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Chakraborty P, Krishnani KK, Mulchandani A, Paniprasad K, Sarkar DJ, Sawant PB, Kumar N, Sarkar B, Mallik A, Pal P, Nagendrasai K, Das BK. Speciation-specific chromium bioaccumulation and detoxification in fish using hydrogel microencapsulated biogenic nanosilver and zeolite synergizing with biomarkers. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2024; 46:298. [PMID: 38980518 DOI: 10.1007/s10653-024-02061-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 05/31/2024] [Indexed: 07/10/2024]
Abstract
Grass carp intestinal waste-mediated biosynthesized nanosilver (AgNPs) was valorized using guaran and zeolite matrices, resulting in AgNPs-guaran, AgNPs-zeolite, and AgNPs-guaran -zeolite composites. The valorized products were examined using Environmental Scanning Electron Microscopy, Energy Dispersive X-ray analysis and X-ray Diffraction analysis to confirm uniform dispersion and entrapment of AgNPs within the matrixes. These valorized products were evaluated for their efficacy in detoxifying the ubiquitous and toxic hexavalent chromium (Cr6+) in aquatic environments, with Anabas testudineus exposed to 2 mg l-1 of Cr6+ for 60 days. Remarkable reduction of Cr6+ concentration to 0.86 ± 0.007 mg l-1 was achieved with AgNPs-guaran-zeolite composite, indicating successful reclamation of contaminated water and food safety assurance. Consistency in results was further corroborated by minimal stress-related alterations in fish physiological parameters and integrated biomarker response within the experimental group treated with the AgNPs-guaran-zeolite composite. Despite observed chromium accumulation in fish tissues, evidence of physiological stability was apparent, potentially attributable to trivalent chromium accumulation, serving as an essential nutrient for the fish. Additionally, the challenge study involving Anabas testudineus exposed to Aeromonas hydrophila exhibited the lowest cumulative mortality (11.11%) and highest survival rate (87.5%) within the same experimental group. The current study presents a novel approach encompassing the valorization of AgNPs for Cr6+ detoxification under neutral to alkaline pH conditions, offering a comprehensive framework for environmental remediation.
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Affiliation(s)
- Puja Chakraborty
- ICAR-Central Institute of Fisheries Education, Panch Marg, Off Yari Road, Versova, Andheri (W), Mumbai, 400061, India
| | - Kishore Kumar Krishnani
- ICAR-Central Institute of Fisheries Education, Panch Marg, Off Yari Road, Versova, Andheri (W), Mumbai, 400061, India.
- ICAR-Indian Institute of Agricultural Biotechnology, Ranchi, Jharkhand, 834010, India.
| | - Ashok Mulchandani
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA
| | - Kurcheti Paniprasad
- ICAR-Central Institute of Fisheries Education, Panch Marg, Off Yari Road, Versova, Andheri (W), Mumbai, 400061, India
| | - Dhruba Jyoti Sarkar
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, 700120, Kolkata, India
| | - Paramita Banerjee Sawant
- ICAR-Central Institute of Fisheries Education, Panch Marg, Off Yari Road, Versova, Andheri (W), Mumbai, 400061, India
| | - Neeraj Kumar
- ICAR-National Institute of Abiotic Stress Management, Baramati, Pune, Maharashtra, 413115, India
| | - Biplab Sarkar
- ICAR-Indian Institute of Agricultural Biotechnology, Ranchi, Jharkhand, 834010, India
| | - Abhijit Mallik
- ICAR-Central Institute of Fisheries Education, Panch Marg, Off Yari Road, Versova, Andheri (W), Mumbai, 400061, India
| | - Prasenjit Pal
- College of Fisheries, Central Agricultural University, Imphal, 799210, India
| | - Kurapati Nagendrasai
- ICAR-Central Institute of Fisheries Education, Panch Marg, Off Yari Road, Versova, Andheri (W), Mumbai, 400061, India
| | - Basanta Kumar Das
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, 700120, Kolkata, India
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Liu J, Sun S, Zhang H, Kong Q, Li Q, Yao X. Remediation materials for the immobilization of hexavalent chromium in contaminated soil: Preparation, applications, and mechanisms. ENVIRONMENTAL RESEARCH 2023; 237:116918. [PMID: 37611786 DOI: 10.1016/j.envres.2023.116918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 07/01/2023] [Accepted: 08/16/2023] [Indexed: 08/25/2023]
Abstract
Hexavalent chromium is a toxic metal that can induce severe chromium contamination of soil, posing a potential risk to human health and ecosystems. In recent years, the immobilization of Cr(VI) using remediation materials including inorganic materials, organic materials, microbial agents, and composites has exhibited great potential in remediating Cr(VI)-contaminated soil owing to the environmental-friendliness, short period, simple operation, low cost, applicability on an industrial scale, and high efficiency of these materials. Therefore, a systematical summary of the current progress on various remediation materials is essential. This work introduces the production (sources) of remediation materials and examines their characteristics in detail. Additionally, a critical summary of recent research on the utilization of remediation materials for the stabilization of Cr(VI) in the soil is provided, together with an evaluation of their remediation efficiencies toward Cr(VI). The influences of remediation material applications on soil physicochemical properties, microbial community structure, and plant growth are summarized. The immobilization mechanisms of remediation materials toward Cr(VI) in the soil are illuminated. Importantly, this study evaluates the feasibility of each remediation material application for Cr(VI) remediation. The latest knowledge on the development of remediation materials for the immobilization of Cr(VI) in the soil is also presented. Overall, this review will provide a reference for the development of remediation materials and their application in remediating Cr(VI)-contaminated soil.
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Affiliation(s)
- Jiwei Liu
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China.
