柠檬酸对电动修复铬镍复合污染土壤的影响

摘要

通过分析不同电动修复时间对土壤的电流、pH、电导率及铬镍去除率的影响确定最佳电动修复时间为5 d.再通过正交解吸实验,考察阴极控制液和控制液浓度对电动修复铬镍复合污染土壤的影响.结果表明柠檬酸是EDTA、柠檬酸、酒石酸、乙酸四种常见阴极控制液中的最佳控制液,其最佳浓度为0.1 mol/L.在最佳的修复实验条件下铬的去除率可以达到61.76%,但是镍的修复率只有16.29%,这可能是由于加了阴极控制液后最佳修复时间应该适当延长.%The effects of electro-kinetic remediation time on soil current, pH, electrical conductivity and Cr-Ni removal rate were studied to determine the optimal treated time.Orthogonal desorption experiments are then conducted to study the effect of cathode liquid and the concentration on electro-kinetic remediation of chromium-nickel combined contaminated soil.The results showed that, among four types of cathode liquid including EDTA, citric acid, tartaric acid and acetic acid, citric acid is the most effective cathode liquid with 0.1 mol/L of optimal concentration.Under the optimum experimental conditions, the removal rate of chromium can reach 61.76%, but the rate of nickel is only 16.29%.This may be due to the fact the optimum treated time should be extended after the addition of citric acid used as cathode liquid.