Journal of Environmental Sciences
·
2018
·
IF 3.12
Fan Bu,Baoyu Gao,Qinyan Yue,Xue Shen,Wenyu Wang
Coagulation–ultrafiltration (C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling . In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride (PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV 254 and dissolved organic carbon removal efficiencies, and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases (HoB) and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances (HiS) and hydrophobic acid (HoA) fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure (TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.
研究领域:
环境工程
·
水处理技术
·
膜分离
·
有机地球化学
·
给水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2016
·
IF 5.557
Sikuai Xue,Chengcai Li,Jiuming Li,Hailin Zhu,Yuhai Guo
To improve hydrophilicity and anti-fouling property of the polytetrafluoroethylene (PTFE) flat microfiltration (MF) membrane, a facile method was developed to modify the membrane via the co-deposition of catechol (CA) and polyethyleneimine (PEI) followed by surface mineralization of γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560). The surface chemical composition, surface morphology, hydrophilicity and filtration performance of the PTFE flat membrane were investigated by ATR-FTIR, XPS, FESEM, WCA and pure water flux measurements, respectively. After using this low-cost and simple modification method, the PTFE flat membrane was endowed with excellent hydrophilicity, high water permeation flux and superior anti-fouling property. Then, the oil/water separation tests were conducted using the modified PTFE flat membranes. The size distribution of the oil droplets is between 0.12–1.44 µm and the mean pore size of pristine PTFE flat MF membrane is 0.22 µm. The as-prepared hydrophilized PTFE flat membranes possess an excellent oil resistant ability with oil rejection ratio near 99%. Finally, the surface stability of the modified membrane was studied and the mineralized membrane showed excellent acid resistant ability. Therefore, this facile strategy holds attractive potential practical application in water environmental remediation.
研究领域:
材料科学
·
环境工程
·
膜技术
·
表面化学
·
水处理
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2015
·
IF 4.143
Yan He,Fanfeng Zeng,Zhenghua Lian,Jianming Xu,Philip C. Brookes
Natural soil montmorillonite and kaolinite nanoparticles (NPs) were tested as efficient sorbents for organic contaminant (OC) removal through mimicking their natural environmental dispersive states. Sorption of both mineral NPs decreased with increasing pH with ionizable pentachlorophenol (PCP), but increased with pH with non-ionizable phenanthrene (PHE), within the pH range of 4–10. In contrast, sorption decreased consistently for both PCP and PHE, as a function of increasing ion concentration (0.001–0.1 mol L −1 ). Sorption differences were likely caused by the electrolytic conditions dependent upon surface chemistry of OCs and mineral NPs. The results confirmed that the highly dispersive soil mineral NPs would prevail over both engineered NPs and their regular μm-sized colloids for OC removal, due to their ecological advantages and higher sorption properties. This finding provided a realistic assessment of the environmental function of soil natural minerals in water once they are released from soil into OC polluted aqueous systems.
研究领域:
环境科学
·
土壤学
·
环境化学
·
纳米地球化学
·
污染控制
✓ 已验证
DOI
高影响因子
DESALINATION
·
2021
·
IF 9.501
Lihua Zhao,Zhiyu Liu,Faizal Soyekwo,Changkun Liu,Yunxia Hu,Qingshan Jason Niu
Sludge thickening from sewage treatment plants is an essential step in reducing the sludge volume and processing cost of the subsequent treatment. Forward osmosis (FO) technology is one of the research endeavors used in the field of membrane separation and feed solution concentration. However, the traditional used single-skinned FO membranes encounter the problems of serious internal concentration polarization (ICP) and fouling phenomenon within porous substrates . A novel double-skinned FO membrane was proposed in this study in order to enhance the anti-fouling performance and mitigate the ICP phenomenon. Single-skinned FO membrane using the same substrate was also fabricated. Results demonstrated that the double-skinned FO membrane significantly reduced ICP and exhibited higher flux when using draw solutions with high concentrations as compared to the single-skinned FO membrane. Furthermore, the double-skinned FO membrane demonstrated reasonably high-water flux (11.6 LMH), whereas zero flux was recorded from the single-skinned FO membrane when using the feed solution that contained 15.0 g/L organic foulants in the fouling tests. At last, the double-skinned FO membrane exhibited superior anti-fouling properties and much higher flux than that of single-skinned FO membrane operated under both modes during the long-term sludge thickening process, indicating the great potential of the double-skinned FO membrane to deal with the high-water-content sewage sludge in the water treatment process.
