CAJ | 학술논문

采用3种有机配体(EDTA、DTPA、NTA)对来自南京市汤山废弃铜矿区的重金属污染土壤进行浸提,并且通过改进的BCR连续提取法分析了残留土壤样品中重金属元素以及Fe、Al形态.结果表明,有机配体的存在导致Cu、Zn、Ca、Mg、Mn元素的浸提率明显增加.其中Cu提取率分别为对照的8.08(EDTA)、8.15(DTPA)和5.40(NTA)倍,Zn的提取率分别为对照的10.5(EDTA)、5.75(DTPA)和3.63(NTA)倍.EDTA和DTPA对矿物元素的溶出作用高于NTA.配体对Mg的影响较其他元素小.EDTA、DTPA和NTA对重金属元素的4种形态均有浸提作用,配体的提取对酸溶,可交换态及可还原态影响较大.对于Zn而言,各有机配体处理可还原态下降的倍数最多,其次是酸溶厂可交换态以及可氧化态;对于Pb而言,各有机配体的处理导致酸溶厂可交换态下降的倍数最多;对于Cu而言,EDTA处理组酸溶,可交换态和可还原态下降倍数较多分别为对照组的71.8%和71.9%,DTPA处理组可还原态下降倍数较多为对照组的75.1%.有机配体处理导致酸溶厂可交换态Fe、Al含量的下降.
채용3충유궤배체(EDTA、DTPA、NTA)대래자남경시탕산폐기동광구적중금속오염토양진행침제,병차통과개진적BCR련속제취법분석료잔류토양양품중중금속원소이급Fe、Al형태.결과표명,유궤배체적존재도치Cu、Zn、Ca、Mg、Mn원소적침제솔명현증가.기중Cu제취솔분별위대조적8.08(EDTA)、8.15(DTPA)화5.40(NTA)배,Zn적제취솔분별위대조적10.5(EDTA)、5.75(DTPA)화3.63(NTA)배.EDTA화DTPA대광물원소적용출작용고우NTA.배체대Mg적영향교기타원소소.EDTA、DTPA화NTA대중금속원소적4충형태균유침제작용,배체적제취대산용,가교환태급가환원태영향교대.대우Zn이언,각유궤배체처리가환원태하강적배수최다,기차시산용엄가교환태이급가양화태;대우Pb이언,각유궤배체적처리도치산용엄가교환태하강적배수최다;대우Cu이언,EDTA처리조산용,가교환태화가환원태하강배수교다분별위대조조적71.8%화71.9%,DTPA처리조가환원태하강배수교다위대조조적75.1%.유궤배체처리도치산용엄가교환태Fe、Al함량적하강.
Metals in polluted soils from disused copper mining area were extracted using EDTA, DTPA and NTA. After extraction, metals ( Cu, Zn, Pb, Fe and Al) in different phases were analyzed by modified BCR sequential extraction procedure. The extraction efficiency of met-als increased evidently at the presence of EDTA, DTPA and NTA. The extraction efficiency was 8.08(EDTA), 8.15(DTPA) and 5.40(NTA) times of the control for Cu, and 10.5(EDTA), 5.75(DTPA) and 3.63(NTA) times of the control for Zn. Mg was only slightly affected compared to other elements, and its extraction efficiency was 1.28(EDTA), 1.21 (DTPA) and 1.12(NTA) times of the control. However, Mn and Fe were impacted severely, and the extraction efficiency of Fe was 11.3(EDTA), 21.7(DTPA) and 2.33(NTA) times of the control. All the fractions tested could be affected by the extraction using EDTA, DTPA and NTA. Exchangeable fraction and reducible fraction of the metals (Cu, Zn, Pb) significantly reduced due to the extraction with the three ligands. After extraction, reducible fraction of Zn was only 19.9%(EDTA), 18.6%(DTPA) and 22.3%(NTA) of the control and exchangeable Pb was 64.3%(EDTA),49.5%(DTPA) and 82.4%(NTA) of the control. For EDTA and DTPA treatment, reducible fraction of Cu was only 71.9% and 75.1% of the control. Extraction with the three ligands also re-sulted in the decrease of the contents of exchangeable/acid-extractable Fe and AL The extraction using organic ligands( EDTA, DTPA and NTA) resulted in the increase of the dissolution of both the target heavy metals (Cu, Zn, Pb) and other metals (Al and mineral elements - Ca, Mg, Mn, and Fe), and the extraction decreased the bioavailable fractions of the heavy metals.