| | - Shuyu Sun
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Huanxin Zhang
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Qiang Kong
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China; Dongying Institute, Shandong Normal University, Dongying, Shandong, 257092, China
| | - Qian Li
- School of Modern Agriculture and Environment, Weifang Institute of Technology, Weifang, Shandong, 261000, China
| | - Xudong Yao
- Project Department, Shandong Luqiao Detection Technology Co., Ltd., Rizhao, Shandong, 276800, China
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Zheng Y, Yu Q, Yu L, Zhang P, Zeng L, Lin X, Han R, Li D. Enhanced remediation of surface-bound hexavalent chromium in soils using the acidic and alkaline fronts of electrokinetic technology. CHEMOSPHERE 2022; 307:135905. [PMID: 35931266 DOI: 10.1016/j.chemosphere.2022.135905] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/28/2022] [Accepted: 07/30/2022] [Indexed: 06/15/2023]
Abstract
In the subsurface environment, highly toxic hexavalent chromium (Cr(VI)) control and remediation are essential to avoid further ecological impacts and reduce environmental risks. This paper investigated the enhanced Cr(VI) electrokinetic removal in the soil through the approaching cathode method. Besides, a novel four-step sequential fractionation method was used to reflect the strength of Cr(VI) binding to the soil. The approaching cathode enhanced the electrokinetic delivery of surface-bound Cr(VI) by advancing the alkaline front for Cr(VI) desorption and improving the electric potential flattening of the soil layers. Desorption of Cr(VI) by the alkaline front involved converting the inner-sphere complexes form of Cr(VI) to a weakly adsorbed form susceptible to ionic strength. In addition, the acidic front provided a favorable environment for the photochemical reduction of Cr(VI) by soil species or the added citrate as the electron donors. Improving the potential distribution could regulate the energy consumption of individual soil layers and efficiently operate the electrokinetic transfer of pollutants. The work results have significant scientific and practical significance for applying the in-situ electrokinetic technique in subsurface pollution control.
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Affiliation(s)
- Yi Zheng
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Qiu Yu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Lin Yu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Pengpeng Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Linghao Zeng
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Xiaosha Lin
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Renhui Han
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Dongwei Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing, 400044, China.
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Zheng Y, Yu L, Yan Y, Li H, Yu Q, Jiao B, Li D. Rapid Cr(VI) reduction structure in chromium contaminated soil: The UV-assisted electrokinetic circulation of background iron. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 822:153508. [PMID: 35101496 DOI: 10.1016/j.scitotenv.2022.153508] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 01/11/2022] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
Substantially decreasing the severe hazards connected with the toxic Cr(VI), developing effective reduction remediation strategies may be crucial under favorable economic conditions for the contaminated soil containing Cr(VI) to protect human health. Several typical enhancers (phosphate, fulvic acid, citric acid) were used to test electrokinetic remediation (EKR) coupled with UV radiation-induced photochemical reduction for contaminated soil containing Cr(VI). The added citrate, while improving the Cr(VI) electromigration, worked as the ultimate sacrificial electron donors, with the dissolved soil background Fe(III) as electron shuttle, to Cr(VI) rapid reduction. The dissolved soil background Fe(III) convert into Fe(II) ions through the UV radiation-induced ligand-metal charge transfers reaction, which constituted a novel electrokinetic circulation reduction pathway for the elimination of surface-bound/dissolved Cr(VI) (difficult to electromigration) in the near-anodic soil layers. More than 80% dissolved and surface-bound Cr(VI) was eliminated from the soil. In particular, the dissolved and surface-bound Cr(VI) was enhanced by more than 62.37% removal in near-anodic soil layers compared to conventional citric acid-enhanced EKR and provided no extra cost other than UV radiation. This configuration may be a cost-effective and feasible remediation design in the future for the in-situ Cr(VI) reduction of contaminated sites.
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Affiliation(s)
- Yi Zheng
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing 400044, China
| | - Lin Yu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing 400044, China
| | - Yujie Yan
- Engineering Research Center of Biofilm Water Purification and Utilization Technology, Ministry of Education, Anhui University of Technology, Maanshan, Anhui 243002, PR China
| | - Huilin Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing 400044, China
| | - Qiu Yu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing 400044, China
| | - Binquan Jiao
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing 400044, China
| | - Dongwei Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; College of Resource and Safety Engineering, Chongqing University, Chongqing 400044, China.
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Li D, Li G, He Y, Zhao Y, Miao Q, Zhang H, Yuan Y, Zhang D. Key Cr species controlling Cr stability in contaminated soils before and chemical stabilization at a remediation engineering site. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127532. [PMID: 34879522 DOI: 10.1016/j.jhazmat.2021.127532] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/06/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
Linking chromium (Cr) speciation with its stability in soils is vital because insoluble Cr(VI) and chemically adsorbed Cr(VI) could hinder the remediation efficiency and release Cr(VI) for a prolonged period of time. In this study, we investigated key Cr species to probe the mechanisms controlling the release of insoluble Cr(VI) at Cr-contaminated sites using synchrotron-based X-ray absorption near-edge structure (XANES) for the first time. Chromite, stichtite and Cr-silicate were predominant forms of Cr(III). Insoluble Cr(VI) was hosted by layered double hydroxides (LDHs) such as brownmilerite and hydrotalcite. Anion competition tests documented a substitution of absorbed Cr(VI) by SO42- and NO3-. Acid extraction released 6.7-25.7% more Cr(VI) than anion extraction, possibly attributing to the erosion of LDH and CaCrO4 in calcite rather than Cr-bearing minerals. Brown and red soils released maximally 62% and 44% of total Cr(VI) by 10 mol/(kg soil) and 2 mol/(kg soil) of H+, respectively. SO42-, H2O and H+ contributed to more release of total Cr(VI) in brown soils (22%, 33% and 7%) than red soils (25%, 17% and 2%). More crystalline Cr structures were found after chemical stabilization, indicating a higher Cr stability in chemically stabilized soils. Cr and Mn exhibited an overlapped distribution pattern in both contaminated and chemically stabilized soils, hinting at the re-oxidation of Cr(III). Insoluble Cr(VI) could be released by acidic rainfalls and soil organic matters, posing potential threats to Cr long-term stability in field-scale remediation.
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Affiliation(s)
- Danni Li
- School of Environment, Tsinghua University, Beijing 100084, PR China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, PR China
| | - Guanghe Li
- School of Environment, Tsinghua University, Beijing 100084, PR China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, PR China
| | - Yuning He
- Research Institute for Environmental Innovation (Tsinghua-Suzhou), Suzhou 215163, PR China
| | - Yingshuang Zhao
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Qiuci Miao
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hao Zhang
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Ying Yuan
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Dayi Zhang
- School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Tsinghua-Suzhou), Suzhou 215163, PR China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, PR China.
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Kajala R, Tomar SS, Verma N, Nigam KDP. Catalytic reduction of in-flow aqueous Cr( vi) using a slurry of activated carbon fiber-supported Ni nanoparticles in a coiled flow inverter. REACT CHEM ENG 2022. [DOI: 10.1039/d2re00226d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
CFI technology is utilized for the in-flow reduction of Cr(vi) using formic acid as the reducing agent and an aqueous dispersion of Ni/ACF, as an alternative to the conventional packed bed reactors.