研究领域:
环境工程
·
膜科学与技术
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水处理
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分离科学
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环境功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2020
·
IF 3.442
Deqiang Feng,Jie He,Lingcheng Zheng,Wenjun Jiang,Ce Zhang,Long Li,Jian Song,Wei Yao
Developing novel catalysts and catalysis processes are highly attractive in environmental protection and energy utilization. Photocatalysis-Fenton combinational process is an environmentally friendly technology and has broad application prospects. In this work, thin Fe@α-Fe 2 O 3 nanosheets with thickness of 2–5 nm were designed by oxidation of Fe metal nanostructure synthesized using a modified solution reaction method. The nanosheet structure with thin thickness has short diffusion distance for the photogenerated carriers and prolongs the carriers' life. Simultaneously, the presence of Fe can reduce the resistance of system and further promote the transport and transfer of photogenerated carriers from the bulk to the surface, causing less carrier recombination and better photocatalytic performance. What's more, the Fe@α-Fe 2 O 3 composite can induce the Fenton-like reaction to generate active • OH radicals, which significantly improve the degradation rate . The synergistic effect of photocatalysis and Fenton processes makes the system show an enhanced photodegradation performance: 96.5% of RhB is degraded after 60 min visible light irradiation , especially, 84.3% of RhB is degraded within the first 10 min, which are much higher than that of the pure α-Fe 2 O 3 sample. This work demonstrates that the conjunction of photocatalysis and Fenton processes based on the Fe@α-Fe 2 O 3 nanosheets provides a potential application for pollutants degradation.
研究领域:
环境化学
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材料科学
·
催化化学
·
纳米科技
·
物理化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2015
·
IF 7.435
Peng Yi-Zhu,Ma Wan-Hong,Jia Man-Ke,Zhao Xiao-Rong,David M. Johnson,Huang Ying-Ping
In this study, a weakly polar pesticide acetochlor in water was tried to degrade by BiOBr catalysts under visible light irradiation. Its degradation reaction rate increased exponentially with increasing catalyst dosage, which was significantly different from conventional photocatalytic patterns established for polar or water-soluble pollutants. Thus, the rate-dosage relationship of BiOBr/acetochlor was compared to that of BiOBr/Rhodamine B (RhB) (a typical strong polar dye pollutant in water) at different BiOBr dosages. The degradation rate of RhB increased with the BiOBr dosage and then plateaued due to more catalyst particles blocking the light into the inner solution, which is a typical behavior for heterogeneous photocatalysis of polar organic compounds in aqueous solution. While acetochlor behaved differently, its degradation rate increased exponentially with the BiOBr dosage, and no plateau was observed even up to 9.0 g/L BiOBr dosage. This special rate-dose relationship for weakly polar acetochlor was correlated with a unique adsorption property of BiOBr to acetochlor in water solution. There was a re-distribution effect that always exclude excessive acetochlor adsorbed on BiOBr surface regardless either substrates or BiOBr overdose. This finally resulted in every BiOBr particle having enough adsorption sites available for dissolved dioxygen to function thereby accelerate the degradation of weakly polar organic compounds in water.
