Extraction of heavy metals in contaminated soils with EDTA solution and their recovery technique.

作者：Yang Ren-bin · 发表于：China Environmental Science · 年份：2003 · 被引用次数：4 · 研究领域：Environmental Quality and Pollution

The technique of separating heavy metals in ethylenediamine-tetraacetic acid (EDTA) solution was studied and used for remediation of soils pollution. EDTA solution could extract effectively the heavy metals in soil. Na2S could separate sedimentarily Cd, Cu, Pb in EDTA solution with efficiency over 99%; but Zn precipitation required the addition of Ca(OH)2. Ca2+ introduced into the reaction system had no influence on extraction of heavy metals and EDTA recovery. Successive extractions process enhanced the removal rate of heavy metals in contaminated soils. The removal rates of Cd and Pb accumulation in soil reached 75.6% and 72.5% respectively. Successive use of recovered EDTA for ten times, EDTA losses were about 30%. The sulfide precipitates obtained had high concentrations of heavy metals and could be treated or recovered conveniently.