• Title, Summary, Keyword: Sequential extraction

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Sequential Extraction of Soil Heavy Metals Aided by Ultrasound Sonication (토양 중금속의 초음파 연속추출)

  • Suh, Jj-Won;Yoon, Hye-On
    • Journal of the Mineralogical Society of Korea
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    • v.23 no.1
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    • pp.85-91
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    • 2010
  • The various forms of heavy metals in soil environments have been studied by sequential extraction method. We tested conventional Tessier sequential extraction and new ultrasound-sonication extraction methods, and compared their extraction efficiency. Total As, Cd, Cu, Pb, and Zn contents of the target soil (NIST SRM 2710 Montana Soil), by three methods (USEPA Method 3050B, KBSI Method, and ultrasound-sonication method) were all consistent with the certified values. Sequential extraction efficiency along with step-wise extraction values was similar in both Tessier method and ultrasound-sonication method. The ultrasound-sonication method took about 3 hours to complete whole procedure while the Tessier sequential extraction method took around 12 hours. Ultrasound-sonication method was estimated as one of the best methods with a relatively short application time and no requirement of high temperature treatment.

Characteristics of Heavy Metals In Contaminated Soil-Metal Binding Mechanism through Sequential Extraction in Soils with Lead and Copper (Sequential Extraction을 이용한 중금속(납.구리)과 토양 결합 기작 연구)

  • 조미영;현재혁;김원석
    • Journal of Korea Soil Environment Society
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    • v.4 no.3
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    • pp.77-84
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    • 1999
  • Sequential extraction was applied to characterize the soil-metal binding mechanism in three kinds of soils contaminated with lead and copper The results showed that soil-metal binding was dependent on soil characteristics and metal species. In Munwha dong soil, lead was mainly carbonate form (37.7%), in agriculture soil was associated with amorphous Fe oxide form (23.9%) and in industry area was associated with exchangeable form (22.9%) Meanwhile for copper. organically bound form represented main fraction in most soil and also carbonate and amorphous Fe oxide form showed high fraction. Crystallized Fe oxide and residuals form of copper showed higher fraction than those of lead. Thus, it can be concluded that copper is bound with soil stronger and more difficult wash out Consequently, this mechanism analysis through sequential extraction can provide useful informations for better soil remediation.

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Verbal Conjunctions in Korean, English and Japanese

  • Oh, Chisung
    • Cross-Cultural Studies
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    • v.32
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    • pp.109-132
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    • 2013
  • This paper compares sequential and non-sequential verbal conjunctions in Korean, English, and Japanese by looking at how sequential verbal conjunction is treated in each language. It frist reviews verbal conjunctions in Korean, where sequential conjunction is treated as subordination and non-sequential conjunction is treated as coordination, and looks at verbal conjunctions in English and Japanese to see whether or not sequential conjunction in those languages is subordination. According to Oh (2010), sequential and non-sequential conjunctions in Korean behave quite differently with respect to the tense and negation in the final conjunct. Also, Cho (1995, 2005) and Kwon (2004) show that syntactic operations such as extraction and scrambling clearly distinguish sequential conjunction from non-sequential conjunction. The purpose of this paper is to see how sequential and non-sequential conjunctions are analyzed in English and Japanese and to compare those languages with Korean, especially focusing on whether or not sequential conjunctions in English and Japanese are treated as subordination. For this purpose, I first investigate how tense and negation, which provided crucial evidence for concluding that Korean sequential conjunction is subordination, is interpreted in sequential and non-sequential verbal conjunctions in English and Japanese. Also, I investigate the syntactic properties of sequential and non-sequential conjunctions with respect to syntactic operations such as extraction and scrambling in those languages. The results of the investigation show that in Japanese, which is considered typologically similar to Korean, the sequential conjunction is a case of subordination, while in English, which is considered typologically different from Korean, both sequential and non-sequential conjunctions are treated as coordination.