研究领域:
环境化学
·
光催化
·
水污染控制
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环境功能材料
·
污染物降解机制
✓ 已验证
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Xiao Wang,George Q. Chen,Wei Zhang,Huining Deng
The development of reliable anion exchange membranes (AEMs) with superior antifouling properties is critical in practical applications of electrodialysis processes. For the first time, the AEMs were modified by poly (sodium 4-styrene sulfonate) (PSS) with titanium dioxide (TiO 2 ) nanoparticles using only one electrodeposition step to stabilize the nanoparticles on the membrane surface while improving their antifouling ability. Owing to the bonding between the sulfonic groups of PSS and TiO 2 , the TiO 2 nanoparticles were well dispersed in the modified layer. The deposition of PSS endowed the AEMs with a negatively charged surface, while the addition of TiO 2 nanoparticles further increased the charge density. The membrane resistance increased only marginally after 100-min of fouling experiments using sodium dodecyl benzene sulfonate (SDBS), due to the presence of TiO 2 on the modified AEMs. Ultraviolet (UV) irradiation was proven to be an effective approach in inducing good fouling reversibility of the TiO 2 -PSS modified AEMs through photocatalytic decomposition and hydrophilicity improvement.
研究领域:
膜科学
·
环境工程
·
材料化学
·
电化学
·
水处理技术
✓ 已验证
DOI
高影响因子
Journal of Oceanology and Limnology
·
2021
·Vol. 39
·期 5
·1622-1633
·
IF 1.265
Qu Yang,Xu Kuidong,Li Tao,Wang Maoyu,Zhong Huan,Chen Tianyu
The ocean is an important inventory of anthropogenic mercury (Hg), yet the history of anthropogenic Hg accumulation in the ocean remains largely unexplored. Deep-sea corals are an emerging archive of past ocean chemistry, which take in sinking or suspended particulate organic matter as their food sources. Such organic matter would exchange Hg with the local seawater before being consumed by the deep, sea corals. As such, the organics preserved in the coral skeleton may record the Hg evolution of the ambient seawater during the time of coral growth. Here, we report the first data on Hg concentrations variability of a deep-sea proteinaceous coral in the oligotrophic North Pacific at the water depth of 1 249 m, in attempt to understand the transfer of anthropogenic Hg into the deep Pacific ocean over the last seven centuries. We find that the Hg concentrations of different coral growth layers have remained relatively constant albeit with considerable short-term variability through time. The overall stable Hg concentration of the last seven centuries recorded in our sample suggests that anthropogenic pollution is not yet a clearly resolvable component in the deep oligotrophic North Pacific waters, in agreement with recent estimation from modelling works and observational studies of modern seawater profiles. As there is hardly an unambiguous way to separate anthropogenic Hg from the natural background based on recent seawater profiles, our historical data provide valuable information helping to understand the oceanic cycle of Hg through time.
研究领域:
海洋地球化学
·
环境科学
·
古气候学
·
生物地球化学循环
·
深海生态学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Wei Teng,Nan Bai,Zehan Chen,Junming Shi,Jianwei Fan,Wei-xian Zhang
Porous carbon is the most important and most common adsorbent for the separation and treatment of organic pollutants. Characteristics such as accessible and large surface area, physical and chemical stability, and low-cost manufacturing method are desired for any adsorbent. Herein, a hierarchically porous carbon (HPC) was prepared by pyrolysis and graphitization of crystalline metal–organic frameworks (MOF-5) for enhanced adsorption of aromatic contaminants. The material treated at high temperature (950 °C) possesses large surface area (1512 m 2 /g), high porosity (0.94 cm 3 /g), and hierarchically porous structures. The generated mesopores around 4 nm improve the interconnectivity of micro- and macropores to make the porous material ideal for sorption of organic pollutants such as aromatic hydrocarbons. Effects of adsorbent dose, pH, ionic strength, contact time, and initial concentration on the adsorption of p -nitrophenol (PNP, as a model) were investigated. Adsorption isotherms and kinetics suggest that the adsorption is a spontaneous and endothermic physisorption process with monolayer surface coverage. The surface sites are electron-rich due to the graphitic layer, which has high affinity toward π electrons of the aromatic ring. The adsorption capacity of the hierarchically porous carbon (HPC) is nearly over 100% higher that of conventional activated carbon.
