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Li F, Li M, Liu Y, Li F, Tian J. Citric acid-induced photochemical behavior of Cr(III)-substituted ferrihydrite: Fe and Cr release, mineral transformation and reactive oxygen species generation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171778. [PMID: 38513872 DOI: 10.1016/j.scitotenv.2024.171778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 02/20/2024] [Accepted: 03/15/2024] [Indexed: 03/23/2024]
Abstract
Cr(III)-substituted ferrihydrite (Fh-Cr(III)) is widespread in the surrounding environment of mining areas. Fh-Cr(III) is unstable and susceptible to the influence of environmental factors, such as dissolved organic matter (DOM) and light, so Cr species embedded in mineral crystal layers are likely to have more profound negative effects on the environment with the photochemical behaviors of minerals. However, the photochemical behaviors of Fh-Cr(III) in the presence of DOM remains poorly understood. For this reason, citric acid (CA) was chosen as the representative DOM to study its combined effects with visible light irradiation on Fh-Cr(III) dissolution and phase transition. The results showed that CA hindered the agglomeration of Fh-Cr(III) particles, thereby slowing the phase transition of Fh-Cr(III). However, CA exacerbated the release of Fe and Cr by maintaining Fh-Cr(III) under unstable crystal structure. Moreover, due to the occurrence of ligand-metal charge transfer (LMCT) in (CA)n-Fh-Cr(III) formed on the Fh-Cr(III) surface, the synergistic effect between CA and light irradiation greatly promoted the dissolution of Fh-Cr(III). In the mixed system of Fh-Cr(III) (3 g/L) and CA (5 mM) at initial pH 3.0, the maximum concentrations of TFe and TCr were 18.17 and 5.68 mg/L after 6 h of light reaction, which were 1.82 and 3.62 times of those in the corresponding system in the darkness. Meanwhile, the Fe(III)/Fe(II) cycling in solution and solid surfaces was affected by various reactive oxygen species (ROS) generated from the LMCT process, in which the photoproduced Fe(II) further accelerated Cr(III) dissolution under acidic solution. The fast release of Cr(III) may pose greater danger to the environment as the more toxic Cr(VI) can be easily formed through the oxidation of dissolved Cr(III). This work offers fresh insights into the migration and transformation of Cr elements in the natural environment.
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Affiliation(s)
- Fan Li
- Department of Environmental Science Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Mengke Li
- Department of Environmental Science Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Yun Liu
- Department of Environmental Science Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
| | - Feng Li
- Department of Environmental Science Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Jiang Tian
- Department of Environmental Science Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
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Guo Z, Wang L, Feng B, Zhang L, Zhang W, Dong D. Degradation of enoxacin with different dissociated species during the transformation of ferrihydrite-antibiotic coprecipitates. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 913:169797. [PMID: 38181939 DOI: 10.1016/j.scitotenv.2023.169797] [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: 11/06/2023] [Revised: 12/04/2023] [Accepted: 12/28/2023] [Indexed: 01/07/2024]
Abstract
Ferrihydrite acts as a natural reservoir for nutrient elements, organic matter, and coexisting pollutants through adsorption and coprecipitation. However, the degradation of emerging fluoroquinolone antibiotics during the transformation of ferrihydrite coprecipitates, especially those with various dissociated species, remains insufficiently explored. In this study, Enoxacin (ENO), employed as a model antibiotic, was introduced to prepare ferrihydrite-ENO coprecipitates. The influence of coprecipitated ENO on the transformation of the ferrihydrite-ENO coprecipitate was investigated across different pH conditions. The results revealed that ferrihydrite-ENO coprecipitates thermodynamically transformed into more stable goethite and/or hematite under all pH conditions. In neutral and alkaline conditions, ENO promoted the transformation of coprecipitates into goethite while hindering hematite formation. Conversely, under acidic conditions, ENO directly obstructed the transformation of coprecipitates into hematite. Different dissociated species of ENO displayed distinct degradation pathways. The cationic form of ENO exhibited a greater tendency for hydroxylation and defluorination, while the zwitterion form leaned toward piperazine ring oxidation, with limited preference for quinolone ring oxidation. The anionic form of ENO exhibited the fastest degradation rate. It is essential to emphasize that the toxicity of the degradation products was intricately connected to the specific reaction sites and the functional groups they acquired post-oxidation. These findings offer fresh insights into the role of antibiotics in coprecipitation, the transformation of ferrihydrite coprecipitates, and the fate of coexisting antibiotics.
