MINERALS ENGINEERING
·
2024
·
IF 4.9
Guihong Han,Aohua Li,Yizhuang Wang,Hu Sun,Yanfang Huang,Bingbing Liu
The mining of strategic U-Mo deposits invariably leads to the generation of wastewater with significant risks of radioactive and heavy metal pollution. This study explores a novel process for the simultaneous precipitation-adsorption of U and Mo from mine drainage, with subsequent solidification of the radioactive Fe(OH) 3 sediments using tailings. The results demonstrate that, under specific conditions, such as 33.6 mg/L Fe 3+ and pH 6.0–7.0, more than 97 % of U and Mo can be efficiently co-removed, and the treated water exhibits a gross α radioactivity of less than 0.2 Bq/L. The U-bearing Fe(OH) 3 sediments are transformed into general solid wastes, exhibiting low α radioactivity of less than 1.0 Bq/kg for 238 U, 232 Th or 226 Ra, after being blended with tailings in a mass ratio of 1:50. The reaction, adsorption and solidification mechanisms are further elucidated. The U and Mo are primarily precipitated and adsorbed in the forms of UO 2 (OH) 2 and Fe 2 (MoO 4 ) 3 respectively. The U-bearing Fe(OH) 3 particles are firmly encapsulated by negatively charged particles of phlogopite, quartz, and orthoclase, and agglomerate into large particles within the solidification product, thereby reducing U dissolution in simulated acid rain. Ultimately, a sustainable treatment flowsheet is established for the management of U-Mo ore mine drainage and tailings.
研究领域:
环境科学
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放射化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Penggang Li,Ping Zhang,Aishu Li,Lin Yu,Mengying Si,Qi Liao,Zhihui Yang,Weichun Yang
Understanding the formation of uranyl-arsenate compounds (M(UO 2 ) 2 (AsO 4 ) 2 ·nH 2 O, M represents divalent metallic cations) is of great importance in controlling the mobility and fate of uranium (U) and arsenic (As) in the natural environment. Phosphate is a ubiquitous coexisting ion with properties similar to arsenate and can complex with uranyl to form uranyl phosphate compounds, thus potentially affecting the formation of uranyl-arsenate compounds. Herein, the effect of phosphate, on the immobilization of uranyl, arsenate and divalent metallic cations (e.g., Fe 2+ , Mg 2+ , Ni 2+ , Cu 2+ ) was explored. Surprisingly, the presence of phosphate promoted the immobilization of uranyl arsenate with the divalent metallic cations under acidic conditions. For example, at pH 3.0, the immobilization efficiency of uranyl and arsenate in the uranyl-arsenate-Fe 2+ system increased from 20.6 % and 18.6 % to 82.6 % and 52.2 %, respectively. Moreover, the chemical stability of the formed uranyl arsenate-bearing compounds in the presence of phosphate is significantly improved, and the TCLP leachability of As and U decreased by 81 % and 97 %, respectively. The experimental results illustrated that with PO 4 3- served as a proton acceptor, uranyl and arsenate species were changed and more metallic cations participate in immobilization. Gibbs free energy and Gibbs free energies change also illustrated that the formation of Fe(UO 2 ) 2 (AsO 4 ) 2 ·5H 2 O was relatively thermodynamically favorable in the presence of phosphate. The results of thermodynamic calculations could account for the enhancement effects of phosphate on immobilization of uranyl arsenate. The findings have important implications for the mobility and fate of U and As and the solution of their co-contamination, especially in acidic environments.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
·
2025
·Vol. 122
·期 12
·e2501354122
·
IF 9.1
Leiming Lin,Zheng Li,Jun Ren,Ying Meng,Fubo Luan
