Sustainable and reagent-free cathodic precipitation for high-efficiency removal of heavy metals from soil leachate*

被引:18
作者
Yang, Xiong [1 ,2 ]
Liu, Lihu [2 ]
Wang, Yi [2 ]
Lu, Tao [2 ]
Wang, Ziwei [2 ]
Qiu, Guohong [2 ,3 ]
机构
[1] Hubei Univ Technol, Sch Civil & Environm Engn, Wuhan 430068, Hubei, Peoples R China
[2] Huazhong Agr Univ, Interdisciplinary Sci Inst, Coll Resources & Environm, Hubei Key Lab Soil Environm & Pollut Remediat,Key, Wuhan 430070, Hubei, Peoples R China
[3] Chinese Acad Agr Sci, Agr Genom Inst Shenzhen, Shenzhen Branch, Guangdong Lab Lingnan Modern Agr,Genome Anal Lab,M, Shenzhen, Peoples R China
基金
中国国家自然科学基金;
关键词
Soil remediation; Washing; Leachate; Heavy metals; Cathodic precipitation; OXIDATION; IRON; ADSORPTION; MECHANISM; CHLORINE; ELECTRODEPOSITION; COPRECIPITATION; RECOVERY; OXALATE; FILMS;
D O I
10.1016/j.envpol.2023.121002
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Heavy metal pollution of soils has become a serious environmental problem. Soil washing with degradable reagents is an effective remediation technique of heavy metal pollution, and the generated leachate must be appropriately treated before discharge. However, the existing methods usually have the problems of large consumption of regents, high cost, and secondary pollution. This study proposed a reagent-free electrochemical precipitation method to remove mixed heavy metal ions extracted from soils by citrate using inert electrodes (IrO2-Ta2O5/Ti anode and graphite cathode). The results showed that the low potential of cathode led to the electrodeposition of Cd; the local alkaline environment provided by electro-mediated water reduction caused the hydrolytic precipitation of Zn and Pb; and the precipitation of Fe washed out from Fe-rich soil resulted in the coprecipitation of As on cathode surface. These combined cathodic precipitation processes decreased the concentrations of toxic heavy metals by over 99.4% after 12 h of electrolysis at 26 mA cm-2. The electrodes exhibited high stability after multiple successive cycles of reuse. The concentrations of As, Zn, Pb and Cd in the leachate decreased to below the limits of industrial wastewater discharge in each cycle, and those in soils could be reduced by 53.8%, 58.8%, 25.5%, and 70.2% at the initial concentrations of 1549, 1016, 310 and 50 mg kg-1, respectively. The heavy metal removal rate increased with increasing current density in the range of 0-52 mA cm-2. This work provides an efficient and sustainable method for the remediation of site soils polluted by mixed heavy metals.
引用
收藏
页数:9
相关论文
共 56 条
[41]   Degradation of pollutants in polluted river water using Ti/IrO2-Ta2O5 coating electrode and evaluation of electrode characteristics [J].
Wang, Hao ;
Wang, Jia ;
Bo, Guozhu ;
Wu, Shuangrong ;
Luo, Litiao .
JOURNAL OF CLEANER PRODUCTION, 2020, 273
[42]   Removal of As(V) from wastewaters using magnetic iron oxides formed by zero-valent iron electrocoagulation [J].
Wang, Yi ;
Liu, Lihu ;
Yang, Xiong ;
Suib, Steven L. ;
Qiu, Guohong .
JOURNAL OF ENVIRONMENTAL MANAGEMENT, 2022, 307
[43]   Arsenic fractionation in soils using an improved sequential extraction procedure [J].
Wenzel, WW ;
Kirchbaumer, N ;
Prohaska, T ;
Stingeder, G ;
Lombi, E ;
Adriano, DC .
ANALYTICA CHIMICA ACTA, 2001, 436 (02) :309-323
[44]   Carbonate adsorption mechanism on goethite studied with ATR-FTIR, DRIFT, and proton coadsorption measurements [J].
Wijnja, H ;
Schulthess, CP .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 2001, 65 (02) :324-330
[45]   Enhanced electrokinetic remediation for Cd-contaminated clay soil by addition of nitric acid, acetic acid, and EDTA: Effects on soil micro-ecology [J].
Xu, Haiyin ;
Zhao, Peiling ;
Ran, Qiyang ;
Li, Wenjuan ;
Wang, Ping ;
Luo, Yuanling ;
Huang, Chao ;
Yang, Xiong ;
Yin, Jingxuan ;
Zhang, Ruiqi .
SCIENCE OF THE TOTAL ENVIRONMENT, 2021, 772
[46]   Remediation of heavy metal contaminated soil by asymmetrical alternating current electrochemistry [J].
Xu, Jinwei ;
Liu, Chong ;
Hsu, Po-Chun ;
Zhao, Jie ;
Wu, Tong ;
Tang, Jing ;
Liu, Kai ;
Cui, Yi .
NATURE COMMUNICATIONS, 2019, 10 (1)
[47]   Structure and morphology of electrodeposited CaCO3:: X-ray diffraction and microscopy studies [J].
Xu, S ;
Melendres, CA ;
Park, JH ;
Kamrath, MA .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1999, 146 (09) :3315-3323
[48]   A critical review on chemical analysis of heavy metal complexes in water/wastewater and the mechanism of treatment methods [J].
Xu, Zhe ;
Zhang, Qingrui ;
Li, Xuchun ;
Huang, Xianfeng .
CHEMICAL ENGINEERING JOURNAL, 2022, 429
[49]   Electrochemical recovery and high value-added reutilization of heavy metal ions from wastewater: Recent advances and future trends [J].
Yang, Liming ;
Hu, Wenbin ;
Chang, Ziwen ;
Liu, Tian ;
Fang, Difan ;
Shao, Penghui ;
Shi, Hui ;
Luo, Xubiao .
ENVIRONMENT INTERNATIONAL, 2021, 152
[50]   Remediation of As-contaminated soils using citrate extraction coupled with electrochemical removal [J].
Yang, Xiong ;
Liu, Lihu ;
Wang, Yi ;
Qiu, Guohong .
SCIENCE OF THE TOTAL ENVIRONMENT, 2022, 817