The Characteristics of Metals in the Soil Based on the Sequential Extraction With Increasing PH (pH 단계별 증가에 따른 토양 금속의 용출 특성)

  • You, Sun-Jae;Kim, Jong-Gu
    • Journal of Environmental Science International
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    • v.15 no.4
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    • pp.379-384
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    • 2006
  • Eight USA soils were used for this study. The purpose of this study is to illustrate the characteristics of metals in the soil based on the sequential extraction with increasing pH. Extracts were analyzed for metals by ICP-MS and for dissolved organic carbon(DOC). As the pH increasing, the DOC extracted in each increment initially decreased and reached the minimum at pH 3 and then increased substantially at higher pH values. According to the pH increasing, the extraction of Ca, Cu, and Zn were illustrated as L type. It was found that there were strong correlation between the extracted Fe and DOC($r=0.64{\sim}0.97$).

Sequential Extraction을 이용한 Fly ash의 Cd 흡착 양상 평가

  • 이광헌;이승학;이아라;명동일;박준범;김형석
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.376-379
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    • 2004
  • pH has been regarded as a master variable governing the heavy metal sorption on fly ash. However, the chemical constituents in the fly ash could also suggest a potential sorption site for heavy metals. So, in this study sequential extraction method is employed to evaluate the sorption behavior of fly ash for cadmium. Two different fly ashes (S-fly ash, T-fly ash) were obtained from different power plants in Korea. First, cadmium is adsorbed under four different initial pHs. And, Cd sorbed in fly ash was sequentially desorbed following the sequential extraction method suggested by Tessier. In test results, the effect of pH increase was differently exerted in two fly ash. In S-fly ash, exchangeable fraction was dominated in low initial pH, however, as increasing initial pH, the fraction bound to carbonate increased. In the T-fly ash, regardless of initial pH the fraction bound to carbonate was major part of sorption estimated. The fraction bound to Fe/Mn oxide was about 10% in T-fly ash, and 5% in S-fly ash at high pH.

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A study on the Comparison of the Heavy Metal in Abandoned mine Soil by Sequential Extraction Exthaction Methods (폐광산 주변 토양 내 중금속의 연속추출법과 토양오염공정시험기준에 대한 비교 연구)

  • Lee, Jong-Deuk;Kim, Tae-Dong;Jeon, Gee-Seok;Kim, Hee-Joung
    • Journal of Soil and Groundwater Environment
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    • v.16 no.6
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    • pp.95-105
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    • 2011
  • Total extraction method and environmental standards for heavy metals in soils were revised in regulation recently. In case of Area 3, as the law amended, the soil pollution level has gone up to 4 to 13 times higher depending on the type of heavy metal. In this study, it compares the properties of heavy metals of soil by sequential extraction and total extraction methods depending on the analysis method, using the soil around mine. In case of arsenic, the soil pollution level has gone up to 4 times higher, but 6 to 10 times in the sample soil. Also, according to the results of portability evaluation depending on the type of existence form of heavy metal it exists as residual form in mine waste rock, which is less likely to move, while it exists as migrated form in tailing. Therefore, it should be considered to evaluate the soil pollution and decide the contaminated bounds depending on the existence form of heavy metals on soil to restore the polluted soil.

The Determination of Chemical Forms of Heavy Metals in Shooting Area Contaminated Soil Using Sequential Extraction Method (연속추출법을 이용한 사격장 오염토양 중 중금속의 화학적 형태 결정)

