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Wu Z, Liu D, Deng Y, Pang R, Wang J, Qin T, Yang Z, Qiu R. Remediation of Cr(VI)-contaminated soil by CS/PPy coupling with Microbacterium sp. YL3. JOURNAL OF HAZARDOUS MATERIALS 2024; 475:134580. [PMID: 38865829 DOI: 10.1016/j.jhazmat.2024.134580] [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: 03/02/2024] [Revised: 04/14/2024] [Accepted: 05/08/2024] [Indexed: 06/14/2024]
Abstract
In this research, a new material, chitosan/polypyrrole (CS/PPy), was synthesized and linked with the Cr(VI)-reducing bacterial strain YL3 to treat Cr(VI)-polluted soil. The findings demonstrated that the synergistic application of strain YL3 and CS/PPy achieved the greatest reduction (99.6 %). During the remediation process, CS/PPy served as a mass-storage and sustained release agent in the soil, which initially decreased the toxic effects of high concentrations of Cr(VI) on strain YL3, thereby enhancing the Cr(VI) reduction efficiency of strain YL3. These combined effects significantly mitigated Cr(VI) stress in the soil and restored enzyme activities. Furthermore, wheat growth in the treated soil also significantly improved. High-throughput sequencing of the microorganisms in the treated soil revealed that CS/PPy was not only effective at removing Cr(VI) but also at preserving the original microbial diversity of the soil. This suggests that the combined treatment using strain YL3 and CS/PPy could rehabilitate Cr(VI)-contaminated soil, positioning CS/PPy as a promising composite material for future bioremediation efforts in Cr(VI)-contaminated soils.
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Affiliation(s)
- Zhiguo Wu
- College of Chemical Engineering and Materials, Tianjin University of Science and Technology, Tianjin 300457, China; College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Dan Liu
- College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ying Deng
- College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Runyi Pang
- College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Jinjin Wang
- College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Tian Qin
- College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Zongzheng Yang
- College of Chemical Engineering and Materials, Tianjin University of Science and Technology, Tianjin 300457, China; College of Oceanography and Environment, Tianjin University of Science and Technology, Tianjin 300457, China.
| | - Rongliang Qiu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Laboratory for Lingnan Modern Agriculture, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China.
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Jia J, Yao L, Xiao B, Fan X, Wang X, Liu Y, Wu Y, Hu L, Zhang D. Mechanisms and influential factors of soil chromium long-term stability by an accelerated aging system after chemical stabilization. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:134994. [PMID: 38909472 DOI: 10.1016/j.jhazmat.2024.134994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/25/2024] [Accepted: 06/19/2024] [Indexed: 06/25/2024]
Abstract
Chemical stabilization is one of the most widely used remediation strategies for chromium (Cr)-contaminated soils by reducing Cr(VI) to Cr(III), and its performance is affected by human and natural processes in a prolonged period, challenging long-term Cr stability. In this work, we established a method for evaluating the long-term effectiveness of remediation of Cr-contaminated soils, and developed an accelerated aging system to simultaneously simulate acid rain leaching and freeze-thaw cycles. The mechanisms and influencing factors of long-term (50-year) change in soil Cr speciation were unravelled after stabilization with Metafix®. Chemical stabilization remarkably decreased the contents of Cr(VI)soil, Crtotal-leach and Cr(VI)leach, among which the removal rate of Cr(VI) in soil was up to 89.70 %, but it also aggravated soil Cr instability. During the accelerated aging process, Crtotal-leach change rates in chemically stabilized soil samples were 0.0462-0.0587 mg/(L·a), and soil Cr became instable after 20-year accelerated aging. The proportion of Cr bound to organic matter and residual Cr increased in soil, and exchangeable Cr decreased. Linear combination fitting results of XANES also showed that Cr(VI) and Cr3+ were transformed into OM-Cr(III), Fh-Cr(III) and CrFeO3 after restoration. During the accelerated aging process, acid rain leaching activated Cr(III) and dissolved Cr(VI), whereas freeze-thaw cycle mainly affected OM-Cr. Chemical stabilization, acid rain leaching and aging time were the major factors influencing the stability of soil Cr, and the freeze-thaw cycle promoted the influence of acid rain leaching. This study provided a new way to explore the long-term effectiveness and instability mechanisms at Cr-contaminated site after chemical stabilization.
