Environmental Technology & Innovation
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2024
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IF 6.7
Dayong Luo,XiaoSong Tian,Ruxiang Qin
Iron reducing bacterium Acidiphilium cryputum JF-5 was used to biologically load lanthanum on bentonite (BLB) to remove arsenic(V) from solution. By biological reductive release of iron from bentonite and lanthanum loading, new lanthanum-loaded bentonite was prepared and the adsorption efficiency of arsenic(V) was improved from 7.87 mg/g to 22.69 mg/g in bath experiment. The mobilization of the dispersed biologically loaded lanthanum bentonite particles can be described by the Convection-Dispersion Equation. The breakthrough ability of biologically lanthanum-loaded bentonite (BLB) increased by 5.5 times when increasing flow velocities from 90 mL/h to 360 mL/h. When injected BLB into arsenic(V)-containing pre water of quartz column, the concentration of arsenic(V) could quickly decrease the initial concentration of arsenic(V) from 2000 μg/L to lower than limit for drinking water and keep relative stable. Meanwhile, the hydraulic conductivity of treatment system is also improved compared to prinstine bentonite due to iron-deficient in BLB. The results suggest that biologically load lanthanum bentonite may be an effective modified mineral for remediating arsenic(V)-containing soil.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
GEOCHIMICA ET COSMOCHIMICA ACTA
·
2018
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IF 4.69
Tongxu Liu,Dandan Chen,Xiaobo Luo,Xiaomin Li,Fangbai Li
Redox reactions between iron and nitrogen drive the global biogeochemical cycles of these two elements and, concomitantly, change the fate of nutrients in and the mineralogy of the cycles. The microbially mediated NO 3 − -reducing Fe(II) oxidation process (NRFO) plays a key role in Fe/N interactions under neutral-anoxic conditions. Microbially mediated NRFO was considered a biological process, yet recently it has been documented that chemical mechanisms are also at play. However, the relative contributions of biological processes and chemical processes to Fe(II) oxidation remain largely unquantified owing to the co-occurrence of the reactions. Herein, the kinetics and secondary minerals of microbially mediated NRFO by Pseudogulbenkiania sp. strain 2002 and Acidovorax sp. strain BoFeN1 were investigated with acetate as electron donor unless otherwise stated. The results of Cells + NO 3 − suggested the two strains could biologically reduce NO 3 − to NO 3 − /NO x /N 2 O/N 2 and concomitantly oxidize acetate and result in cell growth. Fe(II) oxidation and NO 3 − reduction occurred simultaneously in the presence of Fe(II) (Cells + Fe(II) + NO 3 − ). For strain BoFeN1, the presence of Fe(II) slightly enhanced the NO 3 − reduction, acetate consumption, and cell growth, all of which were substantially retarded by Fe(II) for strain 2002. When compared with the microbial nitrite reduction, the relatively higher rate of chemical reaction between NO 2 − and dissolved Fe(II) confirmed the occurrence of chemodenitrification in the microbially mediated NRFO processes. After 5 days’ incubation, no green rust was observed, and lepidocrocite , goethite , and magnetite were observed with the Cells + Fe(II) + NO 3 − treatment, but only goethite was found with the Fe(II) + NO 2 − . The spectra for the EPSs + Fe(II) treatment suggested that the oxidized c -Cyts in the EPSs could oxidize Fe(II), which show the theoretical capability of taking electrons from Fe(II) into the cells via c -Cyts. A brief model was established by combining the verified reactions of (1) biological reduction of NO 3 − to NO 2 − /NO x /N 2 O/N 2 , (2) Fe(II) oxidation by NO 2 − , and (3) Fe(II) oxidation by c -Cyts in EPSs. Based on the model, the rate constant of Fe(II) oxidation by c -Cyts in EPSs was derived. For nitrite reduction, the relative contribution of biological processes to the nitrite reduction was higher than that of chemodenitrification. For Fe(II) oxidation, the relative contribution of the chemical process via nitrite to Fe(II) oxidation was higher than that of biological processes. These findings provide a quantitative interpretation of the chemodenitrification and biological reactions in the microbially mediated NRFO processes, which could assist the mechanistic understanding of the global biogeochemical cycles of iron and nitrogen in subsurface environments.