  • Moon, Gyeonghye;Park, Hongki;Yoo, Kyoungkeun;Manis Kumar, Jha;Richad Diaz, Alorro;Kim, Ju Yup
    • Journal of Soil and Groundwater Environment
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    • v.20 no.6
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    • pp.111-116
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    • 2015
  • The soil sample obtained from shooting area contaminated with Pb, Cu, and Zn was investigated to determine the chemical forms of heavy metals with Tessier’s sequential extraction method, which is constituted of five fractions such as ‘exchangeable’, ‘bound to carbonate’, ‘bound to oxide’, ‘bound to organic matter’, and residual fractions. The amount of organic matter was measured by loss on ignition (LOI) and then the results of ‘bound to organic matter’ and LOI were compared. The sequential extraction results show that 4.7%-45% of Pb, 6.2%-25.9% of Cu and 3.9%-15.3% of Zn belong to the ‘bound to organic matter’ fraction, but LOI result shows that only 1.0%-2.8% of organic matter exists in the soil sample. In heavy medium separation tests, because Pb and Cu extracted in ‘bound to organic matter’ and residual fractions were removed, the heavy metals in the fractions would exist as heavier forms. These results suggest that the part of heavy metal extracted in ‘bound to organic matter’ fraction would result from the oxidation of metallic forms by hydrogen peroxide and nitric acid used in the fraction, and, consequently, that the ‘bound to organic matter’ fraction should be investigated in detail to determine the removal method and treatment capacity when the Tessier’s sequential extraction method is used to examine heavy metal contaminants resulted from elemental metal like bullets.

Geochemical transport and water-sediment partitioning of heavy metals in acid mine drainage, Kwangyang Au-Ag mine area, Korea

  • Jung, Hun-Bok;Yun, Seong-Taek;Kwon, Jang-Soon;Lee, Pyeong-Koo
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.409-412
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    • 2003
  • Total extraction of stream sediments in the Kwangyang mine area shows their significant pollution with most trace metals such as Cr, Co, Fe, Pb, Cu, Ni, Zn and Cd, due to sulfide oxidation in waste dumps. Calculations of enrichment factor shows that Chonam-ri creek sediments are more severely contaminated than Sagok-ri sediments. Using the weak acid (0.1N HCl) extraction and sequential extraction techniques, the transport and sediment-water partitioning of heavy metals in mine drainage were examined for contaminated sediments in the Chonam-ri and Sagok-ri creeks of the Kwangyang Au-Ag mine area. Calculated distribution coefficient (Kd) generally decreases in the order of Pb $\geq$Al > Cu > Mn > Zn > Co > Ni $\geq$ Cd. Sequential extraction of Chonam-ri creek sediments shows that among non-residual fractions the Fe-Mn oxide fraction is most abundant for most of the metals. This indicates that precipitation of Fe hydroxides plays an important role in regulating heavy metal concentrations in water, as shown by field observations.

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Sequential Separation of Main Components from Chicken Egg Yolk

  • Ahn, Dong-Uk;Lee, Sang-Hyun;Singam, Haribabu;Lee, Eun-Joo;Kim, Jae-Cherl
    • Food Science and Biotechnology
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    • v.15 no.2
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    • pp.189-195
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    • 2006
  • A study was conducted to develop optimal conditions for a large-scale, sequential separation method for value-added components from egg yolk. Starting with liquid egg yolk, immunoglobulin Y (IgY), phospholipids, and neutral lipids were extracted sequentially using water, ethanol, and n-hexane. The remainder was yolk proteins. Adjusting the pH of diluted egg yolk to pH 5.0-5.2 decreased phospholipids content in the supernatant after centrifugation, which was very important for preventing clogging problem of ultrafiltration filters during the subsequent concentration step for IgY separation. Extraction of precipitants after centrifugation with four volumes of 100% ethanol once removed most of the phospholipids and the purity of phospholipids was more than 85% (wt.) after drying. The subsequent extraction of precipitant from ethanol extraction with four volumes of hexane 3 times removed neutral lipids almost completely and resulted in a high protein product with minimal lipids. The sequential separation method is considered to be advantageous for large-scale separations of many valuable components from egg yolk.

Evaluation of Sequential Extraction Techniques for Selected Heavy Metal Speciation in Contaminated Soils

  • Lee, Jin-Ho;Doolittle, James J.;Oh, Byung-Taek
    • Korean Journal of Environmental Agriculture
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    • v.25 no.3
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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.