EDTA和柠檬酸对污染土壤中Cd、Ni活化的影响

Effect of EDTA and citric acid on activation of cadium and nickel in Cd-Ni contaminated soil

以新乡市蓄电池厂周围的Cd、Ni污染土壤为研究对象,研究了不同浓度的EDTA、柠檬酸对Cd、Ni活化的影响。结果表明:在供试污染土壤中,Cd、Ni的活化量随着EDTA、柠檬酸浓度的增大而增大,EDTA对Cd、Ni的活化效果大于柠檬酸。在浓度为10.0mmol/L时,EDTA和柠檬酸对Cd、Ni的活化量都达到最大。EDTA和柠檬酸对Cd、Ni活化速度特性不同,EDTA对土壤Cd的活化速率大于柠檬酸,EDTA对土壤Ni的活化速率略大于柠檬酸。供试污染土壤中Ni不易被活化。

The city of Xinxiang is the base of battery production in our country; There are many heavy metals such as cadmium,nickel and so on in the battery production process. They can pollute the soil .We realized that there were serious heavy metal pollution situation in Xinxiang through the preparation test. Therefore,we decide to study how to remediate Cd-Ni compound contaminated soils .Taking the Cd-Ni contaminated farmlands in Xinxiang as research object,An experiment was conducted to investigate the influence of EDTA,citric acid on the activation of Cd and Ni in Cd-Ni contaminated soil. The results showed that the releasing amounts of Cd and Ni increased with the increase of EDTA or citric acid concentration. EDTA was more effective on the activation of Cd,and Ni than citric acid . EDTA or citric acid treated with 10.0 mmol·L^-1 had the highest release capacity,Ni was not easy to activate. The results indicated that,when we remediate Cd-Ni compound contaminated soils,the best repairing efficiency was observed in the treatment of applying 5.0 mmol·L^-1 or 10.0 mmol·L^-1 citric acid.