研究领域:
环境科学
·
材料科学
·
物理化学
·
吸附分离
·
污染治理
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·Vol. 10
·期 6
·108733
·
IF 7.968
Hanhan Huang,Zhaosong Li,Haiyan Wang,Caifeng Xia,Pingke Yan,Qian Zhang,Zilin Meng
Microplastics (MPs) are widely presence in soil, and the uncertain influence of MPs is ineluctable. In this study, the influence of removal efficiency for heavy metals by LDHs with the presence of polyethylene (PE) and polypropylene (PP) is investigated. And the removal efficiency of heavy metals Cu 2+ , Pb 2+ , Zn 2+ , Ni 2+ by LDHs from soil is investigated by contact time, initial concentration, PP/PE contents, pH and coexisting ions. The adsorption capacities of heavy metals with the presence of PP/PE are larger and the effects with high content of PP/PE is more obvious on removal of heavy metals. The isothermal experiment data are well described by the Generalized Langmuir isothermal model, denoting that the adsorption sites on the absorbents are certain, and the sites are inhomogeneous with different adsorption energy. In order to further explore the influence of PP/PE on the removal of heavy metals by LDHs, the interaction between LDHs and PP/PE is analyzed by XRD , FT-IR, Zeta potential and SEM. The sites energy distribution theory is employed to analyze the distribution of accessible adsorption sites and the heterogeneity of sites. The results show that with the presence of PP/PE in soil, LDHs interacts with PP/PE preferentially on account of electrostatic attraction, and the combination of LDHs and PP/PE increases the accessible adsorption sites for the removal of heavy metals and is beneficial to the adsorption process . These findings contribute to understanding environmental behavior of heavy metals with the presence of MPs and guide the application of LDHs in soil.
研究领域:
环境科学
·
土壤修复
·
纳米材料应用
·
环境污染化学
·
吸附动力学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2019
·Vol. 40
·期 5
·631-637
·
IF 4.914
Zhenmin Xu,Ru Zheng,Yao Chen,Jian Zhu,Zhenfeng Bian
Ordered mesoporous Fe/TiO 2 was prepared by an evaporation-induced self-assembly method. The iron ions were in situ embedded in the pore wall of the TiO 2 framework. The catalyst has excellent light-assisted Fenton catalytic performance under UV and visible light irradiation. X-ray diffraction and transmission electron microscopy results showed that the TiO 2 samples have an ordered two-dimensional hexagonal pore structure and an anatase phase structure with high crystallinity . The ordered pore structure of the TiO 2 photocatalyst with a large specific surface area is beneficial to mass transfer and light harvesting. Furthermore, iron ions can be controlled by embedding them into the TiO 2 framework to prevent iron ion loss and inactivation. After five cycles, the reaction rate of the ordered mesoporous Fe/TiO 2 remained unchanged, indicating that the material has stable performance and broad application prospects for the purification of environmental pollutants .
研究领域:
材料科学
·
环境化学
·
催化化学
·
纳米科技
·
光化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Shaojie Zhang,Chao Yu,Na Liu,Yun Teng,Cuiyu Yin
In this study, cellulose pulp and urea were used to synthesize cellulose carbamate (nitrogen content reaches 4.5%) by low-cost and environmentally friendly solid-liquid phase method. Cellulose carbamate fluid was prepared by using sodium hydroxide aqueous solution as solvent. The fluid was regenerated and formed in a coagulation bath , and finally a regenerated cellulose membrane with high transparency and separation ability was obtained. The simple chemical treatment of cellulose not only greatly increased the mass fraction of cellulose dissolution (It has reached 15%) and retains the original crystal form and thermal stability of cellulose. The surface of the membrane was relatively dense, and the inside has regular microchannel . The factors affect the transparency and water flux of regenerated cellulose membranes were discussed by orthogonal experimental range analysis. The ability of the regenerated cellulose membrane to reject dyes was tested. The results showed that the rejection of methyl blue and congo red reached 100%, and the rejection rate of methyl orange reached 60%. The oil/water separation ability and the anti-pollution ability of the regenerated cellulose membrane were tested. The oil/water separation effect reached 100%. This membrane may have application prospect in water treatment, biotechnology.
研究领域:
材料科学
·
环境工程
·
膜技术
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）