期刊:
Separation and Purification Technology,2025年354:129241 ISSN:1383-5866
通讯作者:
Zhongran Dai
作者机构:
[Zhongran Dai; Beichao Liang; Lijie Chen] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China;[Weilin Zhang] College of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, Hunan, China;[Yuan Gao] School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China;[Le Li] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>College of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, Hunan, China
通讯机构:
[Zhongran Dai] K;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China
摘要:
Photocatalysis holds promise for extracting uranium from aqueous solution. Nevertheless, conventional approaches generally rely on sacrificial agents and anaerobic conditions to maintain photocatalytic efficiency, which increases costs and causes secondary pollution. Herein, we introduce the design and synthesis of an S-scheme ZnIn2S4/g-C3N4 (ZISCN) heterojunction photocatalyst for the efficient removal of uranium via in-situ generating ZnIn2S4 on g-C3N4. Photoelectric characterization and theoretical calculation indicate that ZISCN boosts the absorption of visible light and promotes the effective separation and migration of charge carriers by forming an internal electric field (IEF) at the S-scheme heterojunction interface. This configuration integrates the strong reducing electrons of g-C3N4 and the potent oxidation holes of ZnIn2S4. Consequently, the as-synthesized ZISCN can efficiently remove uranium under an air atmosphere without the need for sacrificial agents and anaerobic conditions. The achieved U(VI) removal rate of 94.8 % surpasses that of ZnIn2S4 and g-C3N4 individually. Moreover, the photocatalytic extraction of U(VI) by ZISCN photocatalyst demonstrated excellent stability and anti-interference performance. After five cycles, the U(VI) removal rate remained above 85 %. Mechanism studies reveal that when electrons are generated by light in the ZISCN systems, they can reduce O2, leading to the formation of reactive species ·O2/H2O2. These species subsequently interact with U(VI), resulting in the precipitation of (UO2)O2·2H2O on the surface of ZISCN. This research provides valuable insights for the design of heterojunction photocatalysts for efficient, sacrificial agent-free uranium removal in ambient air environments.
摘要:
Uranium mining operations produce large volumes of acidic uranium mining wastewater, necessitating the development of environmentally friendly and recyclable materials for efficient uranium removal and recovery. The current study successfully produced hydroxyapatite (HAP-L) and magnetic phosphate composites (CaFeP-1, CaFeP-2, and FePO4) through a combination of mixing, ultrasonication, hydrothermal precipitation, and calcination methods. The research explores the influence of various parameters such as pH, solid-liquid ratio, contact time, initial uranium concentration, co-existing ions, and recyclability on the uranium removal efficiency of these materials. The findings indicate exceptional uranium adsorption capacities, with CaFeP-1 exhibiting the highest capacity among the materials, especially in acidic environments. Moreover, CaFeP-1 displays strong resistance to interference from other ions and can be recycled multiple times while maintaining high removal rates. Treatment of acidic uranium mining wastewater by CaFeP-1 results in pH adjustment and the reduction of uranium and other ion concentrations, making it a promising solution for comprehensive remediation of acidic uranium mining wastewater. The U(VI) removal mechanism by CaFeP-1 was validated through XRD, FT-IR, and XPS results. The U(VI) removal was attributed to processes such as dissolution-precipitation, surface complexation, and ion exchange. The formation of sodium uranyl phosphate hydrate was identified as a new product following U(VI) abatement by CaFeP-1. In summary, CaFeP-1 shows great potential for the effective treatment of acidic uranium mining wastewater.