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Affiliation(s)
- Zhiyong Guo
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Liting Wang
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China; School of Materials and Environmental Engineering, Chengdu Technological University, Chengdu, Sichuan 610031, China.
| | - Baogen Feng
- China Three Gorges Corporation, Hubei 430010, China
| | - Liwen Zhang
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Wenming Zhang
- Dept of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Deming Dong
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China
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Zhang X, Su C, Zhang Y, Lai S, Han S, Zhang X, Zheng J. Mineralogical characteristics of root iron plaque and its functional mechanism for regulating Cr phytoextraction of hyperaccumulator Leersia hexandra Swartz. ENVIRONMENTAL RESEARCH 2023; 228:115846. [PMID: 37024027 DOI: 10.1016/j.envres.2023.115846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/24/2023] [Accepted: 04/03/2023] [Indexed: 05/16/2023]
Abstract
Leersia hexandra Swartz (L. hexandra) is a promising hyperaccumulator for Cr pollution remediation, but whether its Cr phytoextraction is subject to the root surface-attached iron plaque (IP) remains unclear. In this research, the natural and artificial IPs were proven to be comprised of small amounts of exchangeable Fe as well as carbonate Fe, and dominantly Fe minerals involving amorphous two-line ferrihydrite (Fh), poorly crystalline lepidocrocite (Le) and highly crystalline goethite (Go). The Fe content in the artificial IPs augmented with increasing induced Fe(II) concentration, and the 50 mg/L Fe(II) led to the identical Fe content and different component proportions of artificial IP (Fe50) and natural IP. Fh was consisted of highly aggregated nanoparticles, and the aging of Fh caused its phase conversion to rod-like Le and Go. The Cr(VI) adsorption results of Fe minerals corroborated the coordination of Cr(VI) onto the Fh surface and the significantly greater equilibrium Cr(VI) adsorption amount of Fh over Le and Go. The greatest Cr(VI) reduction capacity of Fh among three Fe minerals was found to be related to its most abundant surface-adsorbed Fe(II) content. The results of hydroponic experiment of L. hexandra showed that the presence of IP facilitated the Cr(VI) removal by L. hexandra during the cultivation period of 10-45 days, and consequently, compared to the Fe0 group (without IP), around 60% of increase in the Cr accumulation of shoots was achieved by Fe50 group. The findings of this work are conductive to furthering our understanding of IP-regulated Cr phytoextraction of L. hexandra.
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Affiliation(s)
- Xuehong Zhang
- College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China; Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, 541004, China
| | - Chang Su
- College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China
| | - Yuanyuan Zhang
- College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China; Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, 541004, China.
| | - Simin Lai
- College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China
| | - Shuo Han
- College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China
| | - Xingran Zhang
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Junjian Zheng
- College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China; Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, 541004, China.
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Dai G, Li X, Fu H, Wang F, Cui Z, Zhao R, Wang L. A novel oxalated zero-valent iron nanoparticle for Pb(II) removal from aqueous solution: Performance and synergistic mechanisms. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Lv Y, Liu J, Chen C, Lin X, Wu X, Chen Q, He H, Zhu R. Enhanced immobilization of phosphate by ferrihydrite during the photoreductive dissolution process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155835. [PMID: 35550904 DOI: 10.1016/j.scitotenv.2022.155835] [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: 01/30/2022] [Revised: 04/19/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
The surface interactions of iron (hydr)oxides with various environmental chemicals play a vital role in controlling their environmental transport and fate. As a bioessential element, phosphorus and its biogeochemical cycling are usually controlled by its adsorption on iron (hydr)oxides. Photoreductive dissolution of iron (hydr)oxides can change their surface structure and properties, but its influence on the adsorption of phosphate remains unknown. Here, an enhanced removal of phosphate during the photoreductive dissolution of ferrihydrite (Fh) was investigated. The Kd value of phosphate adsorption on Fh under light irradiation is evidently larger than that in the dark (21 vs 13 L/g). Zeta potential determination in combination with X-ray photoelectron spectroscopy analysis suggested that the released Fe2+ from Fh surface during photoreductive dissolution can be oxidized to Fe3+, which then co-adsorb with phosphate back to Fh surface, enhancing the immobilization of phosphate on Fh. In situ ATR-FTIR results disclosed that light irradiation could further facilitate the formation of ternary complexes and surface precipitation on Fh, even after the increment of phosphate adsorption becoming negligible in the dark, and the relative content of surface precipitation increased evidently. The desorption ratio of phosphate from the irradiated Fh sample was reduced, which should be attributed to a high content of surface precipitation that can tightly bind phosphate on Fh. The findings of this study highlight an important yet previously unappreciated pathway that light irradiation can enhance the immobilization of phosphate on iron (hydr)oxides.
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Affiliation(s)
- Ying Lv
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Liu
- Macau University of Science and Technology, State Key Laboratory of Lunar and Planetary Sciences, Avenida Wai Long, Taipa, Macau, China
| | - Chaorong Chen
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoju Lin
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao Wu
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingze Chen
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongping He
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Runliang Zhu
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China..