研究领域:
微生物学
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环境科学
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地球化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Guangfei Liu,Min Li,Rihong Gu,Lianfeng Wang,Huali Yu,Ruofei Jin,Jiti Zhou,Bin Ma
Incubation of iron-reducing bacteria with Fe(III) could generate •OH to decompose organic pollutants under redox fluctuation conditions. However, the Fe(III)/Fe(II) transformation efficiency and therefore yields of •OH production in systems using Fe(III)-bearing minerals as respiration substrate of bacteria is unsatisfying. Here, we showed that different iron- and iron-copper-based metal–organic frameworks (Fe-MOFs and FeCu-MOFs) can mediate electron transfer from Shewanella oneidensis MR-1 to O 2 through their Fe(III)/Fe(II) cycling during anoxic–oxic transition, resulting in generation of reactive oxygen species including •O 2 – , H 2 O 2 and •OH. While 3 g/L of MIL-101(Fe) demonstrated faster Fe(III)/Fe(II) cycling, better yields of •OH production (69.0 μmol/mmol Fe(II) oxidation) and sulfanilamide removal (81.5 % in 24 h) than iron-bearing minerals and the rest two Fe-MOFs (MIL-53(Fe) and MIL-88B(Fe)), Fe 0.75 Cu 0.25 -B surpassed the performance of MIL-101(Fe) and other FeCu-MOFs with different Fe/Cu ratios, which might be attributed to its larger surface area, higher amounts of associated Fe(II), and synergistic effects between Fe and Cu species. Moreover, both MIL-101(Fe) and Fe 0.75 Cu 0.25 -B maintained structure stability and persistent catalytic activity during four continuous redox cycles in 48 h, the •OH production and sulfanilamide degradation of which exceeded those of one-time operation in the same duration. This study revealed the efficacy of combining bacteria and MOFs for •OH production, and provided promising alternatives for oxidative degradation of contaminants.
研究领域:
环境科学
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微生物学
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材料科学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
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IF 5.589
Rong Chen,Hui Liu,Peng Zhang,Lei Zhao,Kang Ding,Songhu Yuan
Groundwater table fluctuation during natural and anthropogenic processes can facilitate the interaction between oxygen (O 2 ) from the unsaturated zone and ferrous iron (Fe 2+ ) from the saturated zone. In light of previous findings that Fe(III)-reducing bacteria can be killed by the reactive oxidants produced from Fe 2+ oxidation under static oxic conditions, we hypothesize that Fe(III)-reducing bacteria will be attenuated during groundwater table fluctuations. To test this hypothesis, this study explored the variations of cell numbers of Shewanella oneidensis strain MR-1 (MR-1), a typical strain of Fe(III)-reducing bacteria, together with dissolved oxygen (DO) and Fe 2+ , at different points during controlled groundwater table fluctuations in a sand column. The results showed that, during the rise of the water table, O 2 in the pore air was entrapped by the deoxygenated groundwater, and Fe 2+ in the groundwater was oxidized by the entrapped O 2 . In this process, 1.40–2.42 orders of magnitude of viable MR-1 cells were killed at different points in the column. Further investigation proposed that the death of MR-1 is caused by the production of intracellular reactive oxidants, such as O 2 • − and OH•, from the oxidation of adsorbed/absorbed Fe 2+ instead of by bulk reactive oxidants, such as OH• and Fe(IV), produced from the oxidation of aqueous Fe 2+ . The findings here provide new insights for Fe biogeochemical cycling in the redox-dynamic zone.