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Affiliation(s)
- Rakshit Kajala
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Shivam Singh Tomar
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Nishith Verma
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
- Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - K. D. P. Nigam
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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Hu S, Li D, Man Y, Wen Y, Huang C. Evaluation of remediation of Cr(VI)-contaminated soils by calcium polysulfide: Long-term stabilization and mechanism studies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 790:148140. [PMID: 34102445 DOI: 10.1016/j.scitotenv.2021.148140] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/03/2021] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
In the remediation of Cr(VI)-contaminated soils, the effectiveness and long-term stability are critical qualities for the selection of a reductant. In current engineering practices, iron-based materials and sulfides are the most prevalent reductants, and calcium polysulfide (CaS4) is considered as the one with the highest effectiveness and strongest long-term stabilization ability. But this opinion is questioned by the high interference ability of CaS4 to soil Cr(VI) analysis. This study provides a pretreatment method to eliminate the interference of residual ferrous and sulfides to soil Cr(VI) analysis. By this pretreatment method and comparing with FeSO4 and Na2S, the mechanisms of the false high effectiveness and strong long-term stabilization ability of CaS4 is revealed. In the remediation process, CaS4 produces much elemental sulfur (S0) which remains in the soils. During the alkaline digestion, the S0 generates polysulfide which reduces the extracted Cr(VI), inducing serious negative analysis bias. When this negative bias is eliminated by pretreatment method, analysis results show that CaS4 exhibits lowest effectiveness. The S0 cannot be leached away from soils and oxidized by oxygen under natural conditions, this makes CaS4 exhibit a persistent interference ability, which is mistaken for a strong long-term stabilization ability.
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Affiliation(s)
- Siyang Hu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
| | - Dong Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, PR China; Key Laboratory of Southwest Resources Exploitation and Environmental Hazards Controlling Engineering of Education Ministry, Chongqing University, Chongqing 400044, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China.
| | - Yidong Man
- College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
| | - Yongyue Wen
- College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
| | - Chuan Huang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, PR China; Key Laboratory of Southwest Resources Exploitation and Environmental Hazards Controlling Engineering of Education Ministry, Chongqing University, Chongqing 400044, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
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Wang J, Liu X, Zhu Z, Yuan L, Zhao D, Deng H, Lin Z. Microwave-enhanced reductive immobilization of high concentrations of chromium in a field soil using iron polysulfide. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126293. [PMID: 34118547 DOI: 10.1016/j.jhazmat.2021.126293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/10/2021] [Accepted: 05/31/2021] [Indexed: 06/12/2023]
Abstract
High concentrations of Cr(VI) are often detected in contaminated soil. Yet, cost-effective remediation technologies have been lacking. In this study, we prepared a type of FeSx based on commercial FeSO4.7H2O and CaSx and tested a microwave-assisted technology based on FeSx for reductive immobilization of high concentrations of Cr(VI) in a field contaminated soil. The as-prepared FeSx particles appeared as a honeycomb-like and highly porous structure. The microwave-assisted FeSx reduction process was able to rapidly reduce the TCLP-based reachability of Cr(VI) from 391.8 to 2.6 mg·L-1. The dosage of FeSx, S/Fe molar ratio, initial moisture content, microwave power, and irradiation time can all affect the treatment effectiveness. After 500 days curing under atmospheric conditions, the TCLP-leached concentration of Cr remained below the regulatory limit of 5 mg·L-1, while other treatments failed to meet the goal. Sx2- or S2- served as the primary electron donors, whereas Fe facilitated the microwave absorption and the formation of the stable final product of FeCr2O4. S and Fe are mostly precipitated in soil. The microwave-assisted FeSx reduction was shown to be an effective approach to rapidly reduce the leachability of Cr(VI) in contaminated soil, especially in heavily contaminated soil.
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Affiliation(s)
- Jianle Wang
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China
| | - Xueming Liu
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China
| | - Zhihua Zhu
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China
| | - Le Yuan
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China
| | - Dongye Zhao
- Auburn University, Department of Civil and Environmental Engineering, Auburn, AL 36849 USA
| | - Hong Deng
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China.
| | - Zhang Lin
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China; School of Metallurgy and Environment, Central South University, Changsha 410083, China
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Li D, Li G, Zhang D. Field-scale studies on the change of soil microbial community structure and functions after stabilization at a chromium-contaminated site. JOURNAL OF HAZARDOUS MATERIALS 2021; 415:125727. [PMID: 34088197 DOI: 10.1016/j.jhazmat.2021.125727] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/14/2021] [Accepted: 03/19/2021] [Indexed: 05/20/2023]
Abstract
Various remediation strategies have been developed to eliminate soil chromium (Cr) contamination which challenges the ecosystem and human health, and chemical stabilization is the most popular one. Limited work focuses on the change of soil microbial community and functions after chemical stabilization. The present study examined the diversity and structure of bacterial, fungal and archaeal communities in 20 soils from a Cr-contaminated site in China after chemical stabilization and ageing. Cr contamination significantly reduced microbial diversity and shaped microbial community structure. After chemical stabilization, bacterial and fungal communities had higher richness and evenness, whereas archaea behaved oppositely. Microbial community structure after stabilization were more similar to uncontaminated soils. Among all environmental variables, pH and Al explained 25.2% and 9.4% of the total variance of bacterial diversity, whereas the major variable affecting fungal community was pH (29.3%). Cr, organic matters, extractable-Al and moisture explained 25.8%, 22.4%, 9.9% and 9.9% of the total variance in archaeal community, respectively. This work for the first time unraveled the change of the whole soil microbial community structures and functions at Cr-contaminated sites after chemical stabilization on field scale and proved chemical stabilization as an effective approach to detoxicate Cr(VI) and recover microbial communities in soils.
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Affiliation(s)
- Danni Li
- School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, China
| | - Guanghe Li
- School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, China
| | - Dayi Zhang
- School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, China.
