ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2025
·Vol. 47
·期 8
·1-20
·
IF 3.8
Hu Zhengchun,Huang Xinrui,Shen Wu,Guo Minghao,Liao Bing
Leakage and migration of landfill leachate are often accompanied by complex biogeochemical processes that form a continuous series of redox zones in the leachate plume. Nitrogen in leachate, especially NH 4 ⁺-N, is one of the most important pollutants contributing to groundwater contamination. While traditional landfill pollution prevention and control measures often have difficulty effectively addressing the complex migration and transformation behaviors of NH 4 ⁺-N in leachate, an in-depth study of the migration and transformation processes of NH 4 ⁺-N in the redox compartment is crucial for the development of accurate and efficient pollution prevention and control strategies. In this study, static transformation experiments, dynamic simulated column experiments and high-throughput sequencing techniques were used to systematically investigate the migration and transformation processes of NH₄⁺-N in the redox bands of a simulated landfill. The results showed that in the NH 4 ⁺-N transformation experiment, the soil in the simulated oxidation zone had the strongest ability to transform NH 4 ⁺-N, with the NH 4 ⁺-N concentration decreasing from 40 to 0.03 mg/L, whereas the sterilization treatment completely suppressed the transformation process of NH 4 ⁺-N in the OZ. The NH 4 ⁺-N in the continuous redox zone completely penetrated the simulated soil column on the 7th day, and the maximum effluent concentration was stable in the range of 1530 ± 30 mg/L. The trends of NH 4 ⁺-N in each independent redox zone were consistent, with the TZ having the richest microbial community abundance and number of species, and some Acidobacteria were able to reduce Fe(III) under anoxic conditions and interact with the organic matter, which effectively contributed to the cycling of Fe within the TZ. These findings indicate that there are significant differences in the biogeochemical cycling process of NH 4 ⁺-N in different redox zone environments, and this study provides a new research perspective for a deeper understanding of the biogeochemical cycling mechanism of the elements in landfills and an important scientific basis for the prevention, control, and remediation of landfill pollution.
研究领域:
环境科学
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微生物学
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水文学
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土壤化学
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产品关联
DOI
PubMed
高影响因子
Environmental Technology & Innovation
·
2021
·
IF 5.263
Yansong Zhang,Zehai Yu,Yunshuang Hu,Caifeng Song,Fuwei Li,Wen He,Xiaofeng Wang,Zhixia Li,Hongfei Lin
Magnetic polyvinyl alcohol–sodium alginate–diatomite (PVA–SA-diatomite) composite carriers for immobilized microorganisms were prepared for removal of NH 4 + -N from effluents. The mass transfer efficiency, chemical stability, and NH 4 + -N removal efficiency of the carriers were investigated. The amount of each ingredient added significantly affected the performance of the carriers. The optimal concentrations of PVA, SA, diatomite , and Fe 3 O 4 were 10%, 1%, 1%, and 2%, respectively. The obtained carrier achieved a NH 4 + -N removal efficiency of 72.5% after reaction for 12 h, which was 31.8% higher than that with the non-magnetic carrier. The removal of NH 4 + -N was attributed to the cooperative action among non-magnetic ingredients, magnetic ingredients, and microorganisms. The adsorptions of NH 4 + -N by non-magnetic ingredients and Fe 3 O 4 contributed 21.2% and 25.5%, respectively, and microorganism metabolism contributed 53.2% to NH 4 + -N removal. The novel texture structure of the carrier leads to improved mass transfer of nutrients and stable activity of microorganisms. Nitrification followed the first-order reaction for low concentration of effluents and zero-order reaction for high concentration of effluents. The reaction rate increased with increasing initial NH 4 + -N concentration. The magnetic carrier was applicable for a long time. These results show the great potential of the developed carrier for industrial applications.