研究领域:
环境微生物学
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水文学
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生物地球化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
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IF 7.7
Pu Wang,Xiaofeng Liu,Fang Liu,Wei Zhan,Yongdong Chen,Weichen Zhu,Yongqiang Wang,Qiyou Liu,Chunshuang Liu,Jun Lu,Yu Tian
Phosphorus (P) recovery is critical for sustainable resource management, given its non-renewable nature and geopolitical supply risks. This study addresses the limitations of conventional approaches for inducing vivianite crystallization in wastewater, including low yield per unit volume, limited phosphorus recovery efficiency, and low vivianite purity. To overcome these challenges, we propose a two-stage hybrid strategy that combines chemical precipitation with microbially induced recrystallization under semi-solid conditions. In the first stage, iron-based coagulation captures the majority of phosphate as amorphous Fe–P complexes. In the subsequent stage, dissimilatory iron-reducing bacteria (DIRB) facilitate the reduction of Fe(Ⅲ) and drive its recrystallization into vivianite. Compared with liquid-phase crystallization, this approach supports higher P loading, thereby improving spatial efficiency and enhancing vivianite purity. Batch experiments demonstrated that increasing the solid content consistently enhanced the vivianite fraction in the product, achieving a maximum P recovery efficiency of 97.7 % and a vivianite purity of 92.6 %, which is markedly superior to other reported crystallization methods. Microbial community analysis revealed Trichlorobacter and Geobacter are key dissimilatory Fe-reducing genera driving the recrystallization of precipitates to vivianite. Successful application to real sludge digestion liquor confirmed the method's robustness.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
·
IF 10.753
Zexuan He,Jifei Chang,Yujie Feng,Shu Wang,Qing Yuan,Danhui Liang,Jia Liu,Nan Li
Vivianite widely existed in digested sludge and activated sludge as a potential phosphate resource recovered from wastewater treatment plants (WWTPs). As an important product of extracellular electron transfer (EET) and biological iron reduction, the production of vivianite can be enhanced by conductive materials. Carbon nanotubes (CNTs) with excellent electrical conductivity have been reported to promote electron transfer, which was applied in wastewater treatment to accelerate the degradation of the contaminants. However, the impact of CNTs on vivianite formation was barely reported. In this study, the iron reduction, vivianite recovery, and the biotoxicity of CNTs were investigated in order to determine the influence of CNTs towards the vivianite production. The enhancement of vivianite production after CNTs adding reached up to 17 % by promoting the electron transfer between dissimilative iron-reducing bacteria (DIRB) and Fe(III). However, at the initial stage (0–24 h), Fe(III) reduction efficiency decreased by 81 % after inoculating with sewage sludge, which was attributed to CNTs destroying of the cell membrane (as indicated by SEM, CLSM and AFM analysis). The biotoxicity of CNTs stimulated DIRB to secret extracellular polymeric substances (EPS) and form bio-flocs to resist the physical puncture. After 48 h, the proportion of living DIRB in 1000 mg/L CNTs batch increased to 98 %, which was 79 % higher than 12 h. As a result, the vivianite recovery of raw sewage with 1000 mg/L CNTs increased to 44 ± 1 %, which was 33 % higher than that in the CNT-0.
研究领域:
环境科学
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废水处理
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纳米技术
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2022
·
IF 11.889
Kexin Lu,Qian Ping,Qinyuan Lu,Yongmei Li
Effects of fulvic acid (FA) and bovine serum albumin (BSA) on the transformation of ferric phosphate (FePO 4 ) during anaerobic fermentation of waste activated sludge were investigated. Both FA and BSA promoted phosphorus (P) release from FePO 4 . A higher P release efficiency was achieved with FA addition compared with BSA at the same dose although BSA promoted iron (Fe) reduction more effectively. Both FA and BSA contributed to the enrichment of vivianite but hindered P re-precipitation with other ions, and FA affected more significantly. Microbial analysis revealed that FA contributed to the enrichment of iron-reducing bacteria (IRB) transporting electrons indirectly and increased the bioavailable Fe(III) via siderophores; BSA provided more electron donors, thereby enriched IRB transferring electrons directly to Fe(III). This study provides an in-depth understanding of Fe and P transformations in sludge bearing iron-phosphorus compounds and it is of practical value for P recovery as vivianite.
研究领域:
环境科学
·
微生物学
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废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xiaoqiu Lin,Linshan Zheng,Min Zhang,Yue Qin,Xiaolu Liu,Yuanfeng Liu,Huiyu Li,Congju Li
Nanomaterials are ideal for electrode modification to improve the power output of microbial fuel cells (MFCs). The nanomaterials decoration usually needs a conductive binder which faces the problem of high cost and low conductivity, significantly constraining further application. This study successfully fabricated the binder-free Fe nano oxides modified anodes through the solvothermal method. MFC assembled with carbon cloth/Fe nano oxides (M−CC/Fe) achieved the highest maximum power density (471.6 mW m −2 ), dramatically higher than that with carbon cloth (M−CC, 150.4 mW m −2 ), Ni foam/Fe nano oxides (M−NF/Fe, 130.6 mW m −2 ) and Ni foam (M−NF, 16.5 mW m −2 ). The electrochemical catalyzing activity, extracellular electron transfer rate, COD removal efficiency and coulombic efficiency were all improved after Fe nano oxides decoration in MFCs. Fe nano oxides enriched exoelectrogens/iron-reducing bacteria like Geobacter and Comamonas and showed a mutual benefit relationship with them. The formation of stable Fe nano oxide cubes significantly enhanced the electroactive biofilm development and alleviated the corrosion of the electrode substrate. The complementary merits of the carbon-based electrode and Fe nano oxides performed better in stimulating power generation in MFCs. These results provided knowledge of in-situ nanomaterials decoration for advanced anodes, providing suggestions for high-performance resource recovery from wastewater.