期刊:
Journal of Hazardous Materials,2024年476:134975 ISSN:0304-3894
通讯作者:
Huang Yu
作者机构:
[Ding, Dexin; Yang, Zhaolan; Xiong, Rui; Lv, Wenpan; Hu, Nan; Tan, Wenfa; Xiao, Fangfang] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China;[Yan, Qingyun; Zhang, Dandan; He, Zhili] Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Marine Science, State Key Laboratory for Biocontrol, Sun Yat-sen University, Zhuhai 519080, China;[Hu, Ruiwen] Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA;[Yu, Huang] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China. Electronic address: yuhuang@usc.edu.cn
通讯机构:
[Huang Yu] K;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China
摘要:
Phosphate-solubilizing bacteria (PSB) are important but often overlooked regulators of uranium (U) cycling in soil. However, the impact of PSB on uranate fixation coupled with the decomposition of recalcitrant phosphorus (P) in mining land remains poorly understood. Here, we combined gene amplicon sequencing, metagenome and metatranscriptome sequencing analysis and strain isolation to explore the effects of PSB on the stabilization of uranate and P availability in U mining areas. We found that the content of available phosphorus (AP), carbonate-U and Fe-Mn-U oxides in tailings was significantly (P<0.05) higher than their adjacent soils. Also, organic phosphate mineralizing (PhoD) bacteria (e.g., Streptomyces) and inorganic phosphate solubilizing (gcd) bacteria (e.g., Rhodococcus) were enriched in tailings and soils, but only organic phosphate mineralizing-bacteria substantially contributed to the AP. Notably, most genes involved in organophosphorus mineralization and uranate resistance were widely present in tailings rather than soil. Comparative genomics analyses supported that organophosphorus mineralizing-Streptomyces species could increase soil AP content and immobilize U(VI) through organophosphorus mineralization (e.g., PhoD, ugpBAEC) and U resistance related genes (e.g., petA). We further demonstrated that the isolated Streptomyces sp. PSBY1 could enhance the U(VI) immobilization mediated by the NADH-dependent ubiquinol-cytochrome c reductase (petA) through decomposing organophosphorous compounds. This study advances our understanding of the roles of PSB in regulating the fixation of uranate and P availability in U tailings.
摘要:
This study investigates the effects of nitrate exposure on the indigenous consortium mediated remediation of uranium-contaminated groundwater. Intermittent experiments reveal that high-nitrate concentrations hinder uranium reduction, whereas using glycerophosphate as carbon source, microbe could immobilize uranium by generating biomineralized precipitates with high crystallinity, and these precipitates exhibited better stability at high-nitrate concentration compared to those formed at low-nitrate condition. We also elucidated the mechanism of uranium removal by microorganisms under different conditions by analyzing changes in solution chemistry, products formed and microbial community structures. This work extends the scope for treating uranium-contaminated groundwater and is important for achieving long-term treatment of uranium contamination.
关键词:
Efflux pumps;Heavy metal resistance;Secretome
摘要:
Heavy metal-resistant bacteria secrete extracellular proteins (e-PNs). However, the role of e-PNs in heavy metal resistance remains elusive. Here Fourier Transform Infrared Spectroscopy implied that N-H, C=O and NH(2)-R played a crucial role in the adsorption and resistance of Ni(2+) in the model organism Cuprividus pauculus 1490 (C. pauculus). Proteinase K treatment reduced Ni(2+) resistance of C. pauculus underlining the essential role of e-PNs. Further three-dimension excitation-emission matrix fluorescence spectroscopy analysis demonstrated that tryptophan proteins as part of the e-PNs increased significantly with Ni(2+) treatment. Proteomic and quantitative real-time polymerase chain reaction data indicated that major changes were induced in the metabolism of C. pauculus in response to Ni(2+). Among those lipopolysaccharide biosynthesis, general secretion pathways, Ni(2+)-affiliated transporters and multidrug efflux play an essential role in Ni(2+) resistance. Altogether the results provide a conceptual model for comprehending how e-PNs contribute to bacterial resistance and adsorption of Ni(2+).
作者机构:
[Feng, Yu-Xuan; Huang, Tao] Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Changshu 215500, Peoples R China.;[Zhou, Lulu] Changzhou Univ, Sch Environm & Safety Engn, 1 Gehu Rd, Changzhou 213164, Peoples R China.;[Zhang, Shu-wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
通讯机构:
[Huang, T ] C;Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Peoples R China.