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Affiliation(s)
- Jianli Jia
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, PR China
| | - Linying Yao
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, PR China
| | - Bing Xiao
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, PR China
| | - Xiaolu Fan
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xinzi Wang
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yunpeng Liu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yu Wu
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, PR China
| | - Lei Hu
- Department of Civil Engineering, New Mexico State University, Las Cruces, NM 88003, USA
| | - Dayi Zhang
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun 130021, PR China; College of New Energy and Environment, Jilin University, Changchun 130021, PR China; Key Laboratory of Regional Environment and Eco-restoration, Ministry of Education, Shenyang University, Shenyang 110044, PR China.
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Jain S, Tembhurkar AR. Optimizing nutrients from fly ash-amended soil through microbial-assisted phytoremediation using response surface methodology. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:145. [PMID: 38214830 DOI: 10.1007/s10661-023-12273-8] [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: 11/14/2023] [Accepted: 12/29/2023] [Indexed: 01/13/2024]
Abstract
Nutrients are vital ingredients to boost plant health. The availability of nutrients is limited in fly ash (FA) waste to properly implement phytoremediation. The research explored the integration of microbes and treated wastewater irrigation in phytoremediation to provide the necessary nutrients for plant growth in fly ash-amended soils. The Box-Behnken method was used to design the experimental layout for the pot study. Response surface methodology (RSM) was applied as the optimization approach to model predictions for nutrient accumulation. The implemented pot study attained the highest morphological indicators with a plastochron index of 33.40, an absolute growth rate of 2.63 cm/day, and a leaf area of 2681.68 cm2 and attained maximum biomass of 24.91 g for the treatments that included a mid-range of the variables. The combination of FA 14.98%, microbial dose 4.07 mL, and treated wastewater as the irrigation source was found to be the optimized combination for nitrogen and phosphorus accumulation of 212.4 and 8.867 mg/L.
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Affiliation(s)
- Sandeep Jain
- Civil Engineering Department, Visvesvaraya National Institute of Technology, Nagpur, 440010, India.
| | - Ajay R Tembhurkar
- Civil Engineering Department, Visvesvaraya National Institute of Technology, Nagpur, 440010, India
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Liu N, Zhang Y, Zheng C, Tang C, Guan J, Guo Y. Sulfidated nanoscale zero valent iron for in situ immobilization of hexavalent chromium in soil and response of indigenous microbes. CHEMOSPHERE 2023; 344:140343. [PMID: 37788746 DOI: 10.1016/j.chemosphere.2023.140343] [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: 07/02/2023] [Revised: 09/27/2023] [Accepted: 09/30/2023] [Indexed: 10/05/2023]
Abstract
This study aimed to investigate the immobilization efficiency of sulfidated nanoscale zero valent iron on Cr(VI) in soil. Reactions between sulfidated nanoscale zero valent iron and Cr(VI) in soil system and effects of sulfidated nanoscale zero valent iron on microbes had been demonstrated. Solid characterization results confirmed the incorporation of sulfur into nanoscale zero valent iron. Furthermore, the main oxidation products of iron after the reactions were magnetite, goethite and lepidocrocite. Fe-Cr complexes indicated that Cr(VI) was reduced to Cr(III). The results of 16 S rRNA gene analysis indicated that the sulfidated nanoscale zero valent iron had a limited bactericidal effect but further stimulated the sulfite reductase gene population, representing its positive effect for the soil remediation. The study showed that some microflora such as Protobacteria were promoted, while others community such as Firmicutes, were depressed. Furthermore, Cr mainly converted from a high toxic state such as exchangeable (EX) to less bioavailable state such as iron-manganese oxides bound (OX) and organic matter-bound (OM), thus reducing the toxicity of Cr when sulfidated nanoscale zero valent iron was added. High immobilization efficiency of the Cr(VI) compared to nanoscale zero valent iron indicated an improvement on selectivity and reactivity after sulfidation. Overall, sulfidated nanoscale zero valent iron was promising for the immobilization of Cr(VI) immobilization soil.
