镉污染土壤钝化修复机制及研究进展

农田重金属钝化技术通过向污染土壤中添加一些活性物质,以降低重金属在土壤中的活性及生物有效性。该法不改变土壤固有的理化性状,是目前中轻度污染土壤修复较好的选择。综述了农田镉(Cd)污染常见的钝化剂种类、钝化效果及作用机制。Cd污染钝化修复剂的作用机制尚不完全清楚,其可能的机制为提供碱性环境,促进游离的Cd离子与土壤中阴离子形成一系列沉淀络合反应。钝化修复技术的优越性和局限性需要去合理控制,从而更好的治理改善Cd污染农田,为粮食安全提供保证。

Mechanism and Research Progress of Passivation Remediation of Cadmium Contaminated Soil

The heavy metal passivation technology in farmland has been apploed by adding some active substances to the contaminated soil, in order to reduce the activity and biological effectiveness of heavy metals in the soil. The method does not change the intrinsic physical and chemical properties of the soil, it is currently the better choice for remediation of mildly contaminated soil. This paper summarizes the types of passivator, passivation effect and working mechanism of passivator in common contamination. The working mechanism of Cd contamination passivator is not completely clear, and its possible mechanism is to provide alkaline environment, promoting the formation of a series of precipitation and complexation reactions between free Cd ions and anions in the soil. The advantages and limitations of passivation remediation technology need to be reasonably controlled, thus better governance to improve the Cd contamination farmland, to provide a guarantee for food security.