School of Environmental and Materials Engineering, Shanghai Polytechnic University, Shanghai, 201209, China.
Shanghai Collaborative Innovation Centre for WEEE Recycling, Shanghai Polytechnic University, Shanghai, 201209, China.
Chemosphere. 2021 Sep;279:130568. doi: 10.1016/j.chemosphere.2021.130568. Epub 2021 Apr 20.
Lead-contaminated soil was cleaned through ethylene-diamine-teraacetic acid disodium salt (EDTA-2Na) combined with diluted deep eutectic solvent (DES) which was prepared by mixing choline chloride with ethylene glycol. The influences of leaching temperature, leaching time, liquid-solid (L/S) ratio, concentration of EDTA-2Na, water-DES ratio, and the molar ratio of choline chloride-ethylene glycol (Ch-E) on the leaching rate of lead were investigated. The mineral phases of the soil and DES before and after washing were analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The changes to the DESs before and after dissolving lead nitrate (Pb(NO)) were analyzed by high resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR). Hydrogen bonds and EDTA-2Na in the Ch-M system resulted in the conversion of Pb(NO) to other complex ions such as [Pb·Ch-E] and [Pb·EDTA-2Na] and other complex ions due to the dissolution of the washing agent. The results showed that the soil mineral phase did not change significantly and up to 95.79% of Pb could be washed under temperature, time, L/S ratio, EDTA-2Na concentration, DES/water ratio, Ch-E molar ratio, and stirring speed conditions of 40 °C, 2 h, 6, 0.02 M, 2, 0.75 and 300 rpm, respectively. The hydrogen bonds and EDTA-2Na may play a key role in the remediation of lead-contaminated soil by a washing agent. This research describes a rapid, efficient, and environmentally friendly method for remediation of lead-contaminated soil.
采用乙二胺四乙酸二钠（EDTA-2Na）与稀释的深共晶溶剂（DES）联合对含铅污染土壤进行修复，DES 由氯化胆碱与乙二醇混合制成。考察了浸出温度、浸出时间、液固比（L/S）、EDTA-2Na 浓度、水-DES 比、氯化胆碱-乙二醇摩尔比（Ch-E）对铅浸出率的影响。采用扫描电子显微镜（SEM）、X 射线衍射（XRD）和傅里叶变换红外光谱（FT-IR）对洗涤前后土壤和 DES 的矿物相进行了分析。采用高分辨质谱（HRMS）和核磁共振（NMR）分析了溶解硝酸铅（Pb(NO))前后 DES 的变化。Ch-M 体系中的氢键和 EDTA-2Na 导致 Pb(NO)转化为其他络合离子，如[Pb·Ch-E]和[Pb·EDTA-2Na]等络合离子，这是由于洗涤剂的溶解所致。结果表明，在 40°C、2 h、6、0.02 M、2、0.75 和 300 rpm 的温度、时间、L/S 比、EDTA-2Na 浓度、DES/水比、Ch-E 摩尔比和搅拌速度条件下，土壤矿物相变化不大，铅去除率高达 95.79%。氢键和 EDTA-2Na 可能在洗涤剂修复铅污染土壤中起关键作用。本研究描述了一种快速、高效、环保的修复铅污染土壤的方法。
