• 한국농공학회논문집
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• 제48권1호
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• pp.3-10
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• 2006

The chemical fractions of heavy metals were investigated in the soils of reclaimed and natural tidelands of southwest coastal area of Korea. The distribution pattern of each heavy metal in different fractions was in the order: 1) Cu : organic bound > organic complex > residual > exchangeable = water soluble. 2) Cr : residual > organic bound > organic complex > water soluble > exchangeable. 3) Pb : organic bound > residual > organic complex > water soluble > exchangeable. 4) Cd residual > organic bound > organic complex > water soluble = exchangeable. 5) Zn : organic bound > residual > organic complex > water soluble > exchangeable. The content of residual Zn showed positive correlation with organic matter content but organic bound Zn showed negative correlation with CEC. The content of residual and exchangeable Cd showed highly positive correlation with organic matter content but residual, organic bound, and exchangeable Cd showed negative correlations with CEC. Water soluble Pb showed positive correlation with CEC but organic bound Pb showed negative correlation with CEC.

• 한국토양비료학회지
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• 제44권4호
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• pp.591-596
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• 2011

The applications of chemical fertilizers and various types of organic materials may cause heavy metal accumulation in soil. In this study, we conducted to investigate the relationship between the different chemical forms of heavy metals such as Cr, Cd, Pb, Cu, Ni, and Zn retained in soil and the metal concentrations in Korean raspberry plant. Forty five soil samples were collected from 2 to 6 years old Korean raspberry cultivation fields (RCFs), Gochang, Korea, to determine total, exchangeable (1.0 M $MgCl_2$-extractable), DTPA-extractable metal contents. The leaves and fruits of raspberry plant were sampled at harvest stage. Total metal contents in soils ranged from $0.87mg\;kg^{-1}$ to $66.82mg\;kg^{-1}$. Exchangeable and DTPA-extractable metals ranged between 0.02 and $0.67mg\;kg^{-1}$ and between $0.05mg\;kg^{-1}$ and $7.07mg\;kg^{-1}$, respectively. The metal concentrations in the plant leaf and fruit determined on a dry-basis were between $1.30mg\;kg^{-1}$ and $38.82mg\;kg^{-1}$ and between $0.05mg\;kg^{-1}$ and $21.51mg\;kg^{-1}$, respectively, but Cd and Pb were not detected in the leaf. The total, exchangeable, and DTPA-extractable contents of the metal ions in soil were directly correlated one another, but the contents of different metals in the different fractions were inversely correlated in general. Most of total and DTPA-extractable metals in the soil were directly correlated with the contents of the same metals in the plant, whereas exchangeable metals in the soil were not statistically correlated with the same metals in plants. Thus, we concluded that the metal contents in the raspberry field soils were much lower thanthe levels of Soil Contamination Warning Standard (SCWS), and the plant metal concentrations were also less than the maximum permissible limits. The total and DTPA-extractable metals in the soil were closely related to the metal concentrations in the plant.

• 한국토양비료학회지
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• 제45권6호
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• pp.920-924
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• 2012

This study was performed to estimate total contents of arsenic (As) by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines. The soil was collected from paddies near abandoned mines. Soil pH, electrical conductively (EC), organic mater (OM), available phosphorus ($P_2O_5$), and exchangeable cations (Ca, K, Mg, Na) were measured. Total contents of As and extractable contents of metals were analyzed by ICP-OES. From stepwise analysis, it was showed that the contents of extractable As, available phosphorus, extractable Cu, exchangeable K, exchangeable Na, and organic mater significantly influenced the total contents of As in soil (p<0.001). The multiple linear regression models have been established as Log (Total-As) = 0.741 + 0.716 Log (extractable-As) - 0.734 Log (avail-$P_2O_5$) + 0.334 Log (extractable-Cu) + 0.186 Log (exchangeable-K) - 0.593 Log (exchangeable-Na) + 0.558 Log (OM). The estimated value in total contents of As was significantly correlated with the measured value in soil ($R^2$=0.84196, p<0.0001). This predictive model for estimating total As contents in paddy soil will be properly applied to the numerous datasets which were surveyed with extractable heavy metal contents based on Soil Environmental Conservation Act before 2010.