The co-occurrence of arsenic and uranium in groundwater has been found in many countries, posing a significant challenge to human health. Here, we have demonstrated the efficient simultaneous removal of arsenic and uranyl-carbonate complexes from groundwater using {001}-TiO2. Surprisingly, the presence of U(VI) greatly enhanced the adsorption of As(V) on {001}-TiO2, while As(V) had a negligible impact on U(VI) adsorption. Through in situ ATR-FTIR spectroscopy, we uncovered a mechanism involving the formation of a ternary surface complex [Ti–U(VI)–As(V)] on the surface of {001}-TiO2. This ternary surface complex formed through the substitution of CO32- from uranyl coordination sites. Furthermore, the adsorbed As(V) and U(VI) can be easily recovered using a sodium hydroxide solution, and {001}-TiO2 can be used repeatedly. Our findings offer a promising solution for the simultaneous removal of As(V) and U(VI) from groundwater and provide valuable insights into the mechanisms involved in their removal.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Shuaichuan Cui,Xingxing Wang,Yifan Huang,Shihan Liu,Ziming Li,Yifan Zhang,Shusen Chen,Pengyang Deng
Herein, a defect-rich UiO-66-NH 2 hybrid membrane (DUUM) was successfully synthesized via in-situ growth of defective UiO-66-NH 2 onto irradiation-treated ultra-high molecular weight polyethylene fabrics to enhance the uranium extraction from seawater. The concentration of lattice defects within the framework is regulated by simply adjusting the ratio of ligand to metal (L/M), and DUUM with the L/M ratio of 1 exhibits the best uranium adsorption capacity. The adsorption kinetics investigation shows that DUUM has a higher adsorption rate than UiO-66-NH 2 powders, and the adsorption isotherms investigation shows DUUM has a saturated uranium adsorption capacity of 460 mg·g −1 which is about 5 times that of the defective UiO-66-NH 2 powders. DUUM exhibits a flux of 1440 LMH and a uranium removal efficiency of 65.5 % from natural seawater through single-pass filtration. More importantly, DUUM demonstrates excellent stability in real seawater environments (40-day) and under high doses of gamma-ray irradiation (300 kGy). The enhanced adsorption capacity is attributed to the membrane structure of DUUM which enhances exchange efficiency at the interface between uranium and DUUM via filtration, and the lattice defects which increase the specific surface area and expose more adsorption sites. The high stability results from the inherent hydrophobicity and radiation crosslinking features of the UP substrates. This study about DUUM will promote the practical application of efficient MOF membrane in fast uranium extraction from real seawater, as well as nuclear wastewater.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CLAY SCIENCE
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2021
·
IF 5.467
Baihui Zhai,Shan Zhu,Qiang Tian,Na Li,Minhao Yan,Mark J. Henderson
The present study concerns the removal of thorium and uranium from aqueous solution, and particularly the effect of clay particle size and morphology on the adsorption of polynuclear actinide complexes by synthetic saponite nanoscale powders. Saponites were synthesized from a reactant mixture containing aluminum nitrate, magnesium nitrate, and either sodium silicate or sodium germanate . The saponite powders were analyzed by TEM , XRD , SAXS , N 2 -adsorption-desorption isotherms and FT-IR. Ge-saponite contained randomly stacked platelets ≈ 100 nm long and 80 nm wide, while Si-saponite showed roughly spherical agglomerates ≈ 60–80 nm in size. Small-angle X-ray scattering measurements indicated a hierarchical pore network among the plates and their agglomerates. Thorium polymers composed of fractal aggregates of branched filaments were characterized by synchrotron radiation-SAXS. The distribution coefficient ( K d mL/g) values for thorium (20 μg/mL) at pH 4 were: Ge-saponite (10 5 ) ≈ Si-saponite (10 5 ) > raw saponite (10 4 ) ≈ raw saponite (washed) (10 4 ). The K d values for uranium (20 μg/mL) at pH 5.5 were: Ge-saponite (10 3 ) ≈ raw saponite (washed) (10 3 ) ≈ Si-saponite (10 3 ) ≈ raw saponite (10 3 ). The difference in uranyl adsorption performance observed between the two nanoparticle forms of saponite was attributed to a larger pore width for Ge-saponite (3.5 nm) compared with Si-saponite (0.8 nm). The results have implications for mineral ore tailings containing thorium(IV) and, by analogy, Pu(IV) in a clay buffer environment within a geological repository for high-level nuclear waste .