研究领域:
环境科学
·
纳米技术
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电化学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Shuyu He,Shaohua Chen,Liwen Zhang,Shanyi Tan,Huizi Wen,Luyao Xi,Xiangru Zuo,Dongyun Du
Dissimilatory iron-reducing bacteria (DIRB) offer an eco-friendly approach to address nanoscale zero-valent iron (nZVI) surface passivation problem, yet their efficacy is limited by the slow direct extracellular electron transfer (EET) between DIRB and Fe(III) oxide passivation layers (Fe( III )OPL). This study demonstrates that natural dissolved humic substances (DHS)-mediated electron shuttling unlocking nZVI reactivity in Shewanella oneidensis MR-1 (MR-1) system for enhance Cr(VI) removal. Seven DHSs from diverse sources were evaluated, revealing that Cr(VI) removal rate constants ( k obs ) correlate strongly with DHS's quinone content (C=O) and electron transfer capacity (ETC), quantified as k obs = 1.66 C C = O − 9.39 ( P < 0.0007) and k obs = 19.37 ETC + 0.74 ( P < 0.0005). DHS-mediated systems achieve 2.0–12.1-fold higher k obs than nZVI/MR-1 alone. The enhancement mechanism of DHS-mediated Cr(VI) removal by nZVI/MR-1 is that DHS effectively facilitates Fe( III )OPL dissolution on the nZVI surface via electron shuttling, maintaining nZVI reactivity and amplifying Fe(II) generation by 1.65-fold. Moreover, DHS stimulates MR-1 to secrete more extracellular polymeric substances (EPS), enhancing Cr(VI) adsorption and reduction. This work elucidates DHS's dual role in maintaining nZVI activity and amplifying Cr(VI) removal by nZVI/MR-1, while establishing a predictive framework linking DHS molecular traits parameters to Cr(VI) removal kinetic, offering sustainable strategies for heavy metal-contaminated water bodies remediation by integrating biogeochemical and material engineering principles.
研究领域:
环境科学
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生物地球化学
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材料工程
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微生物学
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水体修复技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Siqi Tong,Dan Chen,Ping Mao,Xinbai Jiang,Aiwu Sun,Zhixiang Xu,Xiaodong Liu,Jinyou Shen
A novel magnetic hydrochar synthesized from Fenton sludge (FS) and sewage sludge (SS) was employed in the anaerobic decolorization of acid orange 7 (AO7). The stable presence of Fe 3 O 4 in magnetic hydrochar was confirmed by physicochemical characterization. The degradation efficiency of AO7 in the anaerobic system with the addition of hydrochar prepared in an optimal proportion (SS:FS=1:3, named as HC-1:3) could reach 98.55%, which was 1.91 times higher than the control system. Particularly, superior electrical conductivity, electron transport system activity and azo reductase activity of the sludge in anaerobic system with HC-1:3 were achieved. The redox of Fe(Ⅲ)/Fe(Ⅱ) in anaerobic system was realized by dissimilatory iron-reducing bacteria enriched with HC-1:3. According to the six-cycle batch experiments and 120-day continuous-flow UASB experiments, the addition of HC-1:3 into the anaerobic system facilitated the diversity of microbiological community and increased the ecological stability of anaerobic system. The possible electron transfer mechanism involving in the magnetic hydrochar-based anaerobic system for AO7 removal was speculated preliminarily. The as-prepared magnetic hydrochar not only showed a promising future in anaerobic system for recalcitrant contaminants degradation, but also provided a new approach for the resource utilization of FS and SS.
研究领域:
环境科学
·
废水处理
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材料科学
·
生物技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）