CHEMOSPHERE
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2021
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IF 7.086
Hanyu Wu,Jie Chen,Zengbo Su,Bin Ma,Yizhe Ji,Shuhan Lin,Dingfang Xu,Mingliang Kang
Europium(III), i.e., Eu(III), is chemically analogous to the trivalent lanthanides (Ln) and actinides (An). A good understanding of the adsorption behaviour of Eu(III) on mica group minerals is critical to the safety evaluation of the radioactive contamination. Nevertheless, the structural complexity of micaceous minerals makes it difficult to draw a consistent conclusion in the study of Eu(III) migration. In this work, we contrastively studied Eu(III) adsorption on dioctahedral muscovite and trioctahedral phlogopite as functions of pH, ionic strength, background electrolytes, interaction sequence, and fulvic acid (FA). Batch experiments showed that Eu(III) adsorption on both micas was strongly dependent on pH but quite independent on ionic strength that is determined by Na + . Planar sites are available on both muscovite and phlogopite while interlayer sites only on phlogopite under Na + and Ca 2+ electrolytes (not for K + and Cs + ). An interlayer expansion of phlogopite, as indicated by a newly appeared diffraction peak at ~6° 2-theta, occurred along with Eu(III) adsorption, which was also confirmed by transmission electron microscopy . Furthermore, the initial Eu(III) concentrations, the concentration ratios between Eu(III) and Cs + , and the reaction sequences of Eu(III)-electrolytes-FA affected both the adsorption behaviour of Eu(III) and reversely the structural alteration of phlogopite. The sequential extraction showed that the adsorbed Eu(III) was mainly in the ion-exchangeable form while the addition of FA could increase the portion of coordinative species. The currently proposed Eu(III) adsorption mechanism can shed new light on predicting the migration of Ln/An(III) at the mica-rich solid-liquid interface on a molecular scale.
研究领域:
环境科学
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放射化学
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矿物学
✓ 已验证
DOI
PubMed
高影响因子
POWDER TECHNOLOGY
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2023
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IF 5.2
Ming Liu,Guoqiang Shao,Pengpeng Lv,Jun Li,Qingshan Zhu
The fluidization quality significantly affects the mass transfer and the deposition reaction, which determine the uniformity of deposited TiO 2 thin films on fluorophlogopite particles. It was found that the effective addition ratio of nano-TiO 2 particles is above 0.2 wt% to realize fluidization of fluorophlogopite particles. The addition of nano-TiO 2 particles leads to competitive deposition between free TiO 2 particles and fluorophlogopite particles, which decreased the coating rate of TiO 2 on fluorophlogopite particle. Besides, the existence of free TiO 2 particles on pearlescent pigment particles decreases the glossiness. The gas-solid ratio primarily determines the number of the free TiO 2 particles on pearlescent pigment particles. It was summarized that the optimal value of addition ratio of nano-TiO 2 is 0.4 wt% with the gas-solid ratio of ∼0.05 m 3 kg −1 h −1 to enhance the fluidization quality on the one hand, and to reduce the free TiO 2 particles on the other hand.
研究领域:
化学工程
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材料科学
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
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2025
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IF 2
Shizong Wang,Jianlong Wang,Xuan Guo
This study evaluated the uranium removal performance and mechanisms of six minerals: zeolite, montmorillonite, bentonite, phlogopite, sodium bentonite (Na-bentonite), and potassium feldspar (K-feldspar). When the initial uranium concentration was 10 mg/L, montmorillonite exhibited the highest uranium adsorption capacity, reaching 64.9%, followed by bentonite (63.3%), zeolite (57.2%), phlogopite (53.3%), Na-bentonite (37.3%) and K-feldspar (35.7%). The adsorption process was pH-dependent, with bentonite and zeolite showing enhanced adsorption at higher pH levels, while other minerals exhibited complex trends due to changes in uranium speciation and mineral surface properties such as electronegativity. Mechanistic analysis revealed that zeolite, phlogopite and K-feldspar removed uranium mainly through chemical adsorption, such as structural incorporation and surface complexation, whereas montmorillonite, bentonite and Na-bentonite mainly removed uranium via physical adsorption such as ion exchange and electrostatic attraction. Phlogopite exhibited strong uranium retention via interlayer adsorption, whereas Na-bentonite and K-feldspar exhibited weaker adsorption due to lower cation exchange capacity and surface interactions. Thermodynamic studies indicated that adsorption onto montmorillonite, bentonite, zeolite, and phlogopite was spontaneous and exothermic, whereas Na-bentonite and K-feldspar showed endothermic behaviour. Stability tests in bicarbonate solution confirmed phlogopite’s highest uranium retention, whereas bentonite and montmorillonite released more uranium due to bicarbonate complexation. These findings provide insight into uranium adsorption mechanisms and serve as a reference for the selection of materials for radioactive waste disposal repositories.