研究领域:
环境科学
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放射化学
✓ 已验证
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2024
·Vol. 50
·期 6
·2897-2915
·
IF 2.8
Liu Zengcheng,Wang Zhongchao,Wang Yanfei
The phosphinimide materials described in this paper were synthesized by polymerization precipitation. The properties of complexes coordinated with metal ions can be used as adsorbents for the adsorption of radioactive elements by using ligands such as imide and phosphorus groups. Then, the synthetic phosphinimide was characterized in detail by FT-IR, SEM, EDS and XPS, and its morphology and structural changes were studied. In addition, the effects of the material on the removal of uranium(VI) from aqueous solutions at different pH, sorbent doses, contact times, initial concentrations, and temperatures were studied. The experimental data shows that the adsorption process can fit the pseudo-second-order kinetic model well, which is in line with the Langmuir isotherm model. The thermodynamic study of adsorption shows that the adsorption process is a spontaneous endothermic process. In addition, at a temperature of 303.15 K and pH = 6, the maximum adsorption of uranium(VI) by phosphinimide in 25 min can reach 234.6 mg g −1 , and a removal rate of 97.75%.
研究领域:
化学
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2018
·
IF 3.12
Qingyuan Hu,Yuling Zhu,Baowei Hu,Songhua Lu,Guodong Sheng
The magnetic iron oxide (Fe 3 O 4 ) nanoparticles stabilized on the biochar were synthesized by fast pyrolysis of Fe(II)-loaded hydrophyte biomass under N 2 conditions. The batch experiments showed that magnetic biochar presented a large removal capacity (54.35 mg/g) at pH 3.0 and 293 K. The reductive co-precipitation of U(VI) to U(IV) by magnetic biochar was demonstrated according to X-ray diffraction, X-ray photoelectron spectroscopy and X-ray absorption near edge structure analysis. According to extended X-ray absorption fine structure analysis, the occurrence of U-Fe and U-U shells indicated that high effective removal of uranium was primarily inner-sphere coordination and then reductive co-precipitation at low pH. These observations provided the further understanding of uranium removal by magnetic materials in environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER AIR AND SOIL POLLUTION
·
2018
·Vol. 229
·期 4
·1-10
·
IF 1.769
Dai Ying,Lv Riwen,Huang Dejuan,Tao Qinqin
Humic acid (HA) plays an important role in the migration and transformation of uranium in natural waters. To effectively remove uranium in the presence of HA, a bifunctional polymer, diethylenetriaminepentaacetic acid cross-linked β -cyclodextrin (DTPA- β -CD), was synthesized by polycondensation reaction. The sorption performance of DTPA- β -CD in functions of pH, ionic strength, contact time, initial time, and temperature were explored batch wise. Experimental results showed that DTPA- β -CD could concurrently sorb uranium and HA around pH of 3.0. The sorption strongly depended on pH and on ionic strength, demonstrating outer-sphere surface complex in nature. Two sorption kinetics well followed pseudo-second-order model. Sorption isotherm accorded with Sips model. Increasing temperature facilitated uranium and restrained HA sorption. This work demonstrated that DTPA- β -CD was a promising material for sorbing uranium in the presence of HA.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2018
·
IF 2.196
Hao Lei,Ning Pan,Xiaoqiang Wang,Hao Zou
A novel phytic acid impregnated polyaniline (PA-PANI) was synthesized by a in situ polymerization and supermolecular self-assembly method and has been used as an adsorbent for efficient capture of U(VI) from aqueous solution. The structure and morphology of the adsorbent were well characterized. The influence of different factors such as pH value, ionic strength, contact time, initial U(VI) concentration and temperature on the adsorption of U(VI) onto PA-PANI-3 were carried out by batch adsorption experiments. The results demonstrated an enhanced U(VI) adsorption capacity of 86.6 mg/g for PA-PANI-3, greatly exceeding that of polyaniline (PANI, 8.8 mg/g). The adsorption process follows the pseudo-second-order kinetic and Langmuir isotherm models with the theoretical maximum adsorption capacity of 90.3 mg/g. According to the calculation from the Dubinin–Radushkevich isotherm model equation, it is suggested that the adsorption is mainly a chemical adsorption mechanism. U(VI) is adsorbed on PA-PANI-3 via the phosphoric acid, amine, and imine groups. The U(VI) can be desorbed from the U(VI) adsorbed PA-PANI-3 with a desorption efficiency of 90.8% by using 0.1 mol/L Na2CO3 solution. This study demonstrated that PA-PANI could be used as an efficient adsorbent for removal and recovery of U(VI) from aqueous solution.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Zhi Chen,Zanyong Zhuang,Qing Cao,Xiaohong Pan,Xiong Guan,Zhang Lin
