Extraction, Recovery, and Biostability of EDTA for Remediation of Heavy Metal-Contaminated Soil

Recycling of complexometric extractants to remediate a soil contaminated with heavy metals

“…Calcium hydroxide [Ca(OH)2] enhanced this reaction by providing Ca +2 to compete for EDTA ligand by displacing metal from its chelator complex. Other research was performed to separate Pb, Zn and Cu from their EDT A complexes, with the result that >99%, 70-74%, and 93-98% respectively of these metals were recovered after this treatment (40). This research also demonstrated that higher concentrations of EDT A improved soil washing performance because more washing cycles could be performed with reclamation ofEDTA after addition ofNa2S and Ca(OH)2 at a pH of 10.…”

“…It is both an industrial and analytical reagent because of its ability to complex with many divalent and trivalent metal cations that are characterized by up to a hexadenate primary co-ordination sphere (six bonds). EDTA has been applied in various remediation treatments and has demonstrated a high affinity for both exchangeable and oxide metals within polluted soils (38,40). It is currently scheduled by EP A for acute toxicity evaluation.…”

“…Research has demonstrated that chelating extraction is viable for soil remediation but that only moderate strength chelators can be recovered (46). However, there are also a 30 limited number of studies that have indicated that strong chelating reagents, like EDT A, that are not biodegradable, can be recovered and recycled (38,40).…”

Assessment of EDTA heap leaching of an agricultural soil highly contaminated with heavy metals

“…Most studies of EDTA washing have focused on the effectiveness of toxic metal removal from soils at industrial sites and there are few reports in the literature on studies dealing with the ecological toxicity of agricultural soils after remediation (Jelusic et al, 2014 EDTA is a biologically stable chelant and it is very difficult for unacclimated microbial cultures to degrade (Hong et al, 1999). After EDTA leaching some metal-EDTA complexes are retained in the soil by the formation of bonds with soil iron oxides and especially goethite (Nowack and Sigg, 1996).…”

Effects of a Chelate (DTPA) on Cucumber Growth and Soil Chemical Properties in Nutrient-accumulated Soil of Polytunnel Greenhouse

“…킬레이트제는 자연상태에서 존재하는 물질이며 (Abdulla and Smith, 1963), 금속 이온과 2자리 이상으로 배위결합을 하여 고리구조의 모양을 만드는 리간드을 말한다 (Tuntiwiwut, 1982 (Lindsay and Norvell, 1978)과 중금속의 오염물질 을 제거 (Hong et al, 1999;Cao et al, 2007;Palmaa et al, 2007)하는데 주로 사용되었으며, 식물의 미량원소를 공 급하는 데 많이 이용되었다 (Weinstein et al, 1954;Brown et al, 1960;Abdulla and Smith, 1963;Wallace, 1963, Wallace et al, 1974.…”