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Affiliation(s)
- Nuo Liu
- Shanghai Collaborative Innovation Centre for WEEE Recycling, School of Resources and Environmental Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
| | - Yufei Zhang
- Research Group of Water Pollution Control and Water Reclamation, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Chunli Zheng
- Shanghai Collaborative Innovation Centre for WEEE Recycling, School of Resources and Environmental Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
| | - Chenliu Tang
- Research Group of Water Pollution Control and Water Reclamation, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Jie Guan
- Shanghai Collaborative Innovation Centre for WEEE Recycling, School of Resources and Environmental Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
| | - Yaoguang Guo
- Shanghai Collaborative Innovation Centre for WEEE Recycling, School of Resources and Environmental Engineering, Shanghai Polytechnic University, Shanghai, 201209, China.
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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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Xiao W, Zhang Q, Zhao S, Chen D, Gao N, Huang M, Ye X. Citric acid secretion from rice roots contributes to reduction and immobilization of Cr(VI) by driving microbial sulfur and iron cycle in paddy soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 854:158832. [PMID: 36122705 DOI: 10.1016/j.scitotenv.2022.158832] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 09/09/2022] [Accepted: 09/13/2022] [Indexed: 06/15/2023]
Abstract
Root exudates released by plants can promote microbial growth and activity, thereby affecting the transformation and availability of soil pollutants. However, the effects of the root exudates of rice plants on chromium (Cr) transformation in paddy soils and the underlying mechanisms are yet to be elucidated properly. The present study investigated how rice root exudates interact with rhizosphere microorganisms to influence the transformation of Cr and explored the key components in root exudates that affect Cr(VI) reduction. The results showed that the addition of root exudate and citric acid markedly decreased soil pH and increased dissolved organic carbon content that created favorable conditions and provided sufficient electron donors for Cr(VI) reduction, thereby greatly facilitating the reduction of Cr(VI) and the transformation of HOAc-extractable Cr into more stable oxidizable and residual Cr. Additionally, Desulfovibrio-related sulfate-reducing bacteria, Thiobacillus-related sulfide-oxidizing bacteria, and Geobacter-related Fe(III)-reducing bacteria were enriched with the addition of root exudate and citric acid. Among them, sulfate would be reduced by Desulfovibrio to sulfide, which would be further utilized by Thiobacillus to reduce Cr(VI), thereby enabling the continuous reduction of Cr(VI); simultaneously, Geobacter would sustain the reduction of Cr(VI) by reducing Fe(III) to Fe(II). Furthermore, based on the high-level secretion of citric acid in response to Cr(VI) exposure and the similar effects of root exudates and citric acid on Cr(VI) reduction, it is proposed that citric acid is the key component in rice root exudates that affects Cr(VI) reduction. These results suggest that root exudates (citric acid as the key component) contribute to the reduction and immobilization of Cr(VI) by driving microbial S and Fe cycles, with Desulfovibrio, Thiobacillus, and Geobacter being the keystone genera. The study provides a novel insight into the Fe/S/Cr co-transformation processes with microbial involvement, and the artificial root exudate mixtures designed to reduce Cr(VI).
