新型ED3A类螯合性表面活性剂淋洗修复重金属污染土壤的研究

Leaching Remediation of Heavy Metal Contaminated Soil with a Novel Ethylenediamine Triacetate Chelating Surfactant

研究了新型乙二胺三乙酸盐(ED3A)类螯合性表面活性剂N-(3-十二烷氧基-2-羟基丙基)乙二胺三乙酸钠(C12-ED3A3Na)淋洗修复重金属污染农田土壤的淋洗效果。结果表明,C12-ED3A3Na在浓度为0.05 mol/L,pH值为11.48,淋洗时间为8 h时,可达到最佳淋洗效果;在最佳淋洗条件下C12-ED3A3Na溶液对土壤中Pb、Cu和Zn的去除率分别达到37.12%、32.60%和19.77%;C12-ED3A3Na不仅能有效去除土壤中可交换态、碳酸盐结合态和铁锰氧化态的Pb、Cu和Zn,对有机态的和残渣态的Pb、Cu和Zn也有一定去除作用。

The leaching effect of heavy metal contaminated farmland soil by a novel ethylenediamine triace-tate (ED3A) chelating surfactant sodium N-(3-dodecyloxy-2-hydroxypropyl) ethylenediamine tri-acetate (C12-ED3A3Na) was investigated. The results showed that C12-ED3A3Na solution could obtain the optimal heavy metal removal effect when its concentration was 0.1 mol/L, its pH was 11.48, the leaching time was 8 h, and the leaching temperature was 35?C. Under these leaching conditions, its removal efficiency was 37.12% for Pb, 32.60% for Cu and 19.77% for Zn, respectively. The chelating surfactant could effectively remove the metals in the exchangeable, carbonates-bound and Fe/Mn oxides of low crystallinity fractions in the soil, and also had a certain metal removal effect on their organic-bound and residual fractions.