作者机构:
[Li, Liuqin; Fang, Qi] School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China;[Zhu, Nengwu] School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, PR China;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China;[Huang, Xixian] School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China<&wdkj&>School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, PR China;[Ding, Yang] School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China
通讯机构:
[Yang Ding] S;School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China
摘要:
The dynamic reactions of uranium (U) with iron (Fe) minerals change its behaviors in soil environment, however, how the coexisted constituents in soil affect U sequestration and release on Fe minerals during the transformation remains unclear. Herein, coupled effects of lead (Pb) and dissolved organic matter (DOM) on U speciation and release kinetics during the catalytic transformations of ferrihydrite (Fh) by Fe(II) were investigated. Our results revealed that the coexistence of Pb and DOM significantly reduced U release and increased the immobilization of U during Fh transformation, which were attributed to the enhanced inhibition of Fh transformation, the declined release of DOM and the increased U(VI) reduction. Specifically, the presence of Pb increased the coprecipitation of condensed aromatics, polyphenols and phenols, and these molecules were preferentially maintained by Fe (oxyhydr)oxides. The sequestrated polyphenols and phenols could further facilitate U(VI) reduction to U(IV). Additionally, a higher Pb content in coprecipitates caused a slower U release, especially when DOM was present. Compared with Pb, the concentrations of the released U were significantly lower during the transformation. Our results contribute to predicting U sequestration and remediating U-contaminated soils.
通讯机构:
[Xixian Huang] S;[Dexin Ding] K;School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China
摘要:
Amorphous ferrihydrite (Fh) is abundant in aquatic environments and sediments, and often coprecipitates with dissolved organic matter (DOM) to form mineral-organic aggregates. The Fe(II)-catalyzed transformation of Fh to crystalline Fe (oxyhydr)oxides (e.g., goethite) can result in the changes of uranium (U) species, but the effects of DOM molecules on the sequestration and stability of U during Fe (oxyhydr)oxides transformation are poorly understood. In this study, the associations of DOM molecules with U during the coprecipitation of DOM with Fh were evaluated, and the effects of DOM molecules on the kinetics of U release during Fe (oxyhydr)oxides transformation were investigated using a combination of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), X-ray photoelectron spectroscopy (XPS), and kinetic experiments. FT-ICR-MS results indicated that, in addition to phenolic and polyphenolic compounds with higher O/C ratios, portions of phenolic compounds with lower O/C ratios and aliphatic compounds were also contributed to UO(2)(2+) binding when Fh coprecipitated with DOM. In comparison, phenolic and polyphenolic compounds with higher O/C ratios and condensed aromatics were preferentially retained on Fe (oxyhydr)oxides during the transformation. XPS results further suggested that the coprecipitated DOM molecules facilitated the reduction of U(VI) to U(IV) during the transformation, possibly through providing electrons or acting as electron shuttles. The kinetic experiment results indicated that the transformation processes accelerated U release from Fe (oxyhydr)oxides, but the coprecipitated DOM molecules slowed down U release. Our results contribute to understanding the behaviors of U and predicting the sequestration of U in the environment.
期刊:
Journal of Environmental Radioactivity,2023年265:107223 ISSN:0265-931X
作者机构:
[Yu, Ting; Xia, Ming; Liu, Shuyuan; Chen, Daijia] School of Resources Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China;Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 421001, China;[Yan, Zhiguo] The Fourth Research and Design Engineering Corporation, China National Nuclear Corporation, Shijiazhuang, 050021, China;[Ye, Yongjun] School of Resources Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China<&wdkj&>Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 421001, China
摘要:
Cavern is a place where workers often work in underground spaces, where radon is constantly released from surrounding rock surfaces. It is of great significance to develop effective ventilation to reduce radon in underground space for safe production and occupational health. For the purpose of controlling the radon concentration level in the cavern, the influence of upstream and downstream brattice length, upstream and downstream brattice to wall width on the volume average radon concentration and the plane average radon concentration at the height of the human respiratory zone (Z=1.6m) in the cavern, was studied by using the CFD (Computational fluid dynamics) method, and the operating parameters of ventilation induced by the brattice are optimized. The results show that the radon concentration in the cavern can be significantly reduced by using the brattice induced ventilation compared with no ventilation auxiliary facilities. This study provides a reference for local radon-reducing ventilation design of underground cavern.