关键词:
Self-cementation;Arsenic-contaminated soil;Binary (hydro)oxides of polyvalent ferromanganese;Alkali-composite activation;Geopolymerization kinetics;Geopolymerization kinetics
摘要:
The self-cementation characteristics of arsenic (As)-contaminated soil were comprehensively investigated in this study. Different non-thermal plasma-irradiated binary (hydro)oxides of polyvalent ferromanganese (poly-Fe-Mn) were synthesized and exploratorily dispersed to soil samples to activate solidification and stabilization during the self-cemented process. The maximum compressive strength of 56.35 MPa and the lowest leaching toxicity of 0.004 mg/L were obtained in the proof test under optimal conditions (i.e., the mass ratio of the poly-Fe-Mn to the soil sample of 0.05; the mass ratio of the composite alkali activator (NaOH + CaO) to the soil sample of 0.25; the mass ratio of CaO to NaOH of 1.5; the mass ratio of the DI water to the binder of 0.515). The composite alkaline activator primarily contributed to the strength formation of the self-cemented matrix while the poly-Fe-Mn significantly influenced the reduction of the As-leaching toxicities. The poly-Fe-Mn maintained diffusion-controlled polycondensation and strengthened the nucleation process during self-cementation. The amount of water and the dosage of poly-Fe-Mn caused an interactive influence on the self-cemented solidification of contaminated soils. The solidified samples with poly-Fe-Mn exhibited better thermal decomposition than their counterparts, reflecting the enhancement of poly-Fe-Mn to the matrix. Some minerals including C-S-H, kaolinite, gehlenite, diopside sodian, augite, and albite were matched in the samples, directly demonstrating the geopolymerization-steered self-cementation of the As soil. The employment of poly-Fe-Mn not only reinforced the immobilization of As pollutants in the matrix but also induced the self-cementation of soils by intensifying the composite alkaline-activated geopolymerization kinetics.
摘要:
U(VI) and tetracycline (TC) in hospital wastewater pose serious threats to human health and the environment. In this study, agricultural corn straw residue was utilized as a precursor for biochar, and biochar-supported nanohydroxyapatite (nHAP) adsorbents (CSPCs) were synthesized at various ratios. These CSPCs were employed for the removal of U(VI) and TC in both one -component and two -component systems. In the one -component system, the adsorption capacity of the material was related to the ratio of nHAP to biomass, and the maximum adsorption capacities of CSPC-1 (nHAP/biomass = 1/1) for U(VI) and TC were 724.63 mg g(-1) and 15.06 mg g(-1), respectively. The XPS and XRD results confirmed that biochar promoted the dissolution and precipitation of U(VI) by nHAP, which stabilized the adsorption of U(VI) by CSPC-1. In the two -component system, the complexation strength of U(VI) and TC had a significant effect on the adsorption of both. At pH < 3.0, U(VI) inhibited the adsorption of TC, whereas TC enhanced the adsorption of U(VI). However, at pH > 4.0, the adsorption of U(VI) and TC were mutually reinforcing. At pH = 5.0, TC inhibited the adsorption of U(VI) only when the concentration of TC was significantly greater than that of U(VI). Combined with the systematic analysis of the FTIR, XPS and Raman spectroscopic results, these results suggest that these phenomena can be attributed to the complexation-bridging interactions between U(VI) and TC and their competition for adsorption sites.