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Zhang T, Chen X, Wang Y, Li L, Sun Y, Wang Y, Zeng X. The stability of poorly crystalline arsenical ferrihydrite after long-term soil suspension incubation. CHEMOSPHERE 2022; 291:132844. [PMID: 34767854 DOI: 10.1016/j.chemosphere.2021.132844] [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: 08/23/2021] [Revised: 11/02/2021] [Accepted: 11/07/2021] [Indexed: 06/13/2023]
Abstract
2- Line ferrihydrite (Fh) is widely used as a robust amendment for rapid arsenic removal or remediation in water or soil. However, the poorly crystalline phase of Fh is unstable and leads to arsenic leaching after long-term submergence in reductive aquatic and soil environments. In this study, the synthesized As(V)-bound Fh was characterized by various spectral approaches to investigate the factors that may affect the variation in As(V)-Fh in long-term continuously submerged soil suspensions. The X-ray diffraction (XRD) results showed that hematite was the main product and that goethite was the byproduct after 360 d of incubation. Approximately 12-17% and 4-5% Fh were transformed at As/Fe mole ratios of 0.005 and 0.05, respectively. After 360 d of incubation, the hematite morphology was clearly observed by scanning electron microscopy (SEM), and the As(V)-Fh surface areas were also decreased by 17.3-27.6% and 11.9-16.6% for As/Fe mole ratios of 0.005 and 0.05, respectively. In a comparison of the two tested soils (soils sampled in Sichuan Province (SC) and Hunan Province (HN)), As(V)-Fh transformed faster in HN soil suspensions, and more hematite and goethite were formed. Furthermore, during the incubation period, As(V) was transformed to As(III), and both species were released into the suspension from the As(V)-Fh surface. It was suggested that soil pH and Fe(II) concentration were key factors controlling the As(V)-Fh transformation process, and the differences between the two soils were due to the different soil pH values and contents of available Fe. Arsenic release was mainly caused by Fh transformation and ligand competition with soil organic matter (SOM).
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Affiliation(s)
- Tuo Zhang
- Institute of Agricultural Environment and Sustainable Development, Chinese Academy of Agriculture Sciences/Key Laboratory of Agro-Environment, Ministry of Agriculture, Beijing, 100081, China; College of Environmental Science & Engineering, China West Normal University, Nanchong, Sichuan, 637009, China
| | - Xinyi Chen
- College of Environmental Science & Engineering, China West Normal University, Nanchong, Sichuan, 637009, China
| | - Yu Wang
- College of Environmental Science & Engineering, China West Normal University, Nanchong, Sichuan, 637009, China
| | - Lijuan Li
- Institute of Agricultural Environment and Sustainable Development, Chinese Academy of Agriculture Sciences/Key Laboratory of Agro-Environment, Ministry of Agriculture, Beijing, 100081, China
| | - Yuanyuan Sun
- Key Laboratory of Plant Physiology and Developmental Regulation, Guizhou Normal University, Guiyang, Guizhou, 550025, China
| | - Yanan Wang
- Institute of Agricultural Environment and Sustainable Development, Chinese Academy of Agriculture Sciences/Key Laboratory of Agro-Environment, Ministry of Agriculture, Beijing, 100081, China
| | - Xibai Zeng
- Institute of Agricultural Environment and Sustainable Development, Chinese Academy of Agriculture Sciences/Key Laboratory of Agro-Environment, Ministry of Agriculture, Beijing, 100081, China.
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Yuan Y, Wei X, Yin H, Zhu M, Luo H, Dang Z. Synergistic removal of Cr(VI) by S-nZVI and organic acids: The enhanced electron selectivity and pH-dependent promotion mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127240. [PMID: 34844358 DOI: 10.1016/j.jhazmat.2021.127240] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 08/30/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
The effects of organic acids on hexavalent chromium (Cr(VI)) removal by reduced iron-based materials have been extensively studied. Nevertheless, the promotion mechanism from the perspective of the electron transfer process is still unclear. Herein, sulfidated nanoscale zero-valent iron (S-nZVI) and the selected organic acids, citric acid (containing both -OH and -COOH groups) and oxalic acid (containing only -COOH groups), showed significant synergistic promotion effects in Cr(VI) removal. The FeS and FeS2 on S-nZVI surface could enhance the Cr(VI) reduction as the reductive entity and electron conductor. Furthermore, even though the reactivity of FeS with Cr(VI) is higher than that with FeS2, the Cr(VI) removal efficiency by FeS2 was much higher than that by FeS with organic acids. Under neutral and alkaline conditions (pH 6.0-8.0), organic acids promoted the diffusion, adsorption and complexation of Cr(VI) on S-nZVI surface, thus enhancing the electron selectivity towards Cr(VI). However, when the solution pH changed to acidic conditions (pH 4.0), organic acids facilitated the dissolution of Fe(II) ions from S-nZVI and enhanced the electron utilization towards Cr(VI) via the fast Fe(III) reduction process. This study provided a new insight into the Cr(VI) removal, which was beneficial to understand the application boundaries of S-nZVI for Cr(VI) remediation.