摘要:
Phosphorus-rich biochar (PBC) has been extensively studied due to its significant adsorption effect on U(VI). However, the release of phosphorus from PBC into solution decreases its adsorption performance and reusability and causes phosphorus pollution of water. In this study, Alcaligenes faecalis (A. faecalis) was loaded on PBC to produce a novel biocomposite (A/PBC). After adsorption equilibrium, phosphorus released into solution from PBC was 2.32mg/L, while it decreased to 0.34mg/L from A/PBC (p<0.05). The U(VI) removal ratio of A/PBC reached nearly 100%, which is 13.08% higher than that of PBC (p<0.05), and it decreased only by 1.98% after 5 cycles. When preparing A/PBC, A. faecalis converted soluble phosphate into insoluble metaphosphate minerals and extracellular polymeric substances (EPS). And A. faecalis cells accumulated through these metabolites and formed biofilm attached to the PBC surface. The adsorption of metal cations on phosphate further contributed to phosphorus fixation in the biofilm. During U(VI) adsorption by A/PBC, A. faecalis synthesize EPS and metaphosphate minerals by using the internal components of PBC, thus increasing the abundance of acidic functional groups and promoting U(VI) adsorption. Hence, A/PBC can be a green and sustainable material for U(VI) removal from wastewater.
作者机构:
[Ding, Dexin; Zhang, Hui; Sheng, Liangbing; Ma, Jianhong] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China;[Sheng, Liangbing] Hunan Engineering Research Center for Monitoring and Treatment of Heavy Metal Pollution in the Upper Reaches of Xiangjiang River, Hengyang Normal University, Hengyang 421001, China;[Sheng, Liangbing] Hunan Province Key Laboratory of Green Development Technology for Extremely Low Grade Uranium Resources, Hengyang 421001, China;[Zhang, Hui; Ma, Jianhong] Hunan Province Key Laboratory of Green Development Technology for Extremely Low Grade Uranium Resources, Hengyang 421001, China;[Ding, Dexin] Hunan Province Key Laboratory of Green Development Technology for Extremely Low Grade Uranium Resources, Hengyang 421001, China. Electronic address: zh2015yl@163.com
通讯机构:
[Dexin Ding] K;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>Hunan Province Key Laboratory of Green Development Technology for Extremely Low Grade Uranium Resources, Hengyang 421001, China
关键词:
Acid in situ leach uranium mining;Slowly releasing phosphate;Uranium-contaminated groundwater
摘要:
Acid in-situ leach uranium mining significantly alters the geochemistry of the ore zone, and leaves uranium, residual acid, as well as other potential contaminants in groundwater, which bring harm to human health and ecological environment. Many investigators have been trying to propose remediation strategies for the uranium-contaminated groundwater. Phosphate is an effective immobilization reagent of uranium in the groundwater. However, direct injection of phosphate tends to quickly form precipitates, resulting in fast blockage of the seepage passages in the ore zone around the injection holes and hindering its diffusion. In this paper, HAP@SiO(2)-600, HAP@SiO(2)-600@25SA, and HAP@SiO(2)-600@75SA with core-shell structures were prepared. Their slow-release of phosphate, the effects of pH, contact time, initial uranium concentration, and coexisting ions on their removal rate and efficiency of uranium, and their function of remediating uranium-contaminated groundwater were investigated. It was found that the increase of SA content in the outer layer of HAP@SiO(2)-600@25SA and HAP@SiO(2)-600@75SA resulted in the slow release rate of phosphate, decreasing the removal rate of uranium. The adsorption capacities of HAP@SiO(2)-600, HAP@SiO(2)-600@25SA, and HAP@SiO(2)-600@75SA from the aqueous solution at pH=3.0 and 303K were up to 582.6, 558.5, and 507.3mgg(-1), respectively. In addition, the materials showed excellent uranium removal performance in experiments where multiple ions coexisted. For actual acidic uranium-contaminated groundwater, HAP@SiO(2)-600, HAP@SiO(2)-600@25SA, and HAP@SiO(2)-600@75SA effectively increased the pH from 2.75 to 4.40, 3.87, and 3.72, respectively, and decreased the uranium concentration from 5.12 to 0.0062, 0.0065, and 0.0058mgL(-1), respectively. The FT-IR, XRD, TEM and XPS characterizations were performed to further clarify the uranium removal mechanism, and it was found that the elimination of U(VI) was ascribed to dissolution-precipitation, adsorption and ion exchange. The results show that the core-shell composite material capable of slowly releasing phosphate is effective in remediating uranium-contaminated groundwater.