研究领域:
环境工程
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水处理
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生物技术
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Chuanming Zhang,Chunyang Shen,Zhenggang Huang,Hongxin Xu,Yaxiong Zeng,Baohong Guan
Ammonia nitrogen (NH 4 + -N), which exists in the dominant form of ammonium ion (NH 4 + ) under the pH of 6.5–8.5, is one of the regular indexes and the most important pollutants in drinking water. The selective conversion of NH 4 + -N into harmless substances is urgently needed and also a great challenge. Herein we propose a new NH 4 + -N conversion pathway based on a catalytic ozonation process with birnessite-type MnO 2 (δ-MnO 2 ) catalysts. The δ-MnO 2 exhibits a superior performance for NH 4 + -N (1.0 mg/L) removal in adsorption (8.26 %) and oxidation (44.6 %) as well as up to 95.2 % of N 2 selectivity, surpassing almost all the reported O 3 -based catalysts. Unlike the traditional radical oxidation, a singlet oxygen ( 1 O 2 )-dominated nonradical oxidation pathway is confirmed for the efficiently selective conversion of NH 4 + -N to N 2 through the successive dehydrogenation, leading to a 15.0-fold enhancement in NH 4 + -N oxidation rate compared with ozone oxidation. The Mn(III)/Mn(IV) redox sites and surface lattice oxygen in δ-MnO 2 act as the active sites promoting the decomposition of O 3 into •O 2 − and then 1 O 2 via electrons transfer. In application, δ-MnO 2 catalytic ozonation effectively removes NH 4 + -N in real drinking water and presents excellent stability. This work finds a nonradical reaction mechanism in catalytic ozonation for NH 4 + -N selective conversion to N 2 , and solidly solves the problem of low-concentration NH 4 + -N removal from drinking water under the limited pH of 6.5–8.5 condition.
研究领域:
环境科学
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水处理
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催化
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污染物去除
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产品关联
DOI
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Yuanping Fang,Congli Chen,Bin Cui,Haiyan Li,Dandan Zhou
Frequent occurrence of trace antibiotics in reclaimed water is concerning, which inevitably causes aquifer contamination in the case of managed aquifer recharge (MAR). Global governments have formulated strict reclaimed water standards to ensure the safety of water reuse. Recent studies have found that improved antibiotics removal is intimately associated with high ammonia-oxidizing activity. However, the role of NH 4 + -N in the removal of residual antibiotics of reclaimed water during MAR remains unknown. NH 4 + -N removal and the effects of ammonia oxidation on antibiotics biodegradation in the aquifer are the most significant facts for solving the above collision. In this work, the effects of NH 4 + -N (0, 1 and 5 mg/L) in a model refractory antibiotic (oxacillin (OXA), 100 μg/L) attenuation were deciphered by employing three individual simulated MAR columns, which so called N0, N1 and N5. The results showed that 5 mg/L NH 4 + -N in influent upregulated the abundance of amo genes by 28.9 %-68.0 % in N5. And the enriched functional genes encoding key degradation enzymes enhanced the OXA removal by 18.7 % and alleviated the oxidative stress caused by antibiotics. Subsequently, antibiotic resistance genes (ARGs), mobile gene elements (MGEs) and human bacterial pathogens (HBPs) abundance were all significantly decreased. Moreover, the intimate association between ammonia-oxidizing microorganisms (AOM) and candidate OXA degraders based on microbial network analysis further supported the significance of AOM on OXA biodegradation. This study provides comprehensive evidence that appropriate amounts of NH 4 + -N are beneficial in antibiotics and antibiotic resistance risk reduction, providing compelling insights for refine NH 4 + -N recharge limitation.
研究领域:
环境科学
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水资源管理
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微生物学
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生物技术
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
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2022
·
IF 8.943
Jian Zhao,Shangbiao Fang,Weixiao Qi,Huijuan Liu,Jiuhui Qu
Biodegradation is regarding as the most important organic micro-pollutants (OMPs) removal mechanism during riverbank filtration (RBF), but the OMPs co-metabolism mechanism and the role of NH 4 + -N during this process are not well understood. Here, we selected atenolol as a typical OMP to explore the effect of NH 4 + -N concentration on atenolol removal and the role of ammonia oxidizing bacteria (AOB) in atenolol biodegradation. The results showed that RBF is an effective barrier for atenolol mainly by biodegradation and adsorption. The ratio of biodegradation and adsorption to atenolol removal was dependent on atenolol concentration. Specifically, atenolol with low concentration (500 ng/L) is almost completely removed by adsorption, while atenolol with higher concentration (100 μg/L) is removed by biodegradation (51.7%) and adsorption (30.8%). Long-term difference in influent NH 4 + -N concentrations did not show significant impact on atenolol (500 ng/L) removal, which was mainly dominated by adsorption. Besides, AOB enhanced the removal of atenolol (100 μg/L) as biodegradation played a more crucial role in removing atenolol under this concentration. Both AOB and heterotrophic bacteria can degrade atenolol during RBF, but the degree of AOB's contribution may be related to the concentration of atenolol exposure. The main reactions occurred during atenolol biodegradation possibly includes primary amide hydrolysis, hydroxylation and secondary amine depropylation. About 90% of the bio-transformed atenolol was produced as atenolol acid. AOB could transform atenolol to atenolol acid by inducing primary amide hydrolysis but failed to degrade atenolol acid further under the conditions of this paper. This study provides novel insights regarding the roles played by AOB in OMPs biotransformation during RBF.
