위한 분석화학적 연구 (제1보) : 우라늄(VI)의 분리회수를 위한 선택이온교환수지 합성과 우라늄(VI) 금속이온의 흡착특성)

  • Jung Oh Jin;Hak Jin Jung;Joon Tea Kim
    • Journal of the Korean Chemical Society
    • /
    • v.32 no.4
    • /
    • pp.358-370
    • /
    • 1988

  • Several new ion exchange resins have been synthesized from chloromethyl styrene-1,4-divinylbenzene(DVB) with 1%, 2%, 4%, and 10%-crosslinking and macrocyclic ligands of cryptand type by interpolymerization method. The adsorption characteristics and the pH, time, solvents and concentration dependence of the adsorption of metal ions by this resin were studied. The correlation between the separation characteristics of uranium, rare earths and transition metal on the resins and the stability constants of complexes with macrocyclic ligands have been examined. The resins were very stable in both acidic and basic media and have good resistance to heat at $280^{\circ}C$. The $UO_2^{+2}$ aqueous solution are not adsorbed on the resins below pH 3.0, but the power of adsorption of $UO_2^{2+}$ increased rapidly above pH 4.0. The optimum equilibrium time for adsorption of metallic ions was twenty minutes and adsorptive power decreased in proportion to crosslinking size of the resins and order of dielectric constants of solvents used and the selective sequence for metal cations is in the order of $UO_2^{2+},\;Cu^{2+}\;and\;Nd^{3+}$.

  • PDF

Rare Metal Contents and Their Implications of Seabed Mineral Resources Explored by Korea (한국이 탐사 중인 해저광물자원의 희유금속 함량과 의미)

  • Pak, Sang-Joon;Moon, Jai-Woon;Lee, Kyeong-Yong;Chi, Sang-Bum
    • Economic and Environmental Geology
    • /
    • v.43 no.5
    • /
    • pp.455-466
    • /
    • 2010

  • Seabed mineral resources explored by Korea are categorized into major three types of deposit; manganese nodule, manganese crust and polymetallic sulfides. Pt displays high enrichment factors (400, ore/crust ratios) in manganese nodule. Rare earth oxide content in manganese nodule ranges from 0.037 to 0.302 REO % with mean value of 0.12 REO %. Both of Te and Pt are enriched elements in manganese crust, displaying enrichment factors of 10800 and 150, respectively. Rare earth oxide's contents of manganese crust are slightly higher than manganese nodule's (0.013~0.387 REO %, average = 0.18 REO %). Se and In are outstanding rare metals from seabed polymetallic sulfides, showing enrichment factors of 1300 and 110, respectively. Au (0.8~26.3 g/t) and Ag (0.9~348.0 g/t) are another enriched elements in polymetallic sulfides. The main concern at exploiting seabed mineral resource will be a securing rare metals for high-technology industries and rare metals from subsea mineral deposits will add economic values to commodity candidates such like Co, Ni and Cu.

  • PDF KSCI

Reductive reaction of U and Lanthanides using Cd-Li metal in LiCl-KCl Molten Salt (LiCl-KCl 용융염에서 Cd-Li 금속을 이용한 U 및 란탄족의 환원반응)

  • 우문식;이병직;김응호;유재형
    • Proceedings of the Korean Radioactive Waste Society Conference
    • /
    • 2004.06a
    • /
    • pp.339-339
    • /
    • 2004

  • 원자로를 이용하여 장수명핵종(long lived nucleus)을 소멸처리하는 과정에서 초우라늄(TRU, transuranium)과 희토류(RE, rare earth) 금속에 포함되어 있는 소량의 핵분열성(fissile) 물질인 우라늄을 제거할 필요가 있다. 본 실험은 LiCl-KCl 용융염계에서 전해제련법(Electrowinning)을 이용하여 용융염욕에 존재하는 우라늄을 제거하기 위하여 필요한 Cd-Li 양전극 물질을 제조하였고, 제조된 금속을 이용하여 우라늄 및 란탄족(Dy, Ce, Y, Nd, Gd) 금속의 환원 특성을 파악하였다.(중략)

  • PDF

Pyro-Electrochemical Reduction of a Mixture of Rare Earth Oxides and NiO in LiCl molten Salt (LiCl 용융염에서 NiO를 혼합한 희토류 산화물의 파이로 전해환원 특성)

  • Lee, Min-Woo;Jeong, Sang Mun
    • Korean Chemical Engineering Research
    • /
    • v.55 no.3
    • /
    • pp.379-384
    • /
    • 2017

  • An electrochemical reduction of a mixture of NiO and rare earth oxides has been conducted to increase the reduction degree of rare earth oxides. Cyclic voltammetry (CV) measurement was carried out to determine the electrochemical reduction behavior of the mixed oxide in molten LiCl medium. Constant voltage electrolysis was performed with various supplied charges to understand the mechanism of electrochemical reduction of the mixed oxide as a working electrode. After completion of the electrochemical reduction, crystal structure of the reaction intermediates was characterized by using an X-ray diffraction method. The results clearly demonstrate that the rare earth oxide was converted to RE-Ni intermetallics via co-reduction with NiO.

  • https://doi.org/10.9713/kcer.2017.55.3.379 인용 PDF KSCI

Optical Properties and Persistent Spectral Hole Burning of $Sm^{2+}$-doped into $Mg_{0.5}Sr_{0.5}FCl_{0.5}Br_{0.5}$ Mixed Crystal ($Mg_{0.5}Sr_{0.5}FCl_{0.5}Br_{0.5}$ 혼합결정내에 도핑된 $Sm^{2+}$의 광학적 성질 및 영구적 홀생성)

  • 조현갑;장기완;김일곤;조은진;박성태;정용화;서효진
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2002.07a
    • /
    • pp.136-137
    • /
    • 2002

  • 급속도로 발전하는 정보화사회는 정보저장 및 처리에 있어서 고밀도, 대용량의 정보저장 매체를 요구한다. 따라서 3 차원적인 정보저장을 위한 연구가 활발히 진행되고 있으며, 영구적 홀 생성을 이용한 정보의 저장 및 처리도 활발히 연구되고 있는 분야 중의 하나이다. 실질적으로 응용에 필요한 실온에서의 영구적 스펙트럼 홀 생성은 희토류 금속이 첨가된 유리나 결정에서 관측되고 있는데, 이는 대부분 ＋2가 형태로 주입된 희토류 금속의 광학적 성질을 이용하는 것이다. (중략)

  • PDF