作者机构:
[Song, Dongping; Yang, Chunhai; Huang, Tao] Changshu Inst Technol, Sch Mat Engn, Suzhou 215500, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Changshu 215500, Peoples R China.;[Huang, Tao] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Jiangsu, Peoples R China.;[Zhang, Shu-wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
通讯机构:
[Tao Huang] S;School of Materials Engineering, Changshu Institute of Technology, 215500, China<&wdkj&>Suzhou Key Laboratory of Functional Ceramic Materials, Changshu Institute of Technology, Changshu, 215500, China<&wdkj&>School of Chemical Engineering & Technology, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China
期刊:
Environmental Science and Pollution Research,2022年29(1):1289-1300 ISSN:0944-1344
通讯作者:
Huang, T.;Du, J.
作者机构:
[Yu, Danni; Deng, Shihan; Liu, Longfei; Du, Jing; Huang, Tao] Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Jiangsu, Peoples R China.;[Zhang, Shuwen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Hunan, Peoples R China.
通讯机构:
[Tao Huang; Jing Du] S;School of Materials Engineering, Changshu Institute of Technology, Changshu, China<&wdkj&>School of Materials Engineering, Changshu Institute of Technology, Changshu, China
期刊:
Journal of Hazardous Materials,2022年424(Pt B):127441- ISSN:0304-3894
通讯作者:
Huang, Tao
作者机构:
[Song, Dongping; Li, Aiyin; Huang, Tao; Zhou, Lulu; Liu, Long-fei] Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Jiangsu, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Changshu 215500, Jiangsu, Peoples R China.;[Huang, Tao] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Jiangsu, Peoples R China.;[Tao, Hui] Chongqing Water Affairs Grp Co Ltd, 1 Longjiawan, Chongqing 400000, Peoples R China.;[Zhang, Shu-wen] Univ South China, Nucl Resources Engn Coll, Guangzhou 421001, Peoples R China.
通讯机构:
[Huang, Tao] C;Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Jiangsu, Peoples R China.
关键词:
*A dielectric barrier discharge configuration;*Binary equilibrium adsorption;*Contamination of Cs(+) and Sr(2+);*Non-thermal plasma;*Optimization;*Polyaluminum chloride
摘要:
The natural ecosystem will continually deteriorate for decades by the leakage of Cs and Sr isotopes. The exploration of the new materials or techniques for the efficient treatment of radioactive wastewater is critically important. In this study, a dielectric barrier discharge (DBD) configuration was constructed to operate the non-thermal plasma (NTP). The NTP was incorporated into the synthesis of polyaluminum chloride (PAC) in two different procedures to intensify the synthesis of PAC (NTP-PAC) and enhance the further removal of Cs and Sr from wastewater. The employment of NTP in two procedures both had significantly changed the physicochemical characteristics of PAC materials, which facilitated the further adsorption application of NTP-PAC on the treatment of Cs(+) and Sr(2+). Different molecular, morphological, and adsorption characteristics were confirmed to the NTP-PAC materials. The heterogeneous adsorption of the NTP-PAC can be appropriately fitted by both the pseudo-first-order kinetic model and the Elovich model. Both physisorption and chemisorption reaction mechanisms were ensured for the heterogeneous adsorption of the NTP-PAC material towards Cs(+) and Sr(2+), which guaranteed the excellent adsorption performance of NTP-PAC materials compared to PAC. The electron collisions caused by NTP with alum pulp created highly reactive growth precursors and intensified the nucleation and hydrolysis polymerization of PAC. The employment of NTP explicitly broadens the reaction pathways between PAC and cationic contaminants in the aqueous environment, which expands the application area of PAC materials in environmental sustainability.
