CHEMOSPHERE
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2023
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IF 8.8
Lei Wu,Xiaolu Gong,Cong Ma,Lan Xu,Ming Li,Chen Lyu,Nan Sun
In this study, hydrogels generated by the Schiff base reaction between citral and chitosan (CS) were used for the first time to improve the anti-bacterial property of forward osmosis (FO) membranes. The composite membranes were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Water contact angle (WCA), Zeta potential and confocal laser scanning microscopic (CLSM). In the FO filtration experiment, the membrane performance of TFC-1 with 1 M sodium chloride solution as the draw solution and deionized water as the feed solution was the best, with the water flux of 25.54 ± 0.7 L m −2 h −1 and the reverse salt flux of 4.7 ± 0.4 g m −2 h −1 . Although the hydrogel coating produced a certain hydraulic resistance, the flux of the modified membrane was only reduced by about 8%, compared with the unmodified membrane. However, the anti-bacterial property ( Pseudomonas aeruginosa ) and anti-fouling properties (bovine serum protein and lysozyme protein) of the modified membranes were improved, showing good antibacterial properties (99%) and flux recovery rate (over 90%). The modified method has the advantages of easy access to raw materials, simple operation and no risk of secondary pollution, which can effectively reduce the cost of chemical cleaning and extend the service life of the membrane. The modification of membrane by chitosan-based hydrogel is a promising option in the field of membrane anti-bacteria.
研究领域:
材料科学
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膜科学与技术
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生物医学工程
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环境功能材料
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抗菌材料
✓ 已验证
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2014
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IF 2.822
Fu Liu,Bi-rong Ma,Dong Zhou,Li-Jing Zhu,Yin-Yi Fu,Li-xin Xue
A novel positively charged loose nanofiltration (NF) membrane was fabricated feasibly by UV-induced photografting polymerization of diallyl dimethyl ammonium chloride (DADMAC) on Polysulfone ultrafiltration membrane. A possible reaction mechanism was proposed that a linear chain structure and/or pyrrole like five-membered nitrogen heterocycles structure on the side chain were grafted to form the active barrier layer. NF membrane demonstrated a looser average pore size of 8.6 nm and positive charges surface. Owing to the nanoscale ultrathin nanoscale barrier layer and the combination of Donnan exclusion and steric hindrance , NF membrane exhibited good hydrophilicity , a high pure flux of 60 L/m 2 h (0.5 MPa), a good salt rejection to Mg 2+ (90.8%), Al 3+ (94.0%), Ca 2+ (91.5%), and a high dye rejection to methylene blue (99.4%) and congo red (100.0%) respectively. The salts rejection of NF membrane to different salts followed the order of AlCl 3 > CaCl 2 > MgCl 2 > NaCl > LiCl > MgSO 4 > Na 2 SO 4. NF membrane showed certain fouling resistance to seawater and BSA solution. The grafting polymerization kinetics were comprehensively investigated including irradiation time, monomer concentration and irradiation intensity. X-ray Photoelectron Spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurement were employed to investigate membrane chemistry, morphologies, and hydrophilicity.
研究领域:
材料科学
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环境工程
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膜分离技术
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高分子化学
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水处理
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2016
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IF 4.917
Hao Li,Samah Awadh Ali Mahyoub,Wenjie Liao,Shuqian Xia,Hechuan Zhao,Mengya Guo,Peisheng Ma
The magnetic biochars were easily fabricated by thermal pyrolysis of Fe(NO 3 ) 3 and distillation residue derived from rice straw pyrolysis oil at 400, 600 and 800 °C. The effects of pyrolysis temperature on characteristics of magnetic biochars as well as adsorption capacity for aromatic contaminants (i.e., anisole, phenol and guaiacol) were investigated carefully. The degree of carbonization of magnetic biochars become higher as pyrolysis temperature increasing. The magnetic biochar reached the largest surface area and pore volume at the pyrolysis temperature of 600 °C due to pores blocking in biochar during pyrolysis at 800 °C. Based on batch adsorption experiments, the used adsorbent could be magnetically separated and the adsorption capacity of anisole on magnetic biochars was stronger than that of phenol and guaiacol. The properties of magnetic biochar, including surface area, pore volume, aromaticity, grapheme-like-structure and iron oxide (γ-Fe 2 O 3 ) particles, showed pronounced effects on the adsorption performance of aromatic contaminants.
