Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea.
Department of Energy and Resource Engineering, Chosun University, Gwangju 61452, Korea.
Int J Environ Res Public Health. 2020 Apr 30;17(9):3133. doi: 10.3390/ijerph17093133.
In this study, we investigated the feasibility of using a solution of sulfuric acid and phosphoric acid as an extraction method for soil-washing to remove Cu, Pb, Zn, and As from contaminated soil. We treated various soil particles, including seven fraction sizes, using sulfuric acid. In addition, to improve Cu, Pb, Zn, and As removal efficiencies, washing agents were compared through batch experiments. The results showed that each agent behaved differently when reacting with heavy metals (Cu, Pb, and Zn) and As. Sulfuric acid was more effective in extracting heavy metals than in extracting As. However, phosphoric acid was not effective in extracting heavy metals. Compared with each inorganic acid, As removal from soil by washing agents increased in the order of sulfuric acid (35.81%) < phosphoric acid (62.96%). Therefore, an enhanced mixture solution using sulfuric acid and phosphoric acid to simultaneously remove heavy metals and As from contaminated soils was investigated. Sulfuric acid at 0.6 M was adopted to combine with 0.6 M phosphoric acid to obtain the mixture solution (1:1) that was used to determine the effect for the simultaneous removal of both heavy metals and As from the contaminated soil. The removal efficiencies of As, Cu, Pb, and Zn were 70.5%, 79.6%, 80.1%, and 71.2%, respectively. The combination of sulfuric acid with phosphoric acid increased the overall As and heavy metal extraction efficiencies from the contaminated soil samples. With the combined effect of dissolving oxides and ion exchange under combined washings, the removal efficiencies of heavy metals and As were higher than those of single washings.
在本研究中，我们考察了采用硫酸和磷酸混合溶液作为淋洗剂从污染土壤中提取 Cu、Pb、Zn 和 As 的可行性。我们用硫酸处理了包括 7 种不同粒径的土壤颗粒。此外，为了提高 Cu、Pb、Zn 和 As 的去除效率，我们通过批实验对淋洗剂进行了比较。结果表明，每种淋洗剂与重金属（Cu、Pb 和 Zn）和 As 反应时表现出不同的行为。硫酸在提取重金属方面比提取 As 更有效。然而，磷酸在提取重金属方面效果不佳。与每种无机酸相比，通过淋洗剂从土壤中去除 As 的顺序为硫酸（35.81%）<磷酸（62.96%）。因此，研究了一种采用硫酸和磷酸的增强混合溶液同时从污染土壤中去除重金属和 As。采用 0.6 M 硫酸与 0.6 M 磷酸混合得到混合溶液（1:1），并用于确定该混合溶液同时从污染土壤中去除重金属和 As 的效果。As、Cu、Pb 和 Zn 的去除率分别为 70.5%、79.6%、80.1%和 71.2%。硫酸与磷酸的组合提高了从污染土壤样品中提取 As 和重金属的总体效率。通过联合淋洗下氧化物溶解和离子交换的共同作用，重金属和 As 的去除率高于单一淋洗。