通讯机构:
[Dexin Ding] K;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, People’s Republic of China<&wdkj&>School of Resource Environment and Safety Engineering, University of South China, Hengyang, People’s Republic of China
作者机构:
[Huang, Tao; Liu, Long-fei; Zhou, Lulu] Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Jiangsu, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Changshu 215500, Jiangsu, Peoples R China.;[Huang, Tao] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Jiangsu, Peoples R China.;[Zhang, Shu-wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
通讯机构:
[Huang, Tao] C;Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Jiangsu, Peoples R China.
关键词:
Green rust;Functionalized composite cementitious material;Geopolymer;Chromate;Granulated blast furnace slag;Fly ash
摘要:
Green rust functionalized geopolymer of composite cementitious materials (GR-CCM) was synthesized to improve the adsorption and subsequent stabilization/solidification of chromate in a holistic operating system. The initial pH in solution exhibited the most significant effect on the chromate removal by GR-CCM among three adsorption factors. The maximum monolayer adsorption capacity and theoretical saturation capacity of GR-CCM for Cr(VI) in the acidic condition were 55.01 mg/g and 41.70 mg/g, respectively. Amorphousness brought by loading GR weakened the crystallinity of composite cementitious materials (CCM), which enhanced the adsorption capacity of CCM and boosted the solidification process. The mixed-valent iron species in the GR-CCM not only directly engaged in the adsorption and reduction of chromate also positively strengthened the solidification of Cr species during the whole treatment. This study facilitates the application of GRs on the geopolymer materials and demonstrates the combination of adsorption and immobilization for the treatment of other potential heavy metal contamination. (C) 2020 Elsevier Ltd. All rights reserved.
摘要:
Biohazard performance of Sr radionuclide can be significantly magnified by its release from the contaminated sedimentation. In this study, hydroxyapatite nanoparticle-functionalized activated carbon electrode (AC-HAP) was synthesized and stacked to the cathode compartment of the electrokinetic (EK) system to develop a unipolar three-dimensional (3D) electrochemical process for Sr(2+) removal from spiked soils. Sr(2+) adsorption by AC-HAP can be fitted by the pseudo-first-order and pseudo-second-order kinetic models and the Langmuir, Freundlich, and Temkin isotherm models. The largest monolayer adsorption capacity of AC-HAP of 69.49mgg(-1) was evaluated in the pH range of 10-12 and at 40°C. 3D EK further intensified the adsorption process of AC-HAP and the corresponding Sr(2+) removal from aqueous environments. Voltage gradients and proposing time had a significant effect on the migration and transmission of Sr(2+) in the electrolyzer. The influence of competitive ions on Sr(2+) removal in the stock solutions followed Al(3+)<Mg(2+)<K(+)<Na(+)<Ca(2+) while followed Al(3+)<Na(+)<K(+)<Mg(2+)<Ca(2+) in 3D EK. The first three cycles for AC-HAP had taken roughly 50% of the reusability percentage. Sr(2+) removal from spiked samples in 3D EK was achieved by acid dissolution, electromigration, and selective uptake on particle electrode.
通讯机构:
[Song, Dongping] C;Changshu Inst Technol, Sch Chem & Mat Engn, 99,South 3rd Ring Rd, Changshu 215500, Jiangsu, Peoples R China.