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Affiliation(s)
- Wendan Xiao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Qi Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Shouping Zhao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - De Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Na Gao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Miaojie Huang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xuezhu Ye
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
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Xiao W, Ye X, Ye Z, Zhang Q, Zhao S, Chen D, Gao N, Huang M. Responses of microbial community composition and function to biochar and irrigation management and the linkage to Cr transformation in paddy soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 304:119232. [PMID: 35364188 DOI: 10.1016/j.envpol.2022.119232] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/25/2022] [Accepted: 03/27/2022] [Indexed: 06/14/2023]
Abstract
Combining biochar with irrigation management to alter the microbial community is a sustainable method for remediating soils contaminated by heavy metals. However, studies on how these treatments promote Cr(VI) reduction are limited, and the corresponding microbial mechanisms are unclear. Therefore, we conducted a pot experiment to explore the responses of soil microbial communities to combined biochar amendment and irrigation management strategies and their involvement in Cr transformation in paddy soils. Six treatments were established using varying concentrations of biochar (0, 1, and 2% [w/w]) combined with two irrigation management strategies (continuous flooding [CF] and dry-wet alternation [DWA]). The results showed that the combined biochar addition and irrigation management strategy significantly altered soil pH, redox potential, organic matter content, and Fe(II) and sulfide concentrations. In addition, the Cr(VI) concentration under CF irrigation management was conspicuously lower (48.2-54.4%) than that under DWA irrigation management. Biochar amendment also resulted in a substantial reduction (8.8-27.4%) in Cr(VI) concentration. Moreover, the changes in soil physicochemical properties remarkably affected the soil microbial community. The microbial diversity and abundance significantly increased with biochar amendment. Furthermore, the combined biochar amendment and CF strategy stimulated the growth of Geobacter- and Anaeromyxobacter-related Fe(III)-reducing bacteria, Gallionella-related Fe(II)-oxidizing bacteria, and Desulfovibro- and Clostridium-related sulfate-reducing bacteria, which simultaneously facilitated the generation of Fe(II) and sulfide, thereby enhancing Cr(VI) reduction. Consequently, our results suggest that the effectively increased abundance of Fe-reducing/oxidizing bacteria and sulfate-reducing bacteria via combined CF irrigation management and biochar addition may be a key factor in reducing Cr(VI) in paddy soil. The keystone genera responsible for Cr(VI) reduction were Geobacter, Anaeromyxobacter, Gallionella, Desulfovibro, and Clostridium. This study provides novel insights into the coupling mechanism of the Fe/S/Cr transformation mediated by Fe-reducing/oxidizing bacteria and sulfate-reducing bacteria.
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Affiliation(s)
- Wendan Xiao
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Xuezhu Ye
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China.
| | - Zhengqian Ye
- College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, 311300, China
| | - Qi Zhang
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Shouping Zhao
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - De Chen
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Na Gao
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Miaojie Huang
- Key Laboratory of Information Traceability for Agricultural Products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
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Gao Y, Wang H, Xu R, Wang YN, Sun Y, Bian R, Li W. Remediation of Cr(VI)-contaminated soil by combined chemical reduction and microbial stabilization: The role of biogas solid residue (BSR). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 231:113198. [PMID: 35033874 DOI: 10.1016/j.ecoenv.2022.113198] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 12/28/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
In this work, the use of chemical reduction combined with microbial stabilization to remediate Cr(VI) in contaminated soil was systematically investigated. The effectiveness, phytotoxicity and microbial diversity resulting from the combination of ferrous sulfate with microbial stabilization by biogas solid residue (BSR) were determined. The stabilization experiments showed that the optimum Cr(VI) conversion rate of 99.92% was achieved with an Fe (II)/Cr(VI) molar ratio of 3:1, a BSR dose of 5.2% (wt), and a water content of 40%. Under these conditions, the residual Cr(VI) content was 0.80 mg/kg, which satisfied the risk screening value (≤ 5.7 mg/kg) for soil contamination of land for general development in China. The remaining Cr(VI) level was stable for 90 days during the chemical reduction and biogenic stabilization process. Moreover, Zucconi test analysis suggested that the soil phytotoxicity to Brassica campestris L. disappeared. The results of microbial diversity analysis indicated that the bacterial community changed significantly during chemical reduction and microbial stabilization processes, and Bacillus, Pseudomonas and Psychrobacter may participate in the reduction of Cr(VI) into Cr(III).
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Affiliation(s)
- Ying Gao
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Huawei Wang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China.
| | - Rong Xu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Ya-Nan Wang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Yingjie Sun
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China.
| | - Rongxing Bian
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Weihua Li
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
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