Department of Environmental Engineering, Chosun University, Gwangju, 501-759, Republic of Korea,
Environ Sci Pollut Res Int. 2013 Dec;20(12):8464-71. doi: 10.1007/s11356-013-1964-7. Epub 2013 Jul 16.
Soybean stover-derived biochar was used to immobilize lead (Pb) in military firing range soil at a mass application rate of 0 to 20 wt.% and a curing period of 7 days. The toxicity characteristic leaching procedure (TCLP) was performed to evaluate the effectiveness of the treatment. The mechanism responsible for Pb immobilization in military firing range soil was evaluated by scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray absorption fine structure (XAFS) spectroscopy analyses. The treatment results showed that TCLP Pb leachability decreased with increasing biochar content. A reduction of over 90 % in Pb leachability was achieved upon treatment with 20 wt.% soybean stover-derived biochar. SEM-EDX, elemental dot mapping and XAFS results in conjunction with TCLP leachability revealed that effective Pb immobilization was probably associated with the pozzolanic reaction products, chloropyromorphite and Pb-phosphate. The results of this study demonstrated that soybean stover-derived biochar was effective in immobilizing Pb in contaminated firing range soil.
将大豆秸秆衍生生物炭以 0 至 20wt.%的质量添加量和 7 天的养护期应用于军事射击场土壤中，以固定其中的铅 (Pb)。采用毒性特征浸出程序 (TCLP) 来评估处理效果。通过扫描电子显微镜-能量色散 X 射线光谱 (SEM-EDX) 和 X 射线吸收精细结构 (XAFS) 光谱分析评估了军事射击场土壤中 Pb 固定的机理。处理结果表明，随着生物炭含量的增加，TCLP 中 Pb 的浸出率降低。添加 20wt.%大豆秸秆衍生生物炭后，Pb 的浸出率降低了 90%以上。SEM-EDX、元素点映射和 XAFS 结果与 TCLP 浸出率相结合表明，有效的 Pb 固定可能与火山灰反应产物、氯磷铅矿和 Pb-磷酸盐有关。本研究结果表明，大豆秸秆衍生生物炭可有效固定污染射击场土壤中的 Pb。