关键词:
Green rust-coated expanded perlite;Microelectrode;Three-dimensional electrokinetics;Hexavalent chromium;Optimization;Breakthrough curve
摘要:
A green rust-coated expanded perlite (GR-coated Exp-p) microelectrode was synthesized and incorporated into a column-mode three-dimensional electrokinetic (3D-EK) platform to effectively pursue a continuous Cr(VI) removal from the aqueous solution. Brucite-like layers of GR were decorated onto the Exp-p material. The molar ratio of Fe(II) to Fe(III) played a most vital role among the three synthesis factors in influencing the performance of the particle electrode. For the equilibrium adsorption experiments, the target maximum adsorption capacity of 122mg/g was predicted by a target optimizer and desirability function at the conditions following the pH of 4.7, the initial concentration of 172.4mg/L, the dosage of 0.28g/L, and the temperature of 28.96°C, respectively. SO(4)(2-), Cl(-), and NO(3)(-) fiercely competed with Cr(VI) anions in the acidic conditions for the locally positive sites. A low concentration and a slow flow were favored in the column-mode 3D-EK platform. The pseudo-first-order and Langmuir models were suitable for describing the kinetics and isotherms of the adsorption process, respectively. Cr(VI) anions were electrostatically attracted to the silanol groups and GR surface of the adsorbent, subsequently reduced in both heterogeneity and homogeneity, and finally immobilized by coordinating with silanediol groups and silanetriol groups.
作者机构:
[Huang, Tao; Zhou, Lulu; Liu, Long-Fei] 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.;[Xie, Juan] Changshu Inst Technol, Sch Text Garment & Design, Changshu 215500, Peoples R China.;[Huang, Tao] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Peoples R China.;[Zhang, Shu-Wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
关键词:
Quadrivalent cerium;Laurylsulfonate green rust;Adsorption mechanism;Rare earth element;Synthesis optimization
摘要:
The layered laurylsulfonate intercalated green rust(lauryl-S GR) was synthesized to evaluate the influence of synthesis parameters and aqueous conditions on the adsorption of CeⅣ.The maximum adsorption capacity of 305.58 mg/g by lauryl-S GR was predictably obtained.The pseudo-first-order kinetic model was appropriate in fitting the whole uptake process in a weak acid environment.Three isotherm models including Langmuir, Freundlich, and Tempkin were all reliable in depicting the isotherm adsorption process.The maximum monolayer adsorption capacity of lauryl-S GR towards CeⅣ was 315.46 mg/g.Ce species including CeO and Ce2O3 besides CeO2 were matched in the XPS distribution, directly indicating the reduction reaction brought by FeⅡ in the GR occurred to hydrated CeⅣ ions during the adsorption.Nano-sized Ce particles attached to the lauryl-S GRs after the adsorption experiments were observed in the morphological characterization.Flocculated materials were formed on the surface of the lauryl-S GR at a pH of 7, which further reduced the active sites and disrupted the continuous uptake of CeⅣ to the lauryl-S GR.This study expands the application of GRs and supplies an ideal iron-based material for the construction of the affiliated recovery pathway to the traditional separation of Ce.
通讯机构:
[Ding, Dexin] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
关键词:
Uranium;Removal;Photoreduction;Wastewater
摘要:
Efficient elimination of U(VI) from uranium wastewater is an urgent task for sustainable nuclear energy and environmental protection. In this study, magnetic graphene oxide decorated graphitic carbon nitride (mGO/g-C3N4) nanocomposite was prepared and used for photocatalytic reduction of U(VI) in wastewater under visible LED light irradiation for the first time. The batch experiments indicated that the mGO/g-C3N4 (mGCN) nanocomposite could efficiently reduce U(VI) under visible LED light, and a high U(VI) extraction capacity of 2880.6 mg/g was obtained with an extraction efficiency of 96.02%. The transmission electron microscopy (TEM) elemental mapping, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses demonstrated that the soluble U(VI) was immobilized by transforming it to metastudtite ((UO2)O-2 center dot 2H(2)O) by mGCN nanocomposite under visible LED light irradiation. This work indicated that the mGCN is a promising visible light catalyst for treatment of uranium wastewater. (C) 2020 Elsevier Ltd. All rights reserved.