有机酸对污染土壤中铜和镉的浸提效果

Cu and Cd Extraction from Contaminated Soils by Organic Ligands

以采自湖北省大冶矿区长乐山的4种土壤为供试材料,研究了柠檬酸、酒石酸和EDTA在不同浓度、浸提时间和加入电解质等因素影响下对土壤中铜和镉的浸提效果。结果表明,有机酸对土壤中铜和镉的浸提量随有机酸浓度的增加而增加,但增幅与有机酸的种类有关。土壤中铜浸提30min,镉浸提1h可接近平衡。在柠檬酸处理中,加入电解质对铜和镉的浸提起抑制作用。

Chelation-induced phytoremediation technology which can enhance plants to absorb heavy metals is paid more attention. It is significant to apply this technique on remediation of heavy metals in contaminated soil. Four soils from the mining area of Daye, Hubei province were collected to investigate the extraction effect of three organic ligands （citric acid, tartaric acid and EDTA） on copper and cadmium from these soils, based on the conditions of different concentrations, extraction time and electrolyte addition. The results showed that the extraction amount of copper and cadmium related to the types and concentrations of the organic ligands and increased with the increasing concentration of the organic ligands. The extraction reached equilibrium for Cu in 30 min and for Cd in 1 hour. The addition of electrolyte to the citric acid treatment in the soils could decrease the amounts of extracted Cu and Cd.