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Affiliation(s)
- Yibo Yuan
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006 Guangdong, China
| | - Xipeng Wei
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006 Guangdong, China; Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Hua Yin
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006 Guangdong, China.
| | - Minghan Zhu
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006 Guangdong, China
| | - Haoyu Luo
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006 Guangdong, China
| | - Zhi Dang
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006 Guangdong, China
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Shi Y, Zhong R, Zhou L, Lan Y, Guo J. Photoreductive dissolution of schwertmannite loaded with Cr(VI) induced by tartaric acid. CHEMOSPHERE 2021; 276:130127. [PMID: 33690038 DOI: 10.1016/j.chemosphere.2021.130127] [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: 11/08/2020] [Revised: 02/04/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
Schwertmannite (SCH) as an adsorbent for Cr(VI) removal has been widely investigated. However, there are limited reports on photoreduction driven dissolution of SCH loaded with Cr(VI) (SCH-Cr(VI)) and the fate of Cr(VI) in the presence of dissolved organic matter (DOM). In this study, the effect of tartaric acid (TA) on the stability of SCH-Cr(VI) exposed to simulated solar radiation was examined. The results demonstrated that TA could greatly enhance the release of the dissolved total Fe (TFe) from SCH-Cr(VI). Conversely, the dissolved total Cr (TCr) obviously declined. Low pH promoted the liberation of TFe and TCr. The presence of ions including Al3+, Ca2+, K+ and CO32- exerted different impact on the photoreductive dissolution of SCH-Cr(VI) induced by TA. On the basis of the species distribution of iron and chromium and the characterization of the solid samples, the underlying mechanism is proposed for the transformation and the fate of Cr(VI). Cr(VI) was reduced to Cr(III) by Fe(II) generated from Fe(III)-TAn via ligand to metal charge transfer. The produced Cr(III) was adsorbed by SCH or co-precipitates with Fe(III). Thus, this study helps us to gain an insight into the mobility and fate of Cr(VI) in acid mining drainage containing DOM, and will help design remediation strategies for Cr contamination.
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Affiliation(s)
- Ying Shi
- College of Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Ruixue Zhong
- College of Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Lixiang Zhou
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Yeqing Lan
- College of Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China.
| | - Jing Guo
- College of Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China.
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Yuan C, Zhang Y, Yao J, Liu Q, Kong FG. Facile Synthesis of Polyethylene Glycol@Tannin-Amine Microsphere towards Cr(VI) Removal. Polymers (Basel) 2021; 13:1035. [PMID: 33810378 PMCID: PMC8037244 DOI: 10.3390/polym13071035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/22/2021] [Accepted: 03/22/2021] [Indexed: 01/16/2023] Open
Abstract
Herein, a synthetic strategy for a rough microsphere Cr(VI)-adsorbent via the reaction of tannic acid (TA) and 1,6-hexanediamine (HA) and using polyethylene glycol (PEG) as surface modifier was presented. This adsorbent was characterized by a Fourier Transform Infrared spectrometer (FTIR), thermogravimetic analysis (TGA), X-ray photoelectron spectroscopy (XPS), etc. Certain factors, including contact time, PEG@poly(tannin-1,6-hexanediamine) (PEG@PTHA) dosage, initial concentration, and experimental temperature affecting the Cr(VI) adsorption performance of adsorbent were explored. PEG@PTHA can adsorb Cr and the Cr(VI) was reduced up to Cr(III) due to the existence of phenolic hydroxyl groups. Its adsorption capacity can reach up to 300 mg/g within 10 min and approximately 100% removal percentage below the initial concentration of 100 mg/L. Its behavior matched well with the Langmuir isotherm model and pseudo-second-order kinetic model. A PEG@PTHA adsorbent with maximum adsorption capacity (450 mg/g) has great prospects in Cr(VI)-sewage treatment.
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Affiliation(s)
| | | | | | - Qinze Liu
- State Key Laboratory of Biobased Material and Green Papermaking, School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China; (C.Y.); (Y.Z.); (J.Y.)
| | - Fan-Gong Kong
- State Key Laboratory of Biobased Material and Green Papermaking, School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China; (C.Y.); (Y.Z.); (J.Y.)
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