研究领域:
环境科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
Water
·
2022
·Vol. 14
·期 5
·718
·
IF 3.53
Wan Liu,Shan Chen,Han Zhou,Xianyun Wang,Houtao Xu,Liqing Wang,Wei Zhang,Lijing Chen
Sulfonamides (SAs) are the most common and bio-refractory antibiotics detected in surface water systems, which cause long-term toxic effects on aquatic organisms. This study used the combination of a BiVO4photocatalyst and freshwater micro-green alga (Dictyosphaeriumsp.) to remove sulfadiazine (SD) and sulfamethazine (SM2) at an initial concentration of 5 mg/L (1:1v/v) for 7 days. We set up three gradient concentrations of BiVO4(0.5, 1 and 2 g/L) combined with the same concentration (80 mg/L) ofDictyosphaeriumsp. and then prepared corresponding concentrations of pure BiVO4and pure microalgae as controls. We evaluated the ability of BiVO4andDictyosphaeriumsp. combined technology to remove SAs by observing the removal efficiency of antibiotics and explained the degradation mechanism of antibiotics and the key role of microalgae by studying the changes of reactive oxygen species (ROS) and inorganic ions (nitrogen, sulfur). The results showed that the degradation rate of these two SAs in the 0.5 g/L BiVO4–algae group could reach >96% within 7 d, which was higher than that in the 2 g/L BiVO4group (93%) and the algae group (28%). The increased degradation efficiency of SAs in BiVO4and microalgae systems was mainly due to the increased amount of ROS. Meanwhile, more SAs were degraded to inorganic compounds such as NH4+-N, NO3−-N and SO42−-S under ROS stress. It was found that microalgae can absorb the degradation products of antibiotics such as NH4+-N for their own growth, thereby reducing the toxicity of antibiotic by-products. In addition, BiVO4had no damaging effect on the autofluorescence intensity of the microalgae. Our study provides an efficient and eco-economic approach to remove antibiotics using visible-light irradiation in aquatic environments and provides new insights into the biological removal of other antibiotic contaminants in aquatic environments.Keywords:Dictyosphaeriumsp.;BiVO4;sulfamethazine;sulfadiazine;reactive oxygen species;NH4+-N
研究领域:
环境科学
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水生生态学
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光催化
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微生物学
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DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2019
·Vol. 95
·期 1
·63-72
·
IF 2.659
Jinlan Xu,Lu Li,Juan Du,Huifang Wang
BACKGROUND Many studies have reported that most Fenton pre-oxidation steps either do more damage to the indigenous hydrocarbon degraders (IHD) or produce lower concentrations of ammonium-nitrogen (NH 4 + -N) during Fenton oxidation combined with bioremediation for oil-contaminated soils, which causes the subsequent bioremediation to be unsustainable and poor. The aim of the present study was to find an instant Fenton pre-oxidation for the efficient sustainable biodegradation of long-chain alkanes, and to determine the ratio ( K ) of residual concentration of NH 4 + -N to residual population of IHD that can reach a balance after this instant Fenton pre-oxidation. RESULTS Five Fenton oxidation experiments were carried out with iron bound to soil organic matter (SOM). On this basis, a 75-day field experiment of instant Fenton pre-oxidation with K = 46 combined with bioremediation was performed. Experimental results showed that a similar efficient biodegradation (≈261 mg kg −1 ) of long-chain alkanes C 30 –C 25 at each stage was obtained after instant Fenton pre-oxidation with K = 46. So up to 75% of the biodegradation of long-chain alkanes occurred after instant Fenton pre-oxidation with K = 46, which was 2.3- and 2.0-fold greater than the corresponding biodegradation of long-chain alkanes after noninstant Fenton pre-oxidation with K ≠ 46. CONCLUSION The study indicated that efficient sustainable bioremediation of long-chain alkanes can be achieved after instant Fenton pre-oxidation with K = 46. Analyses of microbial diversity revealed that a possible explanation for the efficient sustainable bioremediation of long-chain alkanes in soils was that sensitive, slow growth of the IHDs Nocardiode and Noviherbaspirillum was not damaged after instant Fenton pre-oxidation with K = 46. © 2019 Society of Chemical Industry
