• Title/Summary/Keyword: 희토류 원소

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Assessments of Dissolved Rare Earth Elements and Anthropogenic Gadolinium Concentrations in Different Processes of Wastewater Treatment Plant in Busan, Korea (부산 하수처리장에서 공정별 용존 희토류 원소의 농도 및 인위적 기원 가돌리늄의 배출량 평가)

  • Lim, Ijin;Ryu, Jong-Sik;Lee, Joonyeob;Lee, Jun-Ho;Cho, Hyung-Mi;Kim, Taejin
    • Journal of the Korean earth science society
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    • v.43 no.2
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    • pp.303-311
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    • 2022
  • Gadolinium, commonly used as a contrast agent for magnetic resonance imaging (MRI), is discharged into aquatic environments without removal after treatment in wastewater treatment plants (WWTPs) because of its high stability. In this study, we collected water samples from Suyeong WWTP, Busan, to investigate the dissolved rare earth element (REE) removal capacity of each wastewater treatment process and to evaluate the discharge of anthropogenic Gd (Gdanth) from effluents. As wastewater passed through each stage of treatment, the concentrations of light REEs (La-Eu) decreased, whereas those of heavy REEs (Tb-Lu) were relatively consistent. Negative Sm anomalies (<1) were observed in several samples, indicating that Sm can be removed by adsorption onto particles or phosphate during the biological removal process. Positive Gd anomalies (149±50, n=9) were observed in all samples. The ratios of Gdanth concentrations to measured Gd concentrations in all wastewater treatment processes were higher than 97%. This indicates that Gdanth was discharged to the Suyeong River without removal during the wastewater treatment process. Considering the daily treatment capacity in each process, the total flux of Gdanth was estimated to be 259 mmol/day. Our results suggest that mid- and/or long-term monitoring of Gd is needed because Gdanth is continuously discharged into Suyeong Bay through WWTPs.

지질특성에 따른 균열면 대수층에서의 Eu의 거동: 액티나이드원소의 유사체로서의 회토류원소

  • 이승구;김용제;김건한
    • Proceedings of the KSEEG Conference
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    • 2003.04a
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    • pp.112-115
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    • 2003
  • 희토류원소는 원자번호 57의 La으로부터 원자번호 71의 Lu까지의 원소군으로서, 지난 40여년간 지구화학 및 우주화학의 연구분야에서 상당한 관심을 받아왔다 (Masuda et al., 1973; Taylor and McLennan, 1985: Johannesson et at., 1997). 최근에는 지하수, 호소와 같은 육상수에서의 희토류원소의 농도가 그들의 지구화학적 진화에 영향을 주는 과정의 잠재적인 지시자로서 주목을 받고 있다 (Sholkovitz, 1992; Johannson et at., 1997). (중략)

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Rare Earth Element Analysis with Chromatography-Inductively Coupled Plasma Atomic Emission Spectrometry and the Comparison of Cross Flow and Ultrasonic Nebulizers (크로마토그래피-유도 결합 플라스마 원자방출 분광법을 이용한 희토류 원소들의 연속적 분석 및 직교형과 초음파분무기의 비교)

A study on the Determination and Solvent Extraction Efficiencies of Rare Earth Elements by TBP and Nitrate Salt (TBP와 질산염을 이용한 희토류원소의 용매추출과 분석에 관한 연구)

  • Lee, Jung Min;Lee, Yong Ju;Kim, Sook Young;Kim, Young Man;Choi, Beom Suk
    • Analytical Science and Technology
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    • v.14 no.2
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    • pp.103-108
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    • 2001
  • Rare earth elements(REE) were separated by solvent extraction with tri-n-butyl phosphate(TBP) and $NaNO_3$, followed by back extraction with water. The method was applied to the determination of REE to circumvent the spectral interferences of ICP-AES analysis. The effects of the $NaNO_3$ concentration and the addition of hydrophobic solvents on the extraction efficiencies were investigated. Increases of the $NaNO_3$ concentration enhanced the extraction efficiencies of REE, and more than 95% recoveries were obtained at 5M of $NaNO_3$ concentration. On the other hand, addition of hydrophobic solvents lowered the extraction efficiencies. The method was applied to determine the REE in the monazite sample. But the precisions of the analytical results were more than 20%.