摘要:
To investigate the strengthening effects and mechanisms of bioaugmentation on the microbial remediation of uranium-contaminated groundwater via bioreduction coupled to biomineralization, two exogenous microbial consortia with reducing and phosphate-solubilizing functions were screened and added to uranium-contaminated groundwater as the experimental groups (group B, reducing consortium added; group C, phosphate-solubilizing consortium added). β-glycerophosphate (GP) was selected to stimulate the microbial community as the sole electron donor and phosphorus source. The results showed that bioaugmentation accelerated the consumption of GP and the proliferation of key functional microbes in groups B and C. In group B, Dysgonomonas, Clostridium_sensu_stricto_11 and Clostridium_sensu_stricto_13 were the main reducing bacteria, and Paenibacillus was the main phosphate-solubilizing bacteria. In group C, the microorganisms that solubilized phosphate were mainly unclassified_f_Enterobacteriaceae. Additionally, bioaugmentation promoted the formation of unattached precipitates and alleviated the inhibitory effect of cell surface precipitation on microbial metabolism. As a result, the formation rate of U-phosphate precipitates and the removal rates of aqueous U(VI) in both groups B and C were elevated significantly after bioaugmentation. The U(VI) removal rate was poor in the control group (group A, with only an indigenous consortium). Propionispora, Sporomusa and Clostridium_sensu_stricto_11 may have played an important role in the removal of uranium in group A. Furthermore, the addition of a reducing consortium promoted the reduction of U(VI) to U(IV), and immobilized uranium existed in the form of U(IV)-phosphate and U(VI)-phosphate precipitates in group B. In contrast, U was present mainly as U(VI)-phosphate precipitates in groups A and C. Overall, bioaugmentation with an exogenous consortium resulted in the rapid removal of uranium from groundwater and the formation of U-phosphate minerals and served as an effective strategy for improving the treatment of uranium-contaminated groundwater in situ.
作者机构:
[Liu, Shu Yuan; Ding, Ku Ke] Chinese Ctr Dis Control & Prevent, Natl Inst Radiol Protect, Beijing 100088, Peoples R China.;[Zhang, Li; Ding, Ku Ke] Chinese Ctr Dis Control & Prevent, Off Publ Hlth Management, Beijing 102206, Peoples R China.;[Ye, Yong Jun] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Min, Hengyang 421001, Hunan, Peoples R China.
通讯机构:
[Ding, KK ] C;Chinese Ctr Dis Control & Prevent, Natl Inst Radiol Protect, Beijing 100088, Peoples R China.;Chinese Ctr Dis Control & Prevent, Off Publ Hlth Management, Beijing 102206, Peoples R China.
摘要:
Objective This study aimed to efficiently reduce the release of radon from water bodies to protect the environment. Methods Based on the sizes of the experimental setup and modular float, computational fluid dynamics (CFD) was used to assess the impact of the area coverage rate, immersion depth, diffusion coefficient, and radon transfer velocity at the gas-liquid interface on radon migration and exhalation of radon-containing water. Based on the numerical simulation results, an estimation model for the radon retardation rate was constructed. The effectiveness of the CFD simulation was evaluated by comparing the experimental and simulated variation values of the radon retardation rate with the coverage area rates. Results The effect of radon transfer velocity on radon retardation in water bodies was minor and insignificant according to the appropriate value; therefore, an estimation model of the radon retardation rate of the coverage of a radon-containing water body was constructed using the synergistic impacts of three factors: area coverage rate, immersion depth, and diffusion coefficient. The deviation between the experimental and simulated results was < 4.3%. Conclusion Based on the numerical simulation conditions, an estimation model of the radon retardation rate of covering floats in water bodies under the synergistic effect of multiple factors was obtained, which provides a reference for designing covering floats for radon retardation in radoncontaining water.
通讯机构:
[Yan, QY ] S;Sun Yat Sen Univ, Sch Environm Sci & Engn, Southern Marine Sci & Engn Guangdong Lab Zhuhai, State Key Lab Biocontrol,Sch Ecol,Guangdong Prov O, Guangzhou 510006, Peoples R China.