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Hou R, Wang L, Shen Z, Alessi DS, Hou D. Simultaneous reduction and immobilization of Cr(VI) in seasonally frozen areas: Remediation mechanisms and the role of ageing. JOURNAL OF HAZARDOUS MATERIALS 2021; 415:125650. [PMID: 34088176 DOI: 10.1016/j.jhazmat.2021.125650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/05/2021] [Accepted: 03/10/2021] [Indexed: 06/12/2023]
Abstract
Among the toxic metals, hexavalent chromium [Cr(VI)] has attracted much attention due to its high mobility and toxicity, rendering considerable challenges for long-term remediation. In this study, the soil was collected from a dichromate contaminated industrial site in Liaoning Province, a seasonally frozen area in northern China, and subjected to frequent freeze-thaw cycles. Three additives, including (i) ferrous sulfate; (ii) calcium polysulfide; and (iii) combined biochar and calcium polysulfide were applied to reduce and immobilize Cr(VI) in the soils. The samples underwent 28 days of incubation followed by 16 freeze-thaw cycles. The toxicity characteristic leaching procedure (TCLP) and simulated acid rain leaching were adopted to test the remediation performances. It was observed that all three treatments can significantly reduce and immobilize Cr(VI) after short-term incubation, while biochar with abundant functional groups could adsorb and reduce Cr(VI) effectively. Notably, the concentration of Cr(VI) in TCLP leachates after incubation in combined treatment decreased by 67.87% and 37.27%, respectively, compared with the application of ferrous sulfate or calcium polysulfide alone. Freeze-thaw cycles induced the disintegration of soil particles and increased the risk of contaminant mobilization. Conversely, biochar particles has become finer and even produced nanoparticles with ageing, accompanied by the increase in oxygen-containing surface functional groups. Additionally, the specific surface area increased with the pyrolysis of biochar, which further enhanced the retention of soil colloidal particles and suppressed the migration of contaminants. Therefore, the cumulative release of Cr(VI) in the combined treatment (i.e., 10.97 ~ 32.97 mg/kg) was much lower than that of the other two treatments after freeze-thaw ageing. Overall, the combination of biochar and calcium polysulfide displayed advantages in the reduction and immobilization of Cr(VI), and offered a long-term, effective strategy for the remediation of Cr(VI) contaminated soils in cold regions.
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Affiliation(s)
- Renjie Hou
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Liuwei Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhengtao Shen
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Daniel S Alessi
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton T6G 2E3, Canada
| | - Deyi Hou
- School of Environment, Tsinghua University, Beijing 100084, China.
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Yang Z, Zhang X, Jiang Z, Li Q, Huang P, Zheng C, Liao Q, Yang W. Reductive materials for remediation of hexavalent chromium contaminated soil - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 773:145654. [PMID: 33582355 DOI: 10.1016/j.scitotenv.2021.145654] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/18/2021] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
Chemical reduction of Cr(VI) to Cr(III) by reductive materials is the most widely used technology for the remediation of Cr(VI)-contaminated soil due to its high efficiency, adaptability and low cost. This paper reviews chromium chemistry and the materials that can effectively reduce Cr(VI) to Cr(III) for the remediation of Cr(VI)-contaminated soil, namely iron-bearing reductants, sulfur-based compounds and organic amendments. Moreover, we discuss the corresponding mechanisms involved in the process of immobilization of Cr(VI) in polluted soil, and emphasize the relationship between the materials remediation performance and soil environmental conditions. Besides, perspectives on the potential future researches of novel materials design and technological development in the remediation of Cr(VI) contaminated soil are also put forward.
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Affiliation(s)
- Zhihui Yang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, PR China
| | - Xiaoming Zhang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China
| | - Zhi Jiang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China
| | - Qi Li
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China
| | - Peicheng Huang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China
| | - Chujing Zheng
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China
| | - Qi Liao
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, PR China
| | - Weichun Yang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Lushan South Road 932, Changsha, Hunan 410083, PR China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, PR China.
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12
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Ren L, Wang R, Qin B, Liu D, Sang J, Dong J. Enhanced remediation efficiency of Cr(VI)-contaminated heterogeneous aquifers: Improved sweeping efficiency using shear-thinning fluids. CHEMOSPHERE 2021; 273:129675. [PMID: 33486349 DOI: 10.1016/j.chemosphere.2021.129675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 12/25/2020] [Accepted: 01/16/2021] [Indexed: 06/12/2023]
Abstract
Low permeability zones (LPZs) are typically bypassed when remedial reagents are injected into heterogeneous aquifers, which hinders the in situ remediation. Although shear-thinning polymers have emerged as promising tools to meet this challenge, their applicability in complex remedial systems remains unconfirmed. We investigated the sweeping efficiencies of calcium polysulfide (CPS) into Cr(VI)-contaminated LPZs using xanthan gum (XG) as the model shear-thinning polymer. Firstly, the compatibility of XG-CPS fluids and their reduction capacities toward Cr(VI) were demonstrated based on batch experiments. The removal rates of Cr(VI) exceeded 85% in the presence of 250-2000 mg/L of XG. Besides, XG-CPS fluids exhibited a greater impact on the permeability decrease of transmissive zones than that of LPZs as confirmed by sand column experiments. Furthermore, the sweeping efficiencies in LPZs during XG-CPS flooding were investigated by multiple sand tank experiments. The sweeping rate in LPZs (rs) in Cr(VI)-contaminated aquifer (1.68 × 10-3/min) was found to be approximately 11% higher than that of uncontaminated system, and two possible reasons behind this phenomenon were proposed. The spatial distribution profiles of Cr under different XG-CPS flooding conditions were depicted based on 20 representative samples. The results indicated that all Cr(VI) in LPZs can be effectively removed either by displacement or immobilization as Cr(III). The percentages of displaced Cr(VI) and immobilized Cr(III) were calculated to be 65%-75% and 25-35%, respectively. This work demonstrates the applicability of XG-CPS fluids as remedial materials for Cr(VI)-contaminated heterogeneous aquifers and provides novel insights into the role of Cr(VI) in in situ remediation using shear-thinning polymers.
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Affiliation(s)
- Liming Ren
- Research Institute of Petroleum Processing, SINOPEC, Beijing, 100083, PR China.
| | - Ruoyu Wang
- Research Institute of Petroleum Processing, SINOPEC, Beijing, 100083, PR China
| | - Bing Qin
- Research Institute of Petroleum Processing, SINOPEC, Beijing, 100083, PR China
| | - Dengfeng Liu
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130021, PR China
| | - Junqiang Sang
- Research Institute of Petroleum Processing, SINOPEC, Beijing, 100083, PR China
| | - Jun Dong
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130021, PR China.
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13
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Prasad S, Yadav KK, Kumar S, Gupta N, Cabral-Pinto MMS, Rezania S, Radwan N, Alam J. Chromium contamination and effect on environmental health and its remediation: A sustainable approaches. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 285:112174. [PMID: 33607566 DOI: 10.1016/j.jenvman.2021.112174] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 12/15/2020] [Accepted: 02/08/2021] [Indexed: 05/08/2023]
Abstract
Chromium (Cr) is a trace element critical to human health and well-being. In the last few decades, its contamination, especially hexavalent chromium [Cr(VI)] form in both terrestrial and aquatic ecosystems, has amplified as a result of various anthropogenic activities. Chromium pollution is a significant environmental threat, severely impacting our environment and natural resources, especially water and soil. Excessive exposure could lead to higher levels of accumulation in human and animal tissues, leading to toxic and detrimental health effects. Several studies have shown that chromium is a toxic element that negatively affects plant metabolic activities, hampering crop growth and yield and reducing vegetable and grain quality. Thus, it must be monitored in water, soil, and crop production system. Various useful and practical remediation technologies have been emerging in regulating chromium in water, soil, and other resources. A sustainable remediation approach must be adopted to balance the environment and nature.
