摘要
以凹凸棒土为原材料进行了热改性、酸改性、壳聚糖负载改性,并采用SEM、FT-IR、XRD表征其结构变化。通过改性凹凸棒土对土壤Cd~(2+)吸附解吸及土柱淋溶实验表明:凹凸棒土及改性凹凸棒土均能有效提高土壤对Cd~(2+)的吸附容量,减少Cd~(2+)的纵向迁移,降低淋溶风险。改性凹凸棒土主要是通过降低土壤中Cd的交换态和碳酸结合态含量增加土壤中Cd的铁锰氧化结合态及有机态含量,达到钝化土壤中Cd效果,综合处理效果优劣顺序为热改性凹凸棒土>酸改性凹凸棒>凹凸棒土>壳聚糖改性凹凸棒土>空白。
Thermal modification,acid modification and chitosan loading modification were performed using attapulgite as a raw material. The structure was characterized by SEM,FT-IR and XRD. Adsorption and desorption of soil and soil column leaching experiments by modified attapulgite showed that attapulgite and modified attapulgite could effectively increase the Cd~(2+)adsorption capacity of the soil,reduce the longitudinal migration of Cd~(2+)and risk of leaching. The modified attapulgite mainly increased the oxidized and organic iron-manganese content of Cd by reducing the exchangeable state and carbonation-bound content of Cd to immobilization Cd in soil. Comprehensive treatment showed that thermal modified attapulgite>acid modified attapulgite>attapulgite>chitosan loading modified attapulgite>Blank.
引文
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