Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Guowei Chen,Minghui Qiu,Wei Ke,Xianfu Chen,Yiqun Fan
Membrane technology is an efficient approach for separation of polyvinyl alcohol (PVA)-starch desizing wastewater. However, fouling caused by complex components remains a challenge in industrial-scale applications, leading to reduced flux and frequent chemical cleaning. Here, we utilize PVA components in wastewater to form a self-forming dynamic membrane (SFDM) on substrate surface during filtration, thereby improving the anti-fouling properties of the ceramic membrane as well as its retention performance for small molecule starches generated through decomposition in a high temperature and strong alkali system. We investigated the effects of pore sizes in porous ceramic on starch separation performance and dynamic membrane formation in the simulation system of PVA-starch. In an industrial desizing wastewater treatment system, we verify the stability and reproducibility of SFDM technology. The results demonstrate that ceramic membranes with a pore size of 20 nm are conducive to forming complete SFDMs, resulting in an increase in starch retention from 75.6 % to 99.9 %, while maintaining flux at 59 L·m −2 ·h −1 . The removal rates of COD, TOC and turbidity are 76.2 %, 68.3 % and 99.9 %. SFDMs can form quickly and reduce irreversible fouling on ceramic membranes. The use of ceramic-supported PVA SFDM provides valuable insights for applying ultrafiltration technology to complex wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
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2018
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IF 2.891
Bo Gao,Weiping Chen,Jiadong Liu,Jiajun An,Lei Wang,Ying Zhu,Mika Sillanpää
Based on the concept of dynamic membrane and photocatalytic membrane reactor (PMR), the dynamic photocatalytic membrane reactor is developed via deposition of ZnIn 2 S 4 suspension on polyvinylidene fluoride (PVDF) membrane. Operating with effluent circulating to the photocatalytic membrane reactor, the highest total organic carbon (TOC) removal efficiency of 57% is obtained after 3 h reaction with 1.88 mg cm −2 photocatalyst under the flux of 84.06 L m −2 h −1 and light intensity of 50 mW cm −2 . Operating with continuous influent and effluent mode under the flux of 26.09 L m −2 h −1 and light intensity of 50 mW cm −2 , an average of 50% removal efficiency can be maintained during the 24 h photocatalytic reaction with photocatalyst loading of 1.88 mg cm −2 when the initial concentration of tetracycline is 10 mg L −1 . Under the same operating conditions, more than 92% removal efficiency can be maintained during 36 h photocatalytic reaction when lower initial concentration of 100 μg L −1 is applied. After this reaction, the characterizations show that the surface and structure of PVDF basement membrane are not affected.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Xiaoxiang Cheng,Yinuo Liu,Xinsheng Luo,Xuewu Zhu,Jingtao Xu,Xinyu Zhang,Daoji Wu,Feiyong Chen,Heng Liang
The construction of replaceable dynamic membranes (DMs) on membrane surfaces is a promising strategy to effectively mitigate membrane fouling . Nevertheless, the efficiency of DMs in mitigating membrane fouling remains low due to the lack of microstructural configurations. Herein, we report a natural sepiolite (SEP) DM with a three-dimensional (3D) network structure for mitigating PES ultrafiltration (UF) membrane fouling. The abundant oxygen-containing groups on the surface of SEP nanofibers endowed SEP DM with good organic adsorption capacity, hindering the migration of contaminants such as humic acid (HA) and bovine serum albumin (BSA). Owing to the porous 3D network structure, SEP DM prevented the formation of a dense filter cake layer, which effectively mitigated the sharp rise in membrane resistance