• 한국환경농학회지
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• 제25권3호
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• pp.236-246
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• 2006

In this study, we give insight into questionable results that can be encountered in the conventional sequential extraction of heavy metals (Cd, Cu, and Zn) from soils. Objectives of this study were to determine the extraction variability of exchangeable (EXC)-metals as using six different EXC-extractants commonly accepted, and to investigate selectivity problems with carbonates bound (CAB)-metal fraction, a buffered acetate (1.0 M NaOAc; pH 5.0) extractable-metal fraction, leading to erratic results in especially non-calcareous soils. The contents of EXC-metals were markedly varied with the different extractability of various EXC-metal extractants used. The contents of EXC-Cd fraction were ranged from 2.0 to 74.3% of total Cd content in all of the metal spiked soils studied. The contents of EXC-Zn fraction extracted with the different EXC-extractants were varied with soil types, which were from 0.4 to 3.9% of total Zn in the calcareous soils, from 7.6 to 17.9% in the acidic soil, and from 13.6 to 56.8% in the peat soil. However, the contents of EXC-Cu fraction were relatively similar among the applications of different EXC-meal extractants, 0.2 to 2.1 % of total Cu, in all soils tested. Also, these varied amounts of EXC-metal fractions, especially Cd and Zn, seriously impacted the contents of subsequent metal fractions in the procedure. Furthermore, the CAB-Cd, -Cu, and -Zn fractions extracted by the buffered acetate solution were in critical problem. That is, the buffered acetate solution dissolved not only CAB-metals but also metals that bound or occupied to subsequent fractions, especially OXD-metal fraction, in both calcareous and non-calcareous soils. The erratic results of CAB-fraction also seriously impacted the amounts of subsequent metal fractions. Therefore, the conventional sequential extraction should be reconsidered theoretically and experimentally to quantify the target metal fractions or might be progressively discarded.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권6호
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• pp.169-178
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• 2016

The Standards, Measurement and Testing Programme (SM&T-formerly BCR) extraction procedure was applied to fractionate Cr, Cu, Ni, Pb and Zn in 23 top soil samples into: (i) exchangeable phase; (ii) reducible phase; (iii) oxidisable(sulfides and organics bound) phase; and (iv) residual phase. Fractions of Cr and Ni were in the order of residual > oxidisable > reducible > exchangeable phase. The oxidisable phase was identified as dominant for Cu and Pb. Zn had the highest ratio of exchangeable phase in comparision to the other metals. The bioavailability and mobility were assessed to be the greatest for Zn, followed by a decreasing order of Pb, Cu, Ni and Cr. All metal average concentrations in topsoil samples was higher in industrial sites than in agricultural sites. Our results revealed higher concentrations in topsoil samples (0~15 cm) than in sub soils (15~30 cm, 30~60 cm) for most metals at six sites (No. 5, 6, 17, 19, 20, 23). The fractions of exchangeable, reducible ad oxidisable phases showed relatively high correlation with soil pH, Fe/Mn oxide concentrations and organic matter contents, respectively.

• 한국광물학회지
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• 제10권2호
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• pp.139-147
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• 1997

The Janghang smelter is the first lead, zinc and copper smelting facility in Korea which was operated for a half century from 1936 to 1989. The clay minerals and their heavy metal association in the soil profile around the smelter have been studied using XRD, EPMA, SEM-EDS, TEM, EPR and sequential extraction techniques. The soils in A horizon are highly acidic showing pH 4.45. The pH is going up with increasing depth. They have residual water contents of 1.18-1.51 wt%, loss on ignition of 6.32-7.79 wt%, and carbon contents of 0.08-0.88 wt%. Soils consist of quartz, feldspar, muscovite, kaolinite, vermiculite, biotite, chlorite, goethite and hematite in the decreasing abundance. The contents of clay minerals, especially vermiculite and chlorite, decrease with increasing depth. Sequential extraction experiments for the profile samples show that heavy metals (Zn, Cu, Pb, Cd) are highly concentrated in the A horizon of the soil profile as water-extractable (mostly amorphous), MgCl2-extractable (exchangeable in clay minerals), and organic phases. The heavy metal contents decrease with increasing depth. It suggests that the heavy metals are mainly associate with clay minerlas in an exchangeable state. It is also noted that heavy metals are highly concentrated in the manganese and iron oxide phases.

• 대한환경공학회지
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• 제22권7호
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• pp.1357-1364
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• 2000

본 연구는 소각 비산재의 물리 화학적 특성이 중금속의 용출 거동에 미치는 영향을 알아보고자 수행되었다. 영향인자로는 비산재의 pH, CEC, 입자크기, 연속추출방법에 의해 분류된 중금속의 존재형태 중에서 exchangeable fraction을 고려하였다. KSLT법에 의한 중금속의 용출율은 pH에 크게 의존적이고 원소에 따라 차이를 보였다. 카드뮴과 구리의 용출율은 pH가 증가함에 따라 감소한 반면, 납과 아연은 중성 또는 강알칼리성 조건에서 증가하는 것으로 나타났는데, 중금속의 용출 거동이 용해도에 의해 제한됨을 나타내 준다. CEC가 중금속의 용출율에 미치는 영향은 pH와 비슷한 것으로 나타났다. 비산재의 입자크기 중에서 $D_{10}$은 KSLT법에 의한 중금속의 용출량과 음의 상관성을 나타내었다. Exchangeable fraction의 경우는 비산재의 CEC 값이 40 meq/100g 미만인 시료는 선형관계에 있지만, 그 외의 CEC 값에서는 비선형관계를 보여주었다.