研究领域:
环境科学
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化学工程
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微生物学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Youwei Yang,Jianxing Wang,Yan Gao,Xuekun Tang,Chunying Wang,Xianping Luo
ZnFe 2 O 4 catalysts synthesized via hydrothermal (ZFO-H) and sol-gel (ZFO-S) methods were employed to activate peroxodisulfate (PDS) under UV light for the efficient conversion of low-concentration NH 4 + -N into environmentally benign N 2 , offering a promising solution for advanced wastewater treatment. Characterization revealed that the sol-gel-derived ZFO-S exhibited uniform agglomeration, smooth surfaces, and an 80% reduction in surface hydroxyl density (as indicated by the FTIR peak area at 3320 cm -1 ), outperforming both hydrothermally prepared and commercial ZnFe₂O₄ (ZFO-H and ZFO-M, respectively). This study addresses the critical challenge of ammonia nitrogen removal in wastewater, where conventional methods often struggle with low efficiency or secondary pollution. Mechanistic studies demonstrated that ZnFe 2 O 4 facilitated electron transfer at Zn sites to activate PDS, generating reactive species dominated by singlet oxygen ( 1 O 2 ), which drove NH 4 + -N oxidation. Density functional theory (DFT) calculations further elucidated the reaction pathway, highlighting preferential adsorption of NH 3 at oxygen sites on the ZnFe 2 O 4 (311) surface, followed by sequential dehydrogenation and coupling to form N 2 . Under optimal conditions (pH >9.25, 10 mM PDS, 25°C, 3 h), 97.40% of initial 50 mg/L NH₄ + -N was converted to N₂, with negligible NO 3 − byproduct formation (< 6%), demonstrating high feasibility for practical wastewater remediation. The reduced surface hydroxyl groups and lower work function of ZFO-S enhanced electron transfer, underscoring its superior catalytic activity. This work provides a novel strategy for designing hydroxyl-regulated photocatalysts tailored for wastewater treatment and advances the mechanistic understanding of persulfate-based ammonia nitrogen remediation in engineered water systems.
研究领域:
环境科学
·
催化化学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2025
·
IF 11.3
Jian Zhao,Qiaojuan Wang,Yangrui Huang,Shangbiao Fang,Gang Liu,Weixiao Qi,Yaohui Bai,Walter van der Meer,Jiuhui Qu,Huijuan Liu
Organic micropollutants (OMPs) facilitate the spread of antibiotic resistance genes (ARGs). Ammonia-oxidizing microorganisms (AOMs) are crucial for OMP degradation during riverbank filtration (RBF) and significantly influenced by NH4+-N concentrations. However, the effect of NH4+-N on OMP removal and ARG occurrence in RBF remains unclear. This study aimed to examine the effects of low (∼0.1 mg/L) and high (∼2.2 mg/L) NH4+-N concentrations on OMP removal, ARG occurrence, and microbial communities. NH4+-N addition had no significant effect on the removal of 108 out of 128 OMPs, suggesting that other factors primarily govern the removal process. Notably, NH4+-N addition enhanced the removal of 20 OMPs by 3–70%, including three quinolones (e.g., flumequine), indicating its promotion of specific OMP removals. This effect may primarily result from NH4+-N enhancing OMP biotransformation through the stimulation of AOMs (particularly AOA and comammox) and heterotrophs (e.g., Bradyrhizobium). Furthermore, NH4+-N addition significantly reduced the abundance of eight ARGs, including quinolone ARGs, likely due to its inhibition of antibiotic-resistant bacteria. Additionally, we hypothesize that NH4+-N alleviates OMP selective pressure on microorganisms by promoting OMP conversion through AOMs. This study enhances the understanding of microbe-mediated OMP removal in the presence of NH4+-N and its impact on ARG occurrence during RBF.