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Affiliation(s)
- Shiv Prasad
- Centre for Environment Science and Climate Resilient Agriculture, Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Krishna Kumar Yadav
- Institute of Environment and Development Studies, Bundelkhand University, Kanpur Road, Jhansi, 284128, India.
| | - Sandeep Kumar
- Centre for Environment Science and Climate Resilient Agriculture, Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Neha Gupta
- Institute of Environment and Development Studies, Bundelkhand University, Kanpur Road, Jhansi, 284128, India
| | - Marina M S Cabral-Pinto
- Geobiotec Research Centre, Department of Geoscience, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Shahabaldin Rezania
- Department of Environment and Energy, Sejong University, Seoul, 05006, South Korea
| | - Neyara Radwan
- Faculty of Economics & Administration, King Abdulaziz University, Jeddah, Saudi Arabia; Mechanical Department, Faculty of Engineering, Suez Canal University, Ismailia, Egypt
| | - Javed Alam
- Kind Abdullah Institute for Nanotechnology, King Saud University, Riyadh, 11451, Saudi Arabia
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14
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Hu S, Li D, Qin S, Man Y, Huang C. Interference of sulfide with iron ions to the analysis of Cr(Ⅵ) by Method 3060a & Method 7196a. JOURNAL OF HAZARDOUS MATERIALS 2020; 398:122837. [PMID: 32485505 DOI: 10.1016/j.jhazmat.2020.122837] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 04/14/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
When Cr(Ⅵ)-contaminated soil was remediated with sulfide, due to incomplete reaction and overdose, excess sulfide could remain in the soil inducing unacceptable underestimation of residual Cr(Ⅵ) analysis, which would get worse when iron ions were introduced in. Unfortunately, the quality control policy of Method 3060a cannot distinguish the difference between real zero and false zero residual Cr(Ⅵ) when their spike recoveries are zero. This paper systematically investigated the sulfide-induced Cr(Ⅵ) reduction in Cr(Ⅵ) analysis by Method 3060a & Method 7196a. Experimental results indicate that the sulfide-Cr(Ⅵ) reaction mainly occurs during alkaline digestion and pH adjustment processes, and iron ions as an electron transfer carrier between sulfide and Cr(Ⅵ) can catalyze the redox reaction during alkaline digestion. Besides, the high temperature in alkaline digestion significantly accelerates the redox reaction which usually is negligible at room temperature. Sulfur of high concentrations in remediated soils can also cause unacceptable underestimation of Cr(Ⅵ) due to the production of sulfide ions by disproportionation reaction in alkaline digestion. This paper also provides a method to eliminate sulfide ions from alkaline digestion solution before pH adjustment and suggests some possible solutions to the ferrous or sulfide-induced Cr(Ⅵ) analysis bias.
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Affiliation(s)
- Siyang Hu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
| | - Dong Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-environment of Ministry of Education, Chongqing University, Chongqing 400044, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China.
| | - Shiqiang Qin
- College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
| | - Yidong Man
- College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China
| | - Chuan Huang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-environment of Ministry of Education, Chongqing University, Chongqing 400044, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400044, PR China.
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15
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Zhang T, Wang T, Wang W, Liu B, Li W, Liu Y. Reduction and stabilization of Cr(VI) in soil by using calcium polysulfide: Catalysis of natural iron oxides. ENVIRONMENTAL RESEARCH 2020; 190:109992. [PMID: 32763276 DOI: 10.1016/j.envres.2020.109992] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/15/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
Cr(VI)-contaminated soils could be remediated by using calcium polysulfide (CPS), while natural iron oxides as a main composition of soil would influence the pathways of the remediation. Through kinetic batch tests, the kinetics of Cr(VI) removal from soil, the effects of the contents of natural iron oxides, soil environmental conditions and mechanisms of Cr(VI) removal by using CPS with the presence of natural iron oxides were investigated. The results show that the removal of Cr(VI) by using CPS in soil fitted the pseudo-second-order model best, and the appearance of goethite increased the apparent rate constant from 0.0002 kg mg-1 h-1 to 0.0005 kg mg-1 h-1. The presence of iron oxides enhanced the removal of Cr(VI) by using CPS, and an extended reductive atmosphere of soil was created. The enhancement of Cr(VI) removal increased with the contents of iron oxides from 0 to 9 g kg-1, and declined from 9 to 12 g kg-1. Acidic environment favored the removal of Cr(VI) from soil by using CPS with or without the iron oxides compared to neutral soil and increased it from 87% to 100% because of proton-consuming reactions and electrostatic attraction. Twenty-nine percent of exchangeable and bound-to-carbonates species of chromium declined after the remediation, while 24% bound-to-iron-and-manganese-oxide species increased simultaneously. The findings of the study indicate that natural iron oxides in soils catalyze the reduction of Cr(VI) in soil and facilitate significantly the remediation of Cr(VI)-contaminated soil by using CPS.
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Affiliation(s)
- Tong Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, China
| | - Tao Wang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, China
| | - Wanyu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, China
| | - Bin Liu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, China
| | - Wei Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, China
| | - Yuanyuan Liu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, China.
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16
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Wang X, Li L, Yan X, Meng X, Chen Y. Processes of chromium (VI) migration and transformation in chromate production site: A case study from the middle of China. CHEMOSPHERE 2020; 257:127282. [PMID: 32531491 DOI: 10.1016/j.chemosphere.2020.127282] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/25/2020] [Accepted: 05/30/2020] [Indexed: 06/11/2023]
Abstract
The migration and redox transformation processes of toxic Cr(VI) in the upper and deep soil of chromate-polluted site are of great importance for the environmental risk control and soil remediation. In this study, soils from surface to deep (around 30-60 m) and the groundwater in a typical abandoned chromate production plant site which has experienced decades of contamination were both sampled and analyzed. The results show that the soil in the leaching workshop of Cr(VI), dichromate transformation workshop and chromium slag dumping ground exhibits severe contamination of chromium and the pollution has extended to the groundwater, causing serious pollution in groundwater too. The vertical migration and transformation of Cr(VI) in the soil layer are mainly affected by the soil permeability, organic matter content and the amount of water passing through the soil layer. During the downward migration, Cr(VI) tends to be retained by the clay layer and further accumulates around the depth of 5-10 m where the concentrations of both hexavalent and total Cr reach maximum values, and then continues to diffuse from the accumulation layer towards the deeper soil. Accompanying with the reduction of Cr(VI) by organic matter in the soil, the Cr(III) exists at various depths. When the depth is below the groundwater level of saturated aquifer, the distribution of chromium in the soil and groundwater reaches leaching and redox equilibrium due to the long-term interaction between the soil and groundwater.