研究领域:
环境科学
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地球化学
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放射化学
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材料科学
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核废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
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IF 0
Cai Fangfei,Zhang Xiaoying,Ma Funing,Qi Linlin,Lu Di,Dai Zhenxue
The distribution coefficient ( K d ) of radionuclides is a crucial parameter in assessing the safety of high-level radioactive waste (HLW) geological repository. It is determined in the laboratory through batch and column experiments. However, differences in obtained K d values from distinct experiments have not been thoroughly assessed and compared. This study evaluated strontium (Sr) sorption on different granite materials using static batch and dynamic experiments (column and core-flooding experiments). The results from batch sorption experiments showed higher Sr sorption on granite under acidic and strongly alkaline conditions, low solid–liquid ratios, and low ionic strength. In column experiments, a two-site sorption model was used to simulate Sr transport in crushed granite and mixed pure minerals. The sorption of Sr on crushed granite exhibited a higher affinity than that of mixed pure minerals. The dual-porosity transport model was employed to investigate Sr transport behavior in fractured granite in the core-flooding experiment. K d obtained from batch sorption experiments are four to twenty times higher than those from column experiments, and two to three orders of magnitude higher than that from a core-flooding experiment. The results of this study provide valuable insights into safety assessment for the HLW geological repository.
研究领域:
环境科学
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放射性废物管理
✓ 已验证
产品关联
DOI
PubMed
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
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2024
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IF 3
Ma Xin-Yue,Cao Fang-Chao,Tang Yan,Jiang Jun-Cheng,Huang An-Chi
In this paper, a modified material EG-PR with hydrophobic and oleophobic properties was successfully prepared with expanded graphite (EG) as the main raw material and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PR) and silane coupler KH-570 (KH) as surface modifiers. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy verified the effective modification that produced a Si‒O‒Si network structure. The water contact angle (WCA) of 127° and oil contact angle (OCA) of 110° of EG-PR, unmodified EG-IA, were 92° and 20°, respectively. Fire-extinguishing tests conducted on heptane pool fire showed that EG-PR decreased the time required to extinguish the fires by 23 s, consumed less extinguishing agent, and suppressed the production of carbon dioxide during combustion compared to EG-IA, indicating its higher effectiveness. EG-PR demonstrated rapid fire-extinguishing capabilities during the experiments. It effectively extinguished the flames, created a protective layer on the oil pool’s surface, efficiently isolated heat and oxygen, and effectively suppressed flame propagation on the surface. This study highlights the potential of surface-modified expandable graphite in enhancing fire safety applications. Graphical abstract
研究领域:
材料科学
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消防工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Daheng Wu,Jianing Wang,Yuxiang Zhao,Shengfei Li,Haoyong Yang,Runxiang Tan,Tao Zhang
The widespread use of petroleum-based plastics brings potential hazards to the ecological environment. In order to solve this issue, the development of biodegradable materials with both high mechanical, barrier performances and food safety is imminent. In this work, a natural nacre-inspired seaweed-based nanocomposite material with the structure of “brick and mortar” is synthesized by rational assembling mica nanosheets in a mixture of glycerol and sodium alginate. The resultant SA/nano-mica film (1 wt% of phlogopite powder) shows high thermal stability (>180 °C) and exhibits great tensile strength of ∼ 16 MPa at ambient condition, surpassing some other reported nanocomposite materials (1.9–14.74 MPa). Meanwhile, the composite can be easily processed into different shapes for packaging applications, which could long-term preserve the freshness of foods owing to their strong ultraviolet (UV) shielding and gas barrier properties (UV transmittance of ∼ 4 % and oxygen transmission rates (100 µm) of ∼ 18.52 cc m −2 day −1 bar −1 ). Importantly, the material could completely degrade in soil within 15 days. These results indicate the great application prospect of seaweed-based nanocomposite materials in food packaging.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）