关键词:
Metabolic pathway;Metagenomic analysis;Microbial coupling;Nitrogen and sulfur cycling
摘要:
Microorganisms play important roles in the biogeochemical cycles of lake sediment. However, the integrated metabolic mechanisms governing nitrogen (N) and sulfur (S) cycling in eutrophic lakes remain poorly understood. Here, metagenomic analysis of field and bioreactor enriched sediment samples from a typical eutrophic lake were applied to elucidate the metabolic coupling of N and S cycling. Our results showed significant diverse genes involved in the pathways of dissimilatory sulfur metabolism, denitrification and dissimilatory nitrate reduction to ammonium (DNRA). The N and S associated functional genes and microbial groups generally showed significant correlation with the concentrations of NH(4)(+), NO(2)(-) and SO(4)(2), while with relatively low effects from other environmental factors. The gene-based co-occurrence network indicated clear cooperative interactions between N and S cycling in the sediment. Additionally, our analysis identified key metabolic processes, including the coupled dissimilatory sulfur oxidation (DSO) and DNRA as well as the association of thiosulfate oxidation complex (SOX systems) with denitrification pathway. However, the enriched N removal microorganisms in the bioreactor ecosystem demonstrated an additional electron donor, incorporating both the SOX systems and DSO processes. Metagenome-assembled genomes-based ecological model indicated that carbohydrate metabolism is the key linking factor for the coupling of N and S cycling. Our findings uncover the coupling mechanisms of microbial N and S metabolism, involving both inorganic and organic respiration pathways in lake sediment. This study will enhance our understanding of coupled biogeochemical cycles in lake ecosystems.
摘要:
The radiation dose of workers in underground uranium mines mainly comes from radon and radon progeny. To ensure a healthy and safe work environment, it is necessary and urgent to optimize the design of ventilation systems. As such, based on the simplified radon diffusion-advection migration model of the rocks, this paper proposes 1) two methods for determining the radon exhalation rate modified by pressure drop, 2) three methods for calculating radon activity concentration of single-branch, and 3) the novel adjustment algorithm and solving procedures for calculating and adjusting the radon activity concentration in ventilation networks by modifying the radon exhalation rate, demonstrated on a specific ventilation network in a simulated underground uranium mine with calculation and analysis via MATLAB. The results show that 1) the radon exhalation rate of different branches can be modified by their pressure drop, and 2) the proposed method can be used to reveal the influences of different ventilation methods and fan pressures on the radon activity concentration in the ventilation network and the radon release rate to the atmosphere.
摘要:
Small-scale measurements of the radon exhalation rate using the flow-through and closed-loop methods were conducted on the surface of a uranium tailing pond to better understand the differences between the two methods. An abnormal radon exhalation behavior was observed, leading to computational fluid dynamics (CFD)-based simulations in which dynamic radon migration in a porous medium and accumulation chamber was considered. Based on the in-situ experimental and numerical simulation results, variations in the radon exhalation rate subject to permeability, flow rate, and insertion depth were quantified and analyzed. The in-situ radon exhalation rates measured using the flow-through method were higher than those measured using the closed-loop method, which could be explained by the negative pressure difference between the inside and outside of the chamber during the measurements. The consistency of the variations in the radon exhalation rate between the experiments and simulations suggests the reliability of CFD-based techniques in obtaining the dynamic evolution of transient radon exhalation rates for diffusion and convection at the porous medium-air interface. The synergistic effects of the three factors (insertion depth, flow rate, and permeability) on the negative pressure difference and measured exhalation rate were quantified, and multivariate regression models were established, with positive correlations in most cases; the exhalation rate decreased with increasing insertion depth at a permeability of 1 x 10-11 m2. CFD-based simulations can provide theoretical guidance for improving the flow-through method and thus achieve accurate measurements.
