Soil Washing Technology for Removing Heavy Metals from a Contaminated Soil: A Case Study

Abstract

Although EDTA solution is considered an efficient soil washing liquid for extraction of heavy metals from soils, its low biodegradability may alter soil properties and suppress plant growth. Alternatively, chlorides are safer and cheaper washing liquids than EDTA. To investigate the efficiency of chlorides versus EDTA in extracting heavy metals from contaminated soils, soil samples (pH 6.14±0.11) were collected from a local agriculture soil in Australia, artificially contaminated with either Pb, Cd or Cr at three different levels of 200, 400 and 600 mg kg-1, and then packed in capped plastic flasks. Batch washing techniques were followed with either EDTA or FeCl3 solutions (prepared at 4 dif..