
Nanoscale Zero-Valent Iron (nZVI) for Heavy Metal Wastewater Treatment: A Perspective
Shaolin Li, Lei Li, Weixian Zhang
Engineering ›› 2024, Vol. 36 ›› Issue (5) : 16-20.
Nanoscale Zero-Valent Iron (nZVI) for Heavy Metal Wastewater Treatment: A Perspective
Industries such as non-ferrous metal smelting discharge billions of gallons of highly toxic heavy metal wastewater (HMW) worldwide annually, posing a severe challenge to conventional wastewater treatment plants and harming the environment. HMW is traditionally treated via chemical precipitation using lime, caustic, or sulfide, but the effluents do not meet the increasingly stringent discharge standards. This issue has spurred an increase in research and the development of innovative treatment technologies, among which those using nanoparticles receive particular interest. Among such initiatives, treatment using nanoscale zero-valent iron (nZVI) is one of the best developed. While nZVI is already well known for its site-remediation use, this perspective highlights its application in HMW treatment with metal recovery. We demonstrate several advantages of nZVI in this wastewater application, including its multifunctionality in sequestrating a wide array of metal(loid)s (> 30 species); its capability to capture and enrich metal(loid)s at low concentrations (with a removal capacity reaching 500 mg·g−1 nZVI); and its operational convenience due to its unique hydrodynamics. All these advantages are attributable to nZVI’s diminutive nanoparticle size and/or its unique iron chemistry. We also present the first engineering practice of this application, which has treated millions of cubic meters of HMW and recovered tons of valuable metals (e.g., Cu and Au). It is concluded that nZVI is a potent reagent for treating HMW and that nZVI technology provides an eco-solution to this toxic waste.
Nanoscale zero-valent iron / Wastewater / Heavy metal / Resource recovery
[1] |
|
[2] |
|
[3] |
|
[4] |
|
[5] |
|
[6] |
|
[7] |
|
[8] |
|
[9] |
|
[10] |
|
[11] |
|
[12] |
|
[13] |
|
[14] |
|
[15] |
|
[16] |
|
[17] |
|
[18] |
|
[19] |
|
[20] |
|
[21] |
|
[22] |
|
[23] |
|
[24] |
|
[25] |
|
[26] |
|
[27] |
|
[28] |
National Bureau of Statistics of China.Environmental statistical data ( 2013). Beijing: China Statistics Press; 2013. Chinese.
|
[29] |
General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China; Ministry of Ecology and Environmental Protection of People's Republic of China. GB 18918-2002: Discharge standard of pollutants for municipal wastewater treatment plant. Chinese standard. Beijing: Standard Press of China; 2002. Chinese.
|
[30] |
Ecology and Environment Department of Hunan; Administration for Market Regulation of Hunan Province. DB 43/968-2021:Discharge standard of thallium pollutant for industry wastewater. Hunan provincial standards. Beijing: Standard Press of China; 2021. Chinese.
|
[31] |
Ministry of Environmental Protection of China. GB 8978-1996: Integrated wastewater discharge standard. Chinese standard. Beijing: Standard Press of China; 1996. Chinese.
|
[32] |
Shanghai Municipal Bureau of Ecology and Environment; Shanghai Municipal Bureau of Quality and Technical Supervision. DB 31/199-2018:Integrated wastewater discharge standard. Shanghai provincial standards. Beijing: Standard Press of China; 2018. Chinese.
|
[33] |
|
[34] |
|
[35] |
|
[36] |
|
[37] |
|
[38] |
|
[39] |
|
[40] |
|
[41] |
|
[42] |
|
[43] |
|
[44] |
|
[45] |
|
[46] |
|
[47] |
|
[48] |
|
[49] |
|
[50] |
|
[51] |
|
[52] |
|
[53] |
|
This work was financially supported by the National Natural Science Foundation of China (21876131), the National Key Research and Development Program of China (2022YFC3702101), and the Foundation of State Key Laboratory of Pollution Control and Resource Reuse of China (PCRRY).
/
〈 |
|
〉 |