Wei Chen, Peng Cui, Lian Zhou, Han Zheng, Xude Zhao, Guansheng Liu, Juntao Zhang, Hua Zhong
{"title":"In-situ activation of persulfate by emplaced magnetite nanoparticles for degradation of 1,2-dichloroethane in porous media","authors":"Wei Chen, Peng Cui, Lian Zhou, Han Zheng, Xude Zhao, Guansheng Liu, Juntao Zhang, Hua Zhong","doi":"10.1016/j.watres.2024.122574","DOIUrl":null,"url":null,"abstract":"In this study, column experiments were conducted to explore on the method of emplacement of magnetite nanoparticles (MNPs) for in situ activation of persulfate (PS) in sand porous media to degrade 1,2-dichloroethane (DCA), a typical recalcitrant chlorinated compound. Different molar ratios between PS and DCA (0:1, 2:1, 5:1 and 20:1) and mass contents of MNPs in the sand (0%, 1.9% and 5.4%) were tested. In the absence of MNPs, degradation of DCA was negligible for a hydraulic retention time of 7 h. Presence of MNPs at the content of 1.9% enhanced degradation of DCA and the highest removal efficiency (34.2%) was observed at the PS-to-DCA molar ratio of 5:1. At the MNPs content of 5.4%, increase of the PS-to-DCA molar ratio from 2:1 to 20:1 lead to not only increase in DCA removal efficiency but also substantial enhancement in chloride production, indicating that high PS concentration could cause significant degradation of the Cl-containing intermediates. In contrast to MNPs, Fe<sub>3</sub>O<sub>4</sub> solids with much larger size (∼1 μm) were much less effective in activating PS for DCA removal even at a significantly higher content in the medium. The transport data could be well fitted by the one-site chemical nonequilibrium model, which showed kinetic DCA sorption to the MNPs as a key process for the transport. In the long-term injection experiment, a stable and significant removal of DCA (∼50%) was observed for 254 days at the MNP content of 1.9 %. The results of this study show the potential of MNPs as a sustainable PS activator in injection-based in situ chemical oxidation for groundwater remediation.","PeriodicalId":443,"journal":{"name":"Water Research","volume":null,"pages":null},"PeriodicalIF":11.4000,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Water Research","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1016/j.watres.2024.122574","RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, ENVIRONMENTAL","Score":null,"Total":0}
引用次数: 0
Abstract
In this study, column experiments were conducted to explore on the method of emplacement of magnetite nanoparticles (MNPs) for in situ activation of persulfate (PS) in sand porous media to degrade 1,2-dichloroethane (DCA), a typical recalcitrant chlorinated compound. Different molar ratios between PS and DCA (0:1, 2:1, 5:1 and 20:1) and mass contents of MNPs in the sand (0%, 1.9% and 5.4%) were tested. In the absence of MNPs, degradation of DCA was negligible for a hydraulic retention time of 7 h. Presence of MNPs at the content of 1.9% enhanced degradation of DCA and the highest removal efficiency (34.2%) was observed at the PS-to-DCA molar ratio of 5:1. At the MNPs content of 5.4%, increase of the PS-to-DCA molar ratio from 2:1 to 20:1 lead to not only increase in DCA removal efficiency but also substantial enhancement in chloride production, indicating that high PS concentration could cause significant degradation of the Cl-containing intermediates. In contrast to MNPs, Fe3O4 solids with much larger size (∼1 μm) were much less effective in activating PS for DCA removal even at a significantly higher content in the medium. The transport data could be well fitted by the one-site chemical nonequilibrium model, which showed kinetic DCA sorption to the MNPs as a key process for the transport. In the long-term injection experiment, a stable and significant removal of DCA (∼50%) was observed for 254 days at the MNP content of 1.9 %. The results of this study show the potential of MNPs as a sustainable PS activator in injection-based in situ chemical oxidation for groundwater remediation.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.