ABSTRACT
Soil contamination caused by heavy metals has become a serious environmental and health-related problem to human. Copper (Cu) is essential to human and plants in appropriate amount but toxicant if excessive. Although soil washing has been developed for a long time for heavy metal remediation, there are few studies focusing on Cu, especially in the case of extreme concentration of metal and dissolved organic matters (DOM). Thus, based on the literature reviews about soil washing, this study tried to find out the practical and effective methods to achieve remediation for Cu pollution in different situations of various soil texture and pollution concentrations. Different Cu polluted soils in industrial ground were sampled in Shanghai for experiments. Considering washing agents, washing duration time, liquid to solid ratio, combinations of different agents and oxidation pretreatment, the optimal soil washing conditions were decided. Results showed that washing agents and soil texture seriously affected the efficiency of soil washing. 0.05 mol/L Ethylenediamine tetraacetic acid (EDTA) or 0.1 mol/L FeCl3 combined with 0.1 mol/L citric acid (CA) was valid for Cu washing for three different soils with removal rate ranged from 68.8 ± 0.8% to 83.2 ± 1.1%. Oxidation pretreatment was necessary when DOM was in high concentration.
Acknowledgement
This study was supported by Shanghai Environmental Ecological Remediation Technology Co., LTD, belonging to Shanghai Environment of Shanghai Cheng Tou. Authors would like to appreciate the corporation in the whole investigation.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Supplementary material
Supplemental data for this article can be accessed online at https://doi.org/10.1080/15567036.2022.2146237.