College of Environmental Sciences, Sichuan Agricultural University, Wenjiang, 611130, China.
College of Environmental Sciences, Sichuan Agricultural University, Wenjiang, 611130, China.
J Hazard Mater. 2017 Oct 5;339:33-42. doi: 10.1016/j.jhazmat.2017.06.007. Epub 2017 Jun 10.
Plant washing agents-water-extracted from Coriaria nepalensis (CN), Clematis brevicaudata (CB), Pistacia weinmannifolia (PW) and Ricinus communis (RC)-are feasible and eco-friendly for soil heavy metal removal, but their single application has limited removal efficiency. To improve their metal removal efficiencies, two biodegradable assistant agents, hydrolytic polymaleic anhydride (HPMA) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), were investigated in combination with plant washing agents through batch soil washing experiments. Results showed that the addition of HPMA or PBTCA with plant agents greatly enhanced the removal efficiencies of soil heavy metals (p<0.05). Under acidic conditions, the maximum improvements in soil heavy metal removal reached 18.69% and 18.00% for soil Cd and Zn by PW+HPMA, respectively, and 12.89% for soil Pb by CN+HPMA. Under neutral or alkaline conditions, the largest improvements in soil Cd, Pb and Zn were 24.18%, 54.38% and 25.47% by PW+PBTCA, respectively. When compared with EDTA, the loss rates of soil nitrogen, phosphorus and potassium significantly decreased (p<0.05) and the soil organic carbon significantly increased (p<0.05) after washing with the combinations. Hence, the addition of HPMA or PBTCA with the plant agents could improve the removal of soil heavy metals.
植物洗脱剂-从尼泊尔桑寄生（CN）、短尾铁线莲（CB）、黄连木（PW）和蓖麻（RC）中提取的水-是去除土壤重金属的可行且环保的方法，但它们的单一应用去除效率有限。为了提高它们的金属去除效率，两种可生物降解的助剂-水解聚马来酸（HPMA）和 2-膦丁烷-1,2,4-三羧酸（PBTCA）-与植物洗脱剂一起通过批量土壤洗脱实验进行了研究。结果表明，HPMA 或 PBTCA 与植物洗脱剂的添加大大提高了土壤重金属的去除效率（p<0.05）。在酸性条件下，PW+HPMA 对土壤 Cd 和 Zn 的去除率最大提高了 18.69%和 18.00%，CN+HPMA 对土壤 Pb 的去除率最大提高了 12.89%。在中性或碱性条件下，PW+PBTCA 对土壤 Cd、Pb 和 Zn 的去除率最大提高了 24.18%、54.38%和 25.47%。与 EDTA 相比，组合洗脱后土壤氮、磷和钾的损失率显著降低（p<0.05），土壤有机碳显著增加（p<0.05）。因此，HPMA 或 PBTCA 与植物洗脱剂的添加可以提高土壤重金属的去除率。