• 한국토양환경학회지
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• 제4권3호
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• pp.77-84
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• 1999

본 논문에서는 고농도의 중금속 (납, 구리)으로 오염된 세 가지의 토양을 대상으로 sequential extraction 방법을 사용하여 토양과 중금속의 차이에 따른 결합 특성을 밝혀내고자 하였다. 고농도의 납과 구리로 오염된 토양을 형태별로 추출하였을 때 토양의 특성과 중금속의 종류에 따라 다른 결과를 보였다. 납은 문화동 토양에서는 Carbonate 형태가 37.7%로 가장 높았고 농토는 Amorphous Fe oxide 형태가 23.9%, 공단 토양에서는 Exchangeable 형태가 22.9%로 나타났다. 이에 비하여 구리는 세 가지 토양에서 공통적으로 Organically bound 형태가 농토에서 26.1%, 문화동 토양은 20.4%. 공단 토양에서는 24.1%로 높게 나타났고 Carbonate 형태와 Amorphous Fe oxide형태의 비율도 높게 나타났다. 또한 Crystallized Fe oxide 형태와 Residuals 형태도 납보다 높은 비율을 나타냄으로서 구리가 납보다는 토양과 강한 결합을 형성하는 것으로 생각된다. 이러한 토양과 중금속의 결합 특성은 오염 토양의 복원시 유용한 자료가 될 수 있다.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2570-2575
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• 2021

The exchange behaviors of hydrogen isotopes between protonated lithium metal compounds and deuterated water or tritiated water were investigated. The various protonated lithium metal compounds were prepared by acid treatment of lithium metal compounds with different crystal structures and metal compositions. The protonated lithium metal compounds could more effectively reduce the deuterium concentration in water compared with the corresponding pristine lithium metal compounds. The H⁺ in the protonated lithium metal compounds was speculated to be more readily exchangeable with hydrons in the aqueous solution compared with Li⁺ in the pristine lithium metal compounds, and the exchanged heavier isotopes were speculated to be more stably retained in the crystal structure compared with the light protons. When the tritiated water (157.7 kBq/kg) was reacted with the protonated lithium metal compounds, the protonated lithium manganese nickel cobalt oxide was found to adsorb and retain twice as much tritium (163.9 Bq/g) as the protonated lithium manganese oxide (69.9 Bq/g) and the protonated lithium cobalt oxide (75.1 Bq/g) in the equilibrium state.

• 한국지반환경공학회 논문집
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• 제11권11호
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• pp.63-75
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• 2010

중금속으로 오염된 부지는 다양한 공법으로 복원이 가능하나 오염부지가 비교적 넓은 경우 중금속을 부지로부터 제거하는 적극적 공법은 기술적 어려움과 비용의 문제로 쉽게 사용할 수 없다. 그러므로 토양에서 중금속의 용출을 차단 및 지연하는 안정화 공법이 보다 현실적이라 할 수 있다. 본 연구에서는 국내의 비교적 큰 규모의 중금속 오염토양인 제련소 오염토양을 대상으로 magnetite, hematite, zeolite-A, zeolite-X, zeolite-Y, zinc oxide, calcium oxide, carbon trioxide, manganese oxide, manganese dioxide, fish bone, sodium phosphate 등의 다양한 안정화제의 적용성실험을 수행하였다. 비소, 납, 구리, 니켈, 아연 등의 다중 중금속으로 오염된 토양의 경우 1종의 안정화제로 안정화가 어려우며 기존 연구에서 보고된 특정 중금속의 안정화에 우수한 성능을 갖는 안정화제의 경우에도 다른 중금속의 안정화에 기여하지 못하거나 용출을 촉진하는 경향을 보였다. 시간이 경과함에 따라 안정화 효율이 증가하였다. 니켈과 납의 경우 calcium oxide, carbon trioxide, manganese oxide 등의 안정화제가 효과가 있으며 특히 연속추출에서 물에 의한 추출부분에서 안정화 효율이 높았다. 구리의 경우 manganese oxide, zeolite 등이 효과가 크며 연속추출에서 exchangeable 추출부분에서 안정화 효율이 높았다. 비소의 경우 magnetite에 의한 안정화 효과를 보이며 대부분의 metal oxide와 phosphate 에 의해 용출이 촉진되는 부작용을 보였다. 그러므로 다양한 중금속으로 오염된 토양의 경우 2종 이상의 안정화제를 사용하여야 하며 역효과를 일으키는 안정화제의 사용을 배제하고 중금속의 농도에 따라 사용량 및 안정화 기간을 달리하여야 할 것으로 판단된다.