摘要:
An in vivo model is necessary for toxicology. This review analyzed the uses of zebrafish (Danio rerio) in toxicology based on bibliometrics. Totally 56,816 publications about zebrafish from 2002 to 2023 were found in Web of Science Core Collection, with Toxicology as the top 6 among all disciplines. Accordingly, the bibliometric map reveals that "toxicity" has become a hot keyword. It further reveals that the most common exposure types include acute, chronic, and combined exposure. The toxicological effects include behavioral, intestinal, cardiovascular, hepatic, endocrine toxicity, neurotoxicity, immunotoxicity, genotoxicity, and reproductive and transgenerational toxicity. The mechanisms include oxidative stress, inflammation, autophagy, and dysbiosis of gut microbiota. The toxicants commonly evaluated by using zebrafish model include nanomaterials, arsenic, metals, bisphenol, and dioxin. Overall, zebrafish provide a unique and well-accepted model to investigate the toxicological effects and mechanisms. We also discussed the possible ways to address some of the limitations of zebrafish model, such as the combination of human organoids to avoid species differences.
通讯机构:
[Yang, JH ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
关键词:
Fe/Bi2CuO4-PVAC;Photocatalysis-Fenton;Amorphous iron oxide;Catalyst stability;Organic dyes
摘要:
The research and application of bismuth-based semiconductor photocatalysis for the green and environmentally friendly degradation of dye pollutants have garnered widespread attention from scholars. The key factor in photocatalytic activity lies in the development of composite catalysts with high activity and high stability. A new type of Fe/Bi2CuO4-PVAC photocatalyst (FBC) was constructed by low-temperature calcination, which can effectively avoid serious iron leaching problems. Under the photocatalytic Fenton system, the composite material FBC exhibits high-performance degradation of various organic pollutants such as methyl orange (MO), tetracycline (TC), Rhodamine B (RhB), and methyl blue (MB), and the optimal removal rates were 98.67%, 97.90%, 91.50% and 96.32%, respectively. The structure, morphology, optics, and electronic properties were systematically characterized. Finally, A possible photocatalytic mechanism of FBC composite materials was proposed in the photo-Fenton catalysis reasonably, suggesting that the main reactive oxygen species (ROS) is center dot OH in the photo-Fenton degradation of composite catalysts, rather than center dot O2- generated in the Bi2CuO4 photocatalysis. The high performance mainly stems from the synergistic effect between photo-induced charge carrier separation and the interface Fenton-like reaction between iron oxide and H2O2. In addition, the excellent degradation performance and chemical stability provide the possibility for practical potential applications.
摘要:
The recruitment of microorganisms by plants can enhance their adaptability to environmental stressors, but how root-associated niches recruit specific microorganisms for adapting to metalloid-metal contamination is not well-understood. This study investigated the generational recruitment of microorganisms in different root niches of Vetiveria zizanioides (V. zizanioides) under arsenic (As) and antimony (Sb) stress. The V. zizanioides was cultivated in As- and Sb-cocontaminated mine soils (MS) and artificial pollution soils (PS) over two generations in controlled conditions. The root-associated microbial communities were analyzed through 16S rRNA, arsC, and aioA gene amplicon and metagenomics sequencing. V. zizanioides accumulated higher As(III) and Sb(III) in its endosphere in MS in the second generation, while its physiological indices in MS were better than those observed in PS. SourceTracker analysis revealed that V. zizanioides in MS recruited As(V)- and Sb(V)-reducing microorganisms (e.g., Sphingomonales and Rhodospirillaceae) into the rhizoplane and endosphere. Metagenomics analysis further confirmed that these recruited microorganisms carrying genes encoding arsenate reductases with diverse carbohydrate degradation abilities were enriched in the rhizoplane and endosphere, suggesting their potential to reduce As(V) and Sb(V) and to decompose root exudates (e.g., xylan and starch). These findings reveal that V. zizanioides selectively recruits As- and Sb-reducing microorganisms to mitigate As-Sb cocontamination during the generational growth, providing insights into novel strategies for enhancing phytoremediation of metalloid-metal contaminants.