沸石-鸟粪石复合材料对土壤中铅的稳定化作用

Stabilization of Pb in contaminated soil using zeolite-struvite composites

从模拟污水中回收制备了一种沸石-鸟粪石复合材料(Zeo-str材料)并用于土壤中铅的稳定。通过SEM/EDS和XRD表征、重金属有效态提取,改进的BCR连续提取法和酶活性分析等手段,探讨了该材料对土壤中铅的稳定化效果。结果表明:Zeo-str材料的主要组成为鸟粪石负载的铵饱和沸石,且相比于沸石具有更好的铅稳定化能力;当施加10%的Zeo-str材料,稳定28 d后,土壤中铅的可交换态含量降低了83%,可还原态和残渣态含量分别上升了8.7倍和2.5倍,并使得被铅抑制的蔗糖酶活性上升,被铅激活的过氧化氢酶活性下降。由此可见,Zeo-str材料可以稳定土壤中的铅,进而实现废物的资源化利用。

Azeolite-struvite composites（Zeo-str material）was recovered in simulated wastewater and applied to stabilize Pb in soil. The stabilization effect of it was explored by SEM/EDS and XRD characterization, extraction of the available heavy metal, modified BCR sequential extraction procedures, enzymatic activity analysis, etc. The results showed that Zeo-str material mostly was the struvite loaded ammonium saturated zeolite and it performed better ability of stabilizing Pb than zeolite. After applying Zeo-str material into Pb contaminated soil at the dosage of 10% in 28 days, the fraction of exchangeable Pb decreased 83% while reducible Pb and residual Pb fractions increased 8.7 and2.5 times respectively, and sucrose enzyme activity increased while catalase activity decreased due to the stabilization of Pb in soil. In conclusion,Pb in soil can be stabilized by Zeo-str material, thus achieving resource utilization of waste.