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Affiliation(s)
- Xingrun Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China
| | - Lei Li
- College of Resources and Environment, Southwest University, Chongqing, 400715, PR China; Chongqing Engineering Research Center of Rural Cleaning, Chongqing, 400716, PR China.
| | - Xianghua Yan
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China
| | - Xiaoguang Meng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - Yucheng Chen
- College of Resources and Environment, Southwest University, Chongqing, 400715, PR China; Chongqing Engineering Research Center of Rural Cleaning, Chongqing, 400716, PR China
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17
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Roles of natural iron oxides in the promoted sequestration of chromate using calcium polysulfide: pH effect and mechanisms. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2019.116350] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Zhang X, Wilson JH, Lawson AJ, Hohenstein EG, Jans U. Stereoisomer specific reaction of hexabromocyclododecane with reduced sulfur species in aqueous solutions. CHEMOSPHERE 2019; 226:238-245. [PMID: 30928716 DOI: 10.1016/j.chemosphere.2019.03.134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 06/09/2023]
Abstract
The individual degradation rates of the three dominant stereoisomers (α, β, γ) of hexabromocyclododecane (HBCDD) with bisulfide and polysulfides were investigated at pH 9 in methanol/water solutions at two different temperatures (25 °C and 40 °C). Under all conditions investigated, α-HBCDD reacts 10 to 20 times slower with bisulfide than β-HBCDD and γ-HBCDD. The difference in reactivity of HBCDD isomers can be explained by the different populations of stable conformers with large dihedral angle between the vicinal bromine atoms. It was also observed that the reaction of HBCDD with polysulfides is about six times faster than with bisulfide. The experiments performed in solvent mixtures with increased water content at 40 °C indicated that the reaction of HBCDD with bisulfide is faster with higher percentage of water. The much slower abiotic reaction of α-HBCDD compared to β-HBCDD and γ-HBCDD could potentially contribute to the fact that α-HBCDD is more persistent in the environment than γ-HBCDD. Only one isomer of tetrabromocyclododecene (TBCDe-5) was identified as a degradation product of the reaction of HBCDD with reduced sulfur species. TBCDe-5 itself reacts about ten times slower with bisulfide and twenty times slower with polysulfide than HBCDD. The study demonstrates that polysulfides and bisulfides can reduce HBCDD sufficiently in natural anoxic environments and the dominant pathway for the degradation of HBCDD by reduced sulfur species is very likely to be the reductive debromination of vicinal dibromides via concerted anti-elimination.
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Affiliation(s)
- Xianmiao Zhang
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY, 10016, United States
| | - John H Wilson
- Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States
| | - Ariel J Lawson
- Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States
| | - Edward G Hohenstein
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY, 10016, United States; Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States
| | - Urs Jans
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY, 10016, United States; Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States.
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19
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Shi M, Li J, Li X, Liang D, Guo C, Zheng J, Deng B. Reductive Immobilization of Hexavalent Chromium by Polysulfide-Reduced Lepidocrocite. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b01055] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mei Shi
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, China
- College of Natural Resources and Environment, Northwest A&F University, No. 3 Taicheng Road, Yangling, Shaanxi 712100, China
| | - Jiao Li
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, China
| | - Xinyang Li
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, China
| | - Dongli Liang
- College of Natural Resources and Environment, Northwest A&F University, No. 3 Taicheng Road, Yangling, Shaanxi 712100, China
| | - Caiyang Guo
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, China
| | - Jianzhong Zheng
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, China
| | - Baolin Deng
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, Missouri 65211, United States
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20
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Leachability and Stability of Hexavalent-Chromium-Contaminated Soil Stabilized by Ferrous Sulfate and Calcium Polysulfide. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8091431] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ferrous sulfate (FeSO4) and calcium polysulfide (CaS5) stabilization are practical approaches to stabilizing hexavalent chromium (Cr(VI))-contaminated soil. The leachability and stability of Cr(VI) and Cr are important factors affecting the effectiveness of stabilized Cr(VI)-contaminated soil. This study compared the leachability and stability of Cr(VI) and Cr in Cr(VI)-contaminated soil stabilized by using FeSO4 and CaS5. The contaminated soil was characterized before and after stabilization, and the effectiveness of FeSO4 and CaS5 stabilization was assessed using leaching, bioaccessibility, alkaline digestion, sequential extraction, and X-ray diffraction tests. Results showed that FeSO4 and CaS5 significantly reduced the leachability and Cr(VI) content in the contaminated soil. The acid-buffering capacity and stability (leachability, bioaccessibility, speciation distribution, and mineral composition) of the Cr(VI)/Cr and Cr(VI) content of CaS5 were better than those of FeSO4. This study demonstrated that CaS5 had a better effect than FeSO4 on the stabilization of Cr(VI) in Cr(VI)-contaminated soil. The CaS5 significantly enhanced the stabilization and immobilization of Cr(VI) and reduced its leachability and toxicity.
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21
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Liu P, Ptacek CJ, Elena KMA, Blowes DW, Gould WD, Finfrock YZ, Wang AO, Landis RC. Evaluation of mercury stabilization mechanisms by sulfurized biochars determined using X-ray absorption spectroscopy. JOURNAL OF HAZARDOUS MATERIALS 2018; 347:114-122. [PMID: 29304450 DOI: 10.1016/j.jhazmat.2017.12.051] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 12/16/2017] [Accepted: 12/19/2017] [Indexed: 06/07/2023]
Abstract
The application of biochar to treat mercury (Hg) in the environment is being proposed on an increasing basis due to its widespread availability and cost effectiveness. However, the efficiency of Hg removal by biochars is variable due to differences in source material composition. In this study, a series of batch tests were conducted to evaluate the effectiveness of sulfurized biochars (calcium polysulfide and a dimercapto-related compound, respectively) for Hg removal; Hg-loaded biochars were then characterized using synchrotron-based techniques. Concentrations of Hg decreased by >99.5% in solutions containing the sulfurized biochars. Sulfur X-ray absorption near-edge structure (XANES) analyses indicate a polysulfur-like structure in polysulfide-sulfurized biochar and a thiol-like structure (shifted compared to dimercapto) in the dimercapto-sulfurized biochar. Micro-X-ray fluorescence (μ-XRF) mapping and confocal X-ray micro-fluorescence imaging (CXMFI) analyses indicate Hg is distributed primarily on the edges of sulfurized biochar and throughout unmodified biochar particles. Hg extended X-ray absorption fine structure (EXAFS) analyses show Hg in enriched areas is bound to chlorine (Cl) in the unmodified biochar and to S in sulfurized biochars. These results indicate that Hg removal efficiency is enhanced after sulfurization through the formation of strong bonds (Hg-S) with S-functional groups in the sulfurized biochars.
