title: Decontamination of electronic waste-polluted soil by ultrasound-assisted soil washing.
abstract: Laboratorial scale experiments were performed to evaluate the efficacy of a washing process using the combination of methyl-β-cyclodextrin (MCD) and tea saponin (TS) for simultaneous desorption of hydrophobic organic contaminants (HOCs) and heavy metals from an electronic waste (e-waste) site. Ultrasonically aided mixing of the field contaminated soil with a combination of MCD and TS solutions simultaneously mobilizes most of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and the analyte metal (Pb, Cu, and Ni) burdens. It is found that 15 g/L MCD and 10 g/L TS is an efficient reagent combination reconciling extraction performance and reagent costs. Under these conditions, the removal efficiencies of HOCs and heavy metals are 93.5 and 91.2 %, respectively, after 2 cycles of 60-min ultrasound-assisted washing cycles. By contrast, 86.3 % of HOCs and 88.4 % of metals are removed from the soil in the absence of ultrasound after 3 cycles of 120-min washing. The ultrasound-assisted soil washing could generate high removal efficiency and decrease the operating time significantly. Finally, the feasibility of regenerating and reusing the spent washing solution in extracting pollutants from the soil is also demonstrated. By application of this integrated technology, it is possible to recycle the washing solution for a purpose to reduce the consumption of surfactant solutions. Collectively, it has provided an effective and economic treatment of e-waste-polluted soil.
authors.affiliation: Low Carbon Energy Institute, China University of Mining and Technology, Xuzhou, 221008, People's Republic of China. chenfucunt@163.com.|School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, 221043, People's Republic of China. chenfucunt@163.com.|School of Mathematical and Geospatial Sciences, Royal Melbourne Institute of Technology University, Melbourne, 3000, Australia. chenfucunt@163.com.
authors.forename: Fu
authors.initials: F
authors.lastname: Chen
authors.affiliation: School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, 221043, People's Republic of China.
authors.forename: Baodan
authors.initials: B
authors.lastname: Yang
authors.affiliation: Low Carbon Energy Institute, China University of Mining and Technology, Xuzhou, 221008, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ma
authors.affiliation: Low Carbon Energy Institute, China University of Mining and Technology, Xuzhou, 221008, People's Republic of China.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Qu
authors.affiliation: School of Mathematical and Geospatial Sciences, Royal Melbourne Institute of Technology University, Melbourne, 3000, Australia.
authors.forename: Gangjun
authors.initials: G
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D059029:Electronic Waste / Q000009:adverse effects*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D019216:Metals, Heavy / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry; D012503:Saponins / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry; D014465:Ultrasonics / Q000379:methods*; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D012503:Saponins; D012987:Soil; D012989:Soil Pollutants; D013501:Surface-Active Agents; D047392:beta-Cyclodextrins; C108732:methyl-beta-cyclodextrin; D011078:Polychlorinated Biphenyls
keywords: Desorption; Soil washing; Tea saponin; Ultrasonication