Treatment of landfill leachate using magnetically attracted zero-valent iron powder electrode in an electric field

JOURNAL OF HAZARDOUS MATERIALS

卷:388

Article

Sun, Dongni^1,2  Hong, Xiaoting¹  Cui, Zhonghua³  Du, Yingying¹  Hui, K. S.⁴  Zhu, Enhao¹  Wu, Keming²  Hui, K. N.⁵ 

[1] Zhejiang Sci Tech Univ, Dept Chem, Hangzhou 310018, Peoples R China

[2] Wuhan Univ Sci & Technol, State Environm Protect Key Lab Mineral Met Resour, Wuhan 430081, Peoples R China

[3] Zhejiang Univ Sci & Technol, Sch Environm & Nat Resources, Hangzhou 310023, Peoples R China

[4] Univ East Anglia, Fac Sci, Sch Engn, Norwich NR4 7TJ, Norfolk, England

[5] Univ Macau, Inst Appl Phys & Mat Engn, Ave Univ, Taipa, Macao, Peoples R China

关键词: Landfill leachate;    Electro-oxidation;    Electrocoagulation;    Zero-valent iron;   

DOI  :  10.1016/j.jhazmat.2019.121768

来源: Elsevier

【 摘 要 】

This study combined electro-oxidation (EO) and electrocoagulation (EC) process (EO/EC) to treat landfill leachate by using RuO2-IrO2/Ti plate and microscale zero-valent iron powder composite anode. EO was achieved by direct oxidation and indirect oxidation on RuO2-IrO2/Ti plate, whereas EC was achieved using iron powder to lose electrons and produce coagulants in situ. The influences of variables including type of anode material, applied voltage, zero-valent iron dosage, interelectrode gap, and reaction temperature on EO/EC were evaluated. Results showed that at an applied voltage of 10 V, zero-valent iron dosage of 0.2 g, interelectrode gap of 1 cm, and non-temperature-controlled mode, the removal efficiencies were 72.5 % for total organic carbon (TOC), 98.5 % for ammonia, and 98.6 % for total phosphorus (TP). Some heavy metals and hardness were also removed. Further analysis indicated that the removal of TOC, ammonia, and TP followed pseudo-first order, pseudo-zero order, and pseudo-second order kinetic models, respectively. Other characteristics were examined by scanning electron microscopy-energy dispersive spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy. Overall, our results showed that EO/EC can be used to efficiently remove organic matter, ammonia, TP, and heavy metals from landfill leachate.

【 授权许可】

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