The mechanism of the interaction between nano-Mg(OH)2 adsorbent and uranyl in water was studied. At trace levels, the uranyl is adsorbed as a monolayer on nano-Mg(OH)2, and occupied a small proportion of the adsorption sites. As the uranyl concentration crosses over a threshold, continuous increase of adsorption capacity takes place. It indicates that, by taking the pre-adsorbed uranyl as the nucleation centers, the additional uranyl crystallizes and forms U-rich nanocrystals well-scattered on the surface of nano-Mg(OH)2. A strategy of inducing fast crystal growth of nano-Mg(OH)2 to micrometer-sized Na2Mg(CO3)2 enables the desorption and enrichment of uranyl. The recycling and reuse of nano-Mg(OH)2 can be achieved simultaneously. The finding in this work provides fundamental understanding of the efficient usage of nano-Mg(OH)2 in practical applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
HYDROMETALLURGY
·
2014
·
IF 2.224
Mohannad Mayyas,Mohammad Al-Harahsheh,Xian-Yong Wei
Jordanian phosphate ore contains 70–150 parts per million (ppm) uranium. The uranium in the ore tends to dissolve during the leaching of phosphate ore with sulfuric acid to produce phosphoric acid (PA). Solvent extraction (SX) using various extracting agents is widely used to extract uranium from PA. Meanwhile, much research work has been carried out to develop suitable solid phase extractants in order to reduce cost and enhance efficiency. In this study, a new solid phase extractant has been synthesized by anchoring 2-hydroxy-4-aminotriazine onto activated carbon (ACH). The extraction of uranium from Jordanian PA using ACH and the synergistic mixture of di-ethylhexyl phosphoric acid and trioctyl phosphine oxide (DEPA–TOPO) diluted in kerosene were investigated and the performance of each extractant was evaluated and compared. The results showed that 91% extraction and 559.9 ppm loading capacity were achieved after 2 to 3 min mixing time using 0.5 M DEPA–0.125 M TOPO at 20 °C, 410 mV and 1/1 phase ratio. The activation energy ( E a ) of the solvent extraction (− 26.03 kJ mol − 1 ), calculated from Arrhenius plot, indicates that the reaction is barrier-less and exothermic in nature. On the other hand, uranium sorption onto ACH reaches equilibrium after 10 min and about 92% extraction can be achieved at 20 °C, C o = 70 mg/l, V = 200 ml, W = 100 mg and 410 mV; the rate constant for the uranium sorption onto ACH (16.54 × 10 − 3 g mg − 1 min − 1 ) was calculated from the pseudo-second order equation. The countercurrent extraction results showed that ACH has high physical, chemical stability and loading capacity about 618 mg g − 1 . Thermodynamic parameters ( ΔH ads ° = 20.61 kJ mol − 1 , ΔS ads ° = 160.47 J mol − 1 K − 1 , ΔG ads ° (333.3 K) = − 32.87 kJ mol − 1 ) suggest that the adsorption is endothermic and spontaneous in nature, which confirm the feasibility of the process.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Lin Zhou,Faqin Dong,Wei Zhang,Yuheng Chen,Lei Zhou,Fei Zheng,Zhenzhen Lv,Jingyuan Xue,Dengliang He
The biosorption and biomineralization behavior of U(VI) by Kocuria rosea with uranium resistance higher than other general microorganisms was investigated in this study. The results showed the obvious effects of initial U(VI) concentration, biomass, time, and especially pH, and presented that U(VI) was immobilized to K. rosea by physical and chemical action. The characterization results for the precipitation proved that U–P minerals with U(VI) (H 3 OUO 2 PO 4 ·3H 2 O, H 2 (UO 2 ) 2 (PO 4 ) 2 ·8H 2 O) or U(IV) (CaU(PO 4 ) 2 ) were dominant, and the crystallization level increased with time. In the process, the phosphorous containing groups, amino, hydroxyl and carboxyl groups played important roles in adsorption of U(VI), and the phosphate groups were crucial in immobilization of uranium, showing the importance of groups containing phosphorus in both biosorption and biomineralization processes. Our findings focus on the biosorption and biomineralization mechanism of U(VI) by K. rosea , emphasize the synergy of physical adsorption and chemical immobilization in the process and formation of U(VI)–P and U(IV)–P minerals, and highlight the significance of phosphorus involvement in the reaction.
研究领域:
微生物学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）