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Element Mobility during the Weathering of Granitic Gneiss in the Yoogoo Area, Korea. (유구지역 화강암질 편마암의 풍화작용에 따른 원소의 거동)

  • 이석훈;김수진
    • Journal of the Mineralogical Society of Korea
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    • v.14 no.1
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    • pp.39-51
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    • 2001
  • 공주군 유구면 일대의 화강암질 편마암의 풍화작용에 따른 원소의 거동과 pH와 이차광물과의 관계를 XRF, ICP-AES, ICP-MS를 이용한 원소분석결과를 통하여 검토하였다. 이 지역의 암석은 pH6 내외의 산성환경, 침철석, 아나타제와 같은 다양한 이차광물을 생성하면서 심각한 화학조성의 변화를 초래했다. 주원소의 화학조성을 이용한 풍화지수는 토양층에서 79~88로 모암 중의 사장석이 용해되고 흑운모가 변질되어 캐올리광물의 생성이 활발한 방향으로 풍화작용이 진행되었다. 지표층으로 가면서 Al에 대한 주 원소의 거동은 Si, Ca, Na, K, P가 감소하고 Fe, Ti, Mn이 증가하는 경향을 보이며 pH가 낮은 풍화단면에서 주 원소의 변화량이 더 크다. 이 풍화대에서 Mg은 거의 일정하다. Li, As 모든 전이원소는 pH가 감소함에 따라 증가하며 특히 이들 원소는 Fe의 함량과 비례해서 증가해 침철석과 공침하였거나 표면에 흡착되어 있는 것으로 보인다. Ga은 Fe와 비례하기는 하지만 변화량은 전 풍화단면에서 일정하다. Zr, Mo, Sn, Cd은 pH에 변화에 상관없이 일정한 반면에 Rb, Sr, Ba, Y, Pb, Th, U 등은 감소하는 경향을 보인다. 특히 Rb 과 Sr은 Ca에 비례해서 감소한다. 희토류원소는 전 풍화단면에서 감소하는 경향을 보이는데 $Al_2$$O_3$에 대한 상대적인 변화량을 보면 경희토류원소는 사프롤라이트(saprolite)하부와 상부에서 부화되어 있고 중부 사프롤라이트와 토양층에서 감소하는 반면에 중희토류원소는 사프롤라이트 하부와 상부에서 감소하고 중부사프롤라이트 및 토양층에서 부화되는 경향을 보인다. 전반적으로 희토류원소의 원자번호가 클수록 손실율이 커진다. 이 풍화단면에서 원소의 거동은 각 풍화층의 pH와 생성된 이차광물의 조성에 지배를 받았다.

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Retention Behavior of Lanthanide Complexes with $\alpha$ -hydroxyisobutyric Acid on Cation Exchanger (양이온 교환체에서 희토류원소와 $\alpha$-Hydroxyisobutyric Acid 착물들의 머무름 거동에 관한 연구)

  • Jo, Gi Su;Han, Seon Ho;Seo, Mu Yeol;Eom, Tae Yun;Kim, Yeon Du
    • Journal of the Korean Chemical Society
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    • v.34 no.6
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    • pp.582-592
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    • 1990
  • Retention behavior of lanthanide-$\alpha$HiBA complexes was studied on the cation exchanger (LC-18 coated with $C_{20}H_{41}SO_4^-$). An equation predicting retention of lanthanides in isocratic or gradient elution with sodium ion and $\alpha$-HiBA concentration was derived from ion exchange equilibria of metal-ligand complex system, respectively. The relations between log k' and log [Na$^+$] /log [$\alpha$-HiBA) showed non-linearity in isocratic elution. In gradient elution a good linearity between log k' vs log R was obtained. The values of slopes (log k / log R) gave good agreements between calculation and experiment. Individual capacity factors ($k'_{Ln}^{3+}, k'_{LnL}^{2+}, k'{LnL2+}) and stability constant (${\beta}_1$, ${\beta}_2$, ${\beta}_3$) of lanthanide-$\alpha$HiBA complexes were calculated by the non-linear least square fittings using the retention equation. The correlation coefficients of lanthanides were shown better than 0.9996 between experiment and calculation.

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Geochemical Implication of Rare Earth Element from Yellow sand (Asian Dust) at Daejeon Area, Korea: A Preliminary Study for Clarifying Source Area of Yellow Sand (대전지역 황사(아시아 먼지)내 희토류원소 분포도의 지구화학적 특성-근원지 규명을 위한 초기연구)

  • Lee, Seung-Gu;Youm, Seung-Jun
    • The Journal of the Petrological Society of Korea
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    • v.17 no.1
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    • pp.44-50
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    • 2008
  • A geochemical technique based on rare earth element geochemistry was used to clarity the source of the Asian dust (Yellow sand) in the Daejeon area. The Asian dusts were collected 4 times during 31th March- 2nd April and 25th May-27th May 2007. The Yellow sand shows PAAS (Post Archean Australian Shale)-normalized REE pattern of the flattened LREE and slightly depleted LREE without Eu anomaly, whereas the Daejeon soil has slightly enriched LREE and depleted HREE with negative Eu anomaly. Our results show that REE patterns of the Asian dust are LREE-flattened similar to those of the sediment from the south-eastern part of Ordos desert. This suggests that Asian dust in the Daejeon area might be derived from the south-eastern part of Ordos desert.