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Affiliation(s)
- Peng Liu
- School of Environmental Studies, China University of Geosciences, 388 Lumo Rd., Wuhan, Hubei, 430074, PR China; Department of Earth and Environmental Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada
| | - Carol J Ptacek
- Department of Earth and Environmental Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada.
| | - Krista M A Elena
- Department of Earth and Environmental Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada
| | - David W Blowes
- Department of Earth and Environmental Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada
| | - W Douglas Gould
- Department of Earth and Environmental Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada
| | - Y Zou Finfrock
- Science Division, Canadian Light Source Inc., 44 Innovation Boulevard, Saskatoon, SK, S7N 2V3, Canada; CLS@APS Sector 20, Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439, USA
| | - Alana O Wang
- Department of Earth and Environmental Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada
| | - Richard C Landis
- I. Du Pont de Nemours and Company, 974 Centre Road, Wilmington, DE 19805, USA
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22
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23
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Li Y, Cundy AB, Feng J, Fu H, Wang X, Liu Y. Remediation of hexavalent chromium contamination in chromite ore processing residue by sodium dithionite and sodium phosphate addition and its mechanism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 192:100-106. [PMID: 28157612 DOI: 10.1016/j.jenvman.2017.01.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 01/09/2017] [Accepted: 01/14/2017] [Indexed: 05/07/2023]
Abstract
Large amounts of chromite ore processing residue (COPR) wastes have been deposited in many countries worldwide, generating significant contamination issues from the highly mobile and toxic hexavalent chromium species (Cr(VI)). In this study, sodium dithionite (Na2S2O4) was used to reduce Cr(VI) to Cr(III) in COPR containing high available Fe, and then sodium phosphate (Na3PO4) was utilized to further immobilize Cr(III), via a two-step procedure (TSP). Remediation and immobilization processes and mechanisms were systematically investigated using batch experiments, sequential extraction studies, X-ray diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). Results showed that Na2S2O4 effectively reduced Cr(VI) to Cr(III), catalyzed by Fe(III). The subsequent addition of Na3PO4 further immobilized Cr(III) by the formation of crystalline CrPO4·6H2O. However, addition of Na3PO4 simultaneously with Na2S2O4 (via a one-step procedure, OSP) impeded Cr(VI) reduction due to the competitive reaction of Na3PO4 and Na2S2O4 with Fe(III). Thus, the remediation efficiency of the TSP was much higher than the corresponding OSP. Using an optimal dosage in the two-step procedure (Na2S2O4 at a dosage of 12× the stoichiometric requirement for 15 days, and then Na3PO4 in a molar ratio (i.e. Na3PO4: initial Cr(VI)) of 4:1 for another 15 days), the total dissolved Cr in the leachate determined via Toxicity Characteristic Leaching Procedure (TCLP Cr) testing of our samples was reduced to 3.8 mg/L (from an initial TCLP Cr of 112.2 mg/L, i.e. at >96% efficiency).
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Affiliation(s)
- Yunyi Li
- College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China; School of Ocean and Earth Science, University of Southampton, Southampton SO14 3ZH, UK
| | - Andrew B Cundy
- School of Ocean and Earth Science, University of Southampton, Southampton SO14 3ZH, UK.
| | - Jingxuan Feng
- Center for Environmental Education and Communications of Ministry of Environmental Protection, 100029, PR China
| | - Hang Fu
- College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China
| | - Xiaojing Wang
- College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China
| | - Yangsheng Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China.
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24
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Li Y, Wang W, Zhou L, Liu Y, Mirza ZA, Lin X. Remediation of hexavalent chromium spiked soil by using synthesized iron sulfide particles. CHEMOSPHERE 2017; 169:131-138. [PMID: 27870934 DOI: 10.1016/j.chemosphere.2016.11.060] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 11/06/2016] [Accepted: 11/11/2016] [Indexed: 06/06/2023]
Abstract
Carboxymethyl cellulose (CMC) stabilized microscale iron sulfide (FeS) particles were synthesized and applied to remediate hexavalent chromium (Cr(VI)) spiked soil. The effects of parameters including dosage of FeS particles, soil moisture, and natural organic matter (NOM) in soil were investigated with comparison to iron sulfate (FeSO4). The results show that the stabilized FeS particles can reduce Cr(VI) and immobilize Cr in soil quickly and efficiently. The soil moisture ranging from 40% to 70% and NOM in soil had no significant effects on Cr(VI) remediation by FeS particles. When molar ratio of FeS to Cr(VI) was 1.5:1, about 98% of Cr(VI) in soil was reduced by FeS particles in 3 d and Cr(VI) concentration decreased from 1407 mg kg-1 to 16 mg kg-1. The total Cr and Cr(VI) in Toxicity Characteristic Leaching Procedure (TCLP) leachate were reduced by 98.4% and 99.4%, respectively. In FeS particles-treated soil, the exchangeable Cr fraction was mainly converted to Fe-Mn oxides bound fraction because of the precipitation of Cr(III)-Fe(III) hydroxides. The physiologically based extraction test (PBET) bioaccessibility of Cr was decreased from 58.67% to 6.98%. Compared to FeSO4, the high Cr(VI) removal and Cr immobilization efficiency makes prepared FeS particles a great potential in field application of Cr(VI) contaminated soil remediation.