研究领域:
环境科学
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环境工程
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材料科学
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物理化学
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污染控制化学
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能源材料
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吸附科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2019
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IF 7.65
Zhenhua Lü,Feng Hu,Haiyan Li,Xiru Zhang,Sanchuan Yu,Meihong Liu,Congjie Gao
The development of high performance membrane is crucial for enhanced separation efficiency of nanofiltration process in treating wastewaters from dye and textile industries. In this work, a novel thin-film composite nanofiltration membrane with an asymmetric separation layer composed of relatively compact skin and loose body was designed and fabricated for improved perm-selectivity and antifouling property. Nascent composite membrane with loose poly(piperazine amide) (PA) separation layer was interfacially synthesized and performed with secondary surface reaction using an aqueous tannic acid (TA) solution. Membrane characterizations verified the formation of compact TA skin on top of the loose PA layer through forming covalent bonds via esterification reaction. Compared with the composite nanofiltration membrane with PA symmetric separation layer having the same glucose rejection of about 82.0%, the permeability to pure water of the composite membrane with PA/TA asymmetric separation layer was higher by 28.0%, the water fluxes to aqueous solutions dissolved with model anionic dyes of alizarin yellow R, sunset yellow and Congo red under steady state were higher by 50.3, 43.9 and 36.1%, and the steady-state flux declines were lowered by 27.8, 43.4 and 23.5%, respectively. Furthermore, the PA/TA-based membrane also exhibited better antifouling property and rejection ability to alizarin yellow R.
研究领域:
材料科学
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环境工程
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膜分离技术
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高分子化学
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水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2011
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IF 3.723
Hui Wang,Yuming Huang
Prussian-blue (PB)-modified γ-Fe 2 O 3 magnetic nanoparticles (PBMNPs) were successfully synthesized based on electric interactions between negatively charged [Fe(CN) 6 ] 4− and positively charged γ-Fe 2 O 3 nanoparticles. The in situ PB coating was generated by the coordinating reaction between the adsorbed [Fe(CN) 6 ] 4− and the ferric ions on the surface of γ-Fe 2 O 3 NPs. The as-prepared PBMNPs were characterized by FT-IR, XRD, TEM, and used to remove organic pollutants from aqueous solution, namely, using methylene blue (MB) as model compound. The experimental results showed that the target compound could be removed efficiently from solution over a wide pH range from 3 to 10 in the presence of PBMNPs as peroxidase-like catalyst and H 2 O 2 as oxidant. Under optimal conditions, MB could be removed completely after 120 min of reaction at 298 K; the chemical oxygen demand (COD) removal efficiency and the total organic carbon (TOC) abatement efficiency were 53.6% and 35%, respectively. Furthermore, the PBMNPs catalysts showed high magnetization, temperature tolerance, long-term storage and operational stability, and they could be readily separated from solution by applying an external magnetic field. Finally, a possible reaction mechanism for MB degradation was also discussed.
研究领域:
环境科学
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纳米材料学
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催化化学
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水处理技术
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环境功能材料
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
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2021
·
IF 7.086
Yougong Li,Ming Chen,Jilai Gong,Biao Song,Maocai Shen,Guangming Zeng
River sediments are considered as sinks of microplastics (MPs). Although numerous studies have been conducted on MPs pollution in river sediments, the impact of MPs on the environmental behavior of Cd (II) in river sediments is still unknown. In this work, the effects of six MPs (polyethylene, polypropylene , polystyrene , polyvinyl chloride , polymethyl methacrylate and polylactic acid) on the adsorption of Cd (II) by Xiangjiang River sediment and the transport of Cd (II) in sediment were studied. The results showed that the adsorption ability of sediment to Cd (II) decreased with the increase of the content of MPs in sediment. When the content of MPs in sediment increased to 10%, polypropylene had the greatest effect on the adsorption affinity of sediments to Cd (II). Moreover, the addition of MPs accelerated transport of Cd (II) in sediment, and the transport of Cd (II) in sediment increased with the increase of the content of MPs. The reason may be that after adding MPs, the adsorption capacity of sediment to Cd (II) decreases, and the mass transfer resistance of Cd (II) to sediment reduces, which leads to faster transport of Cd (II) in sediment. Especially, when the content of MPs in sediment increased to 10% (w/w), the saturation point of the breakthrough curve decreased by about 70 pore volumes. This work hopes to provide helpful views on the environmental behavior and risk assessment of Cd (II) in the presence of MPs.
研究领域:
环境科学
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污染
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地球化学
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水科学研究
✓ 已验证
DOI
高影响因子