JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2022
·
IF 8.91
Jiequan Liu,Ruyi Zhou,Junxia Yu,Li Guo,Xiaodi Li,Chunqiao Xiao,Haobo Hou,Ruan Chi,Guoqing Feng
Potentially toxic elements including lead (Pb), manganese (Mn), and copper (Cu) released from copper tailings would cause severe long-term environmental risks and potential threats to human health. To prevent these negative effects caused by the release of the metals, a novel magnetic carboxyl groups modified bagasse with high adsorption affinity and strong magnetism was synthesized through an in-situ precipitation method and used to simultaneously remove Pb, Mn, and Cu from the eluate of copper tailings. Results showed that release of Pb, Mn, and Cu from the copper tailings was pH, time, and particle size dependent, and maximum concentrations of them released in the eluate was 1.7, 1.9, and 4.1 mg L −1 under weak acid conditions. Batch adsorption experiment showed that the as-synthesized magnetic modified bagasse could selectively absorb Pb, Mn, and Cu from a complex solution with adsorption capacity of 137.3, 13.1, and 90.0 mg g −1 , respectively. X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy-mapping (EDS-mapping) demonstrated that Pb, Mn, and Cu interacted with the magnetic modified biosorbent mainly through coordination and ion exchange. Column experiments showed that higher than 99.5% of the released Pb, Mn, and Cu could be simultaneously removed by the magnetic modified bagasse, and the maximum concentrations of them released in the eluate of the copper tailings were all decreased to lower than 0.01 mg L −1 , which reached the discharge standards. After recycled by a magnet, the magnetic modified bagasse could be collected easily and used repeatedly. Because of the high efficiency and easy recovery, the used method had great practical application value in removal of potentially toxic elements released from metallic tailings.
研究领域:
环境科学
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生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2025
·
IF 12.5
Jin Xu,Qirong Li,Jiugang Yuan,Xuerong Fan,Weidong Gao
Starch-based films suffer from brittleness and poor tensile properties, limiting their industrial applicability. In this study, magnetically modified starch (MMS) was prepared by covalently grafting azide-Fe 3 O 4 @SiO 2 nanoparticles onto the reducing ends of soluble starch via reductive amination and Cu(I)-catalyzed azide–alkyne cycloaddition (click chemistry). During film formation, application of a 1.4 T NdFeB magnetic field promoted chain alignment and crystallization. X-ray diffraction revealed a 19 % increase in crystallinity (from 9.6 % to 11.4 %), while FTIR analysis showed a 27 % enhancement in the (994 + 1047)/1022 ratio, indicating greater short-range molecular order. As a result, the tensile strength of MMS films increased to 19.8 ± 1.9 MPa, representing an 81.7 % improvement over native starch films (10.9 ± 1.4 MPa, p < 0.01). Meanwhile, the elongation at break decreased from 3.9 ± 0.8 % to 2.3 ± 0.3 %, reflecting enhanced molecular packing and reduced chain mobility. Superparamagnetic behavior ensured chain mobility only under field exposure, minimizing agglomeration after field removal. This work demonstrates a scalable, field-guided strategy to tailor starch film structure and performance, offering promising applications in eco-friendly packaging and biomedical materials.
研究领域:
材料科学
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食品科学
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高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainability
·
2022
·Vol. 14
·期 15
·9349
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IF 3.889
Yijia Chen,Linzhou Li,Qin Wen,Run Yang,Yiming Zhao,Xin Rao,Jihui Li,Shuying Xu,Hui Song
Magnetic modification holds a significant place for regulating the performance of biochar for wastewater treatment, endowing its magnetic separation property and facilitating its wide application. Herein, a ball-milled oxidative magnetic modification of pristine biochar was employed to manufacture magnetic biochar using K2FeO4as a precursor and internal oxidant for removal of methylene blue and tetracycline from aqueous solution. The characterizations showed that magnetic iron oxide and oxygen-containing groups were simultaneously introduced. Moreover, specific surface area and pore volume were remarkably enhanced from 0.7 m2/g to 71.2 m2/g and from 0.001 cm3/g to 0.034 cm3/g, respectively. The magnetic biochar showed that 133.76 mg/g and 58.34 mg/g adsorption capacities for MB and TC, respectively, significantly transcended the pristine biochar. Its adsorption was mainly dominated by oxygen-containing groups and iron species. This would provide an efficient oxidative magnetic modification for the preparation of oxygen-containing group-rich magnetic biochar for the removal of MB and TC.Keywords:ball-milling;oxidative magnetic modification;magnetic biochar;methylene blue;tetracycline
研究领域:
环境科学
·
材料科学
✓ 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）