Study on the Precision Analysis of Lanthanides by Atomic Emission Spectroscopy (I). Separation of Rare Earth Elements Using Ln-EDTA Eluent (원자발광광도법에 의한 란탄족 원소의 정밀분석에 관한 연구 (제 1 보) 희토류-EDTA 용리액에 의한 희토류 원소의 분리 회수)

  • Cha Ki-Won;Oh Jin-Hee;Ha Young-Gu;Kim Ha-Suck
    • Journal of the Korean Chemical Society
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    • v.36 no.5
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    • pp.692-696
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    • 1992
  • $NH_4^+ form cation exchange resin was used to separate one rare earth element from the rare earth mixture solution using Ln-EDTA eluent. Rare earth mixture solution was passed through the resin bed and eluted with 0.1M La-EDTA solution as an eluent. In here all the rare earth element except lanthanum ion are eluted and lanthanum ion absorbed in resin bed is eluted using 0.1M EDTA solution. If Ce-EDTA solution instead of La-EDTA solution was used as an eluent, all the rare earth element except cerium ion are eluted and cerium ion is eluted with 0.1M EDTA solution. This method can be applied to separate the individual rare earth element from the mixture. The separation mechanism is as follows: Absorption : 3RNH_4 + Ln^{3+} = R_3Ln + 3NH_4^+, La-EDTA elution : R_3Ln + La-Y- = R_3La + Ln-Y-, EDTA elution : R_3La + HY^3- = La_-Y + RH + 2R^-.$

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Geochemical Composition of the Continental Crust in Korean Peninsula (한반도 지각암류의 지구화학적 특성)

  • Lee, Seung-Gu;Kim, Dong-Yeon
    • The Journal of the Petrological Society of Korea
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    • v.21 no.2
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    • pp.113-128
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    • 2012
  • The chemical composition of the continental crust play an important role in understanding of crustal formation and evolution and quantifying other processes taking place within continental crust. We summarized geochemical data reported in the previous literature for the crustal rocks in the Korean Peninsula and divided their chemical composition into geologic time scale. In the variation diagram normalized by average composition of the upper crustal rocks, the geochemical characteristics of the upper crust during Triassic period is different from those of the upper crustal rocks after Jurassic period or before Precambrian. However, the geochemical characteristics of the Jurassic and Precambrian period are similar each other. Our summarized data indicate that the source material of Triassic upper crust may be different from that of Jurassic or Precambrian upper crust.

Sorption Behavior of $^{241}Am,\;^{152}Eu,\;^{160}Tb\;and\;^{60}Co$ in the Geological Materials: Eu as an Optimum Analogue for Fate and Transport of Am Behavior in Subsurface Environment (지질매체내에서의 $^{241}Am,\;^{152}Eu,\;^{160}Tb,\;^{60}Co$의 흡착특성비교: 지표지질내에서의 Am의 거동특성을 위한 최적 유사체로서의 Eu)

  • Lee, Seung-Gu;Lee, Kil-Yong;Cho, Soo-Young;Yoon, Yoon-Yeol;Kim, Yong-Je
    • Economic and Environmental Geology
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    • v.40 no.4
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    • pp.361-374
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    • 2007
  • Rare earth elements(REEs) have been used as an useful tool in understanding the various geological processes such as evolution and differentiation in the crust. The REEs also have been used as an analog of actinides for radioactive wastes at the water-rock interactions. Using physicochemical properties of the REEs and actinides, we have shown that Eu is an optimum analogue for understanding the behavior of Am in subsurface environments. Factors affecting sorption behavior of radioactive nuclides in groundwater were investigated by batch experiments. Four nuclides such as $^{241}Am,\;^{152}Eu,\;^{160}Tb\;and\;^{60}Co$ were selected to test our hypothesis, and $^{160}Tb$ and $^{60}Co$ were specifically used to compare to the sorption behavior between $^{241}Am-^{152}Eu$ and other radioactive nuclides. Four different rock samples and one groundwater were used in the batch experiments where solution pH for all experiments was fixed at 5.5. Our results demonstrate that $^{241}Am,\;^{152}Eu,\;and\;^{160}Tb$ show similar sorption behavior whereas $^{60}Co$ is different in sorption behavior at the mineral-water interface, suggesting that the sorption behavior of $^{60}Co$ is affected by different rock types. Our results also show that 1) Eu in REEs is optimum analogue of fate and transport of Am in subsurface environments, and 2) mineral compositions such as $SiO_2,\;TiO_2,\;P_2O_5$ and distribution of REEs such as Eu anomaly play key roles in affecting sorption behavior of radioactive nuclides even though physicochemical properties of geological materials such as specific surface area and cation exchange capacity can not be ruled out.