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Affiliation(s)
- Yujie Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environment of Ministry of Education, Chongqing University, Chongqing, 400044, PR China
| | - Wanyu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environment of Ministry of Education, Chongqing University, Chongqing, 400044, PR China
| | - Liqiang Zhou
- Chongqing Solid Waste Management Center, Chongqing, 401147, PR China
| | - Yuanyuan Liu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environment of Ministry of Education, Chongqing University, Chongqing, 400044, PR China.
| | - Zakaria A Mirza
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Xiang Lin
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China
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25
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Dahlawi SM, Siddiqui S. Calcium polysulphide, its applications and emerging risk of environmental pollution-a review article. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:92-102. [PMID: 27761854 DOI: 10.1007/s11356-016-7842-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 10/04/2016] [Indexed: 06/06/2023]
Abstract
Easy availability, preparation technique, and economic value make calcium polysulphide (CaS x ) a very useful inorganic chemical for various field and industrial applications. In this article, disparate applications of CaS x solution have been reviewed to suggest potential and future consolidation. This article also encompasses the physiochemical properties and production of CaS x solution, with critical appraisal on research focusing on CaS x application in agriculture industries and removal of potentially toxic elements (PTEs) from the environment. The kinetics of CaS x , technical issues associated with optimization of its dosage and environmental fate is also discussed in detail. This study covers almost all of the peer-reviewed research that has been performed since 1914. Some of the critiques in this article include the lack of integration between the exposure effect and the efficiency of treatment method, effects of oxidizing environments on the long-term performance of CaS x solution, and kinetics of CaS x solution with the PTEs. The working model of CaS x with PTEs is still system dependent, and therefore cannot be used with other applications. The kinetics of CaS x is described in detail with various phase stoichiometric reactions. Environmental fate is discussed based on applications, government reports, peer-reviewed articles and kinetics of CaS x , which provides a clear picture of emerging contaminants in the environment in relation to the insect resistance and ecotoxicology. Real time, lab based research articles are needed to identify toxicity limits of CaS x in environment in order to describe its effective permissible limit in environmental system. This review article provides a risk assessment of environmental pollution by CaS x based on its physicochemical characteristic, stoichiometry, kinetics, field, and industrial applications.
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Affiliation(s)
- Saad Mohammed Dahlawi
- Department of Environmental Health, College of Applied Medical Sciences, University of Dammam, P. O Box 2435, Dammam, 31441, Kingdom of Saudi Arabia.
| | - Samreen Siddiqui
- Department of Physical & Environmental Sciences, The Coastal Health and Water Quality (C-HaWQ) Laboratory, Texas A&M University Corpus Christy, Corpus Christi, TX, 78412, USA
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26
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Wang SY, Chen SC, Lin YC, Kuo YC, Chen JY, Kao CM. Acidification and sulfide formation control during reductive dechlorination of 1,2-dichloroethane in groundwater: Effectiveness and mechanistic study. CHEMOSPHERE 2016; 160:216-229. [PMID: 27376861 DOI: 10.1016/j.chemosphere.2016.06.066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/21/2016] [Accepted: 06/17/2016] [Indexed: 06/06/2023]
Abstract
To enhance the reductive dechlorination of 1,2-dichloroethane (DCA) in groundwater, substrate injection may be required. However, substrate biodegradation causes groundwater acidification and sulfide production, which inhibits the bacteria responsible for DCA dechlorination and results in an odor problem. In the microcosm study, the effectiveness of the addition of ferrous sulfate (FS), desulfurization slag (DS), and nanoscale zero-valent iron (nZVI) on acidification and sulfide control was studied during reductive dechlorination of DCA, and the emulsified substrate (ES) was used as the substrate. Up to 94% of the sulfide was removed with FS and DS addition (0.25 wt%) (initial DCA concentration = 13.5 mg/L). FS and DS amendments resulted in the formation of a metal sulfide, which reduced the hydrogen sulfide concentration as well as the subsequent odor problem. Approximately 96% of the DCA was degraded under reductive dechlorination with nZVI or DS addition using ES as the substrate. In microcosms with nZVI or DS addition, the sulfide concentration was reduced to less than 15 μg/L. Acidification can be controlled via hydroxide ions production after nZVI oxidation and reaction of free CaO (released from DS) with water, which enhanced DCA dechlorination. The quantitative polymerase chain reaction results confirmed that the microcosms with nZVI added had the highest Dehalococcoides population (up to 2.5 × 10(8) gene copies/g soil) due to effective acidification control. The α-elimination mechanism was the main abiotic process, and reductive dechlorination dominated by Dehalococcides was the biotic mechanism that resulted in DCA removal. More than 22 bacterial species were detected, and dechlorinating bacteria existed in soils under alkaline and acidic conditions.
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Affiliation(s)
- S Y Wang
- Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - S C Chen
- Department of Life Sciences, National Central University, Chung-Li, Taiwan
| | - Y C Lin
- Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Y C Kuo
- Formosa Petrochemical Co., Kaohsiung, Taiwan
| | - J Y Chen
- Formosa Petrochemical Co., Kaohsiung, Taiwan
| | - C M Kao
- Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
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27
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Shi J, Chen H, Arocena JM, Whitcombe T, Thring RW, Memiaghe JN. Elemental sulfur amendment decreases bio-available Cr-VI in soils impacted by leather tanneries. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 212:57-64. [PMID: 26840517 DOI: 10.1016/j.envpol.2016.01.045] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 12/01/2015] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
This study investigated the potential use of elemental S (S(0)) to convert Cr-VI to Cr-III which should decrease the bio-availability hence, toxicity of Cr-VI in soils. The bio-available fraction of Cr in soil was measured by phosphate buffer extraction (PBE) and the results showed that the fraction is about 10% of the total Cr-VI and varied from 12.8 to 42.5 mg kg(-1). The addition of 4.0 mg g(-1) S(0) decreased PBE Cr-VI to <0.4 mg kg(-1) limit established for Cr-VI toxicity in soils. Synchrotron-based X-ray absorption near-edge structure (XANES), X-ray fluorescence (XRF) and micro-XRD revealed that Cr-III was the dominant species (99% of total Cr) and Cr was retained by hematite and goethite in soil. Fe-containing minerals may have provided sufficient protection to render the dominant Cr-III species biochemically inert to redox processes in soils. It is concluded that S(0)amendment is a promising approach to remediate Cr-VI contaminated soils.
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Affiliation(s)
- Jingjing Shi
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, Zhejiang Province 325035, China; Environmental Science and Engineering Programs, University of Northern British Columbia, Prince George, BC V2N 4Z9, Canada.
| | - Hualin Chen
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, Zhejiang Province 325035, China.
| | - Joselito M Arocena
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, Zhejiang Province 325035, China; Environmental Science and Engineering Programs, University of Northern British Columbia, Prince George, BC V2N 4Z9, Canada.
| | - Todd Whitcombe
- Environmental Science and Engineering Programs, University of Northern British Columbia, Prince George, BC V2N 4Z9, Canada.
| | - Ronald W Thring
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, Zhejiang Province 325035, China; Environmental Science and Engineering Programs, University of Northern British Columbia, Prince George, BC V2N 4Z9, Canada.
| | - Jeff Nze Memiaghe
- Environmental Science and Engineering Programs, University of Northern British Columbia, Prince George, BC V2N 4Z9, Canada.
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