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产品关联
DOI
PubMed
高影响因子
Water
·
2025
·Vol. 17
·期 2
·179
·
IF 3
Wei Xu,Xiaoping Zhang,Guichang Zhang,Xin Zhang
The treatment of wastewater using microalgae is regarded as a green and potential technology. However, its engineering application has been largely hindered because of the limitation of microalgae separation and harvesting. Therefore, immobilization technology has been widely used to embed microalgae for wastewater treatment. In this paper, sodium alginate (SA) and polyvinyl alcohol (PVA) as the common immobilized carriers were used to immobilizeankistrodesmus falcatusfor simulated slaughtering wastewater (SSW) treatment. The experimental results of the mass transfer and adsorption of immobilized carriers were found to show that the mass transfer of SA-SiO2gel balls (SS-GB) was better than PVA-SA gel balls (PS-GB) and that the adsorption of PS-GB was better than SS-GB. When immobilizing microalgae with the two kinds of carriers, it was found that SA-SiO2microalgal spheres (SS-MS) were better than PVA-SA microalgal spheres (PS-MS) for the maintenance of microalgal cell activity and that PS-MS were better than SS-MS for the resistance to biodegradation. This is because the carrier of PS-MS had a thick shell and dense structure, while the carrier of SS-MS had a thin shell and loose structure. The results of SSW treatment by PS-MS and SS-MS were found to show that the total phosphorus (TP) removal rates of PS-MS and SS-MS were 90.31% and 86.60%, respectively. This indicates that the TP removal effect of PS-MS was superior to that of SS-MS. The adsorption kinetics simulation showed that the adsorption of TP onto PS-GB was controlled by chemisorption and that the adsorption of TP onto SS-GB was controlled by physical adsorption. The chemical oxygen demand (COD) and ammonium nitrogen (NH4+-N) removal of PS-MS were 9.30% and 10.70%, respectively, and the COD and NH4+-N removal of SS-MS were 54.60% and 62.08%, respectively. This indicates that the COD and NH4+-N removal effect of SS-MS were superior to PS-MS. This is the result of the combined action of the degradation by microalgal cells and adsorption by the carrier.
研究领域:
环境科学
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生物技术
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Wen-Jian Yang,Li-Hui Yang,Han-Jun Peng,Si-Hao Lv,Hafiz Muhammad Adeel Sharif,Wei Sun,Wei Li,Cao Yang,Hui Lin
Electroreduction removal of nitrate (NO 3 – -N) is considered as a promising approach to solve its adverse effects on environment and human health, where efficient and cheap catalysts are required. Perovskite-based catalysts showed a versatile catalytic ability for wide range of redox reactions, but seldom applied for NO 3 – -N reduction. Herein, four perovskite oxide cathodes, LaMO 3-δ (M = Fe, Co, Ni and Cu) were prepared and used for the reduction of NO 3 – -N. The Ruddlesden-Popper (RP) type La 2 CuO 4 exhibited the best NO 3 – -N catalytic activity among the four perovskite oxide cathodes, with a removal rate of 11.7 × 10 -3 min −1 . The high selectivity of NH 4 + -N (82.4 ± 2.2%) indicated that NH 4 + -N was the main final product for NO 3 – -N electroreduction at La 2 CuO 4 cathode, but 100% of N 2 selectivity could be obtained with addition of 1000 and 1500 mg/L Cl - as the electro-assisted chlorination process. The mechanism of NO 3 – -N electroreduction occurred by both electron- and H*-mediated pathway, and the oxygen vacancies and redox cycle of Cu(I)-Cu(II)-Cu(I) were proposed as the accommodation sties and direct electron sources for NO 3 – -N reduction. Generally, this study opens a novel avenue for the development of earth-abundant, cost-effective catalyst with effective NO 3 – -N electroreduction.
研究领域:
环境科学
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催化
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电化学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2021
·
IF 9.642
Yu Li,Jing Wang,Bingyan Li,Mengdan Geng,Yan Wang,Jianguo Zhao,Baodan Jin,Yanfei Li
The extracellular polymeric substances (EPS) and microbial community structures were investigated in wastewater treatment containing copper oxide nanoparticles (CuO NPs) (reactor R1) and CuO NPs and humic acid (HA) (reactor R2) using both sequencing batch bioreactors (SBRs), and their response on resistance genes expression was analyzed. The removal of influent chemical oxygen demands (COD) and NH 4 + -N was moderately influenced under CuO NPs (5 mg/L) stress, while the function of HA (10 mg/L) was not reflected. However, the EPS production and microbial community were affected by the HA addition. The expression of different antibiotic resistance genes (ARGs), metal-resistance genes (MRGs), and int I1 was related to the primary compositions of polysaccharides and proteins in EPS and different microbial communities at the genus level. Furthermore, the expression of resistance genes was not stimulated under CuO NPs stress, and supplying HA was suggested to reduce their expression in wastewater treatment.
研究领域:
环境科学
·
微生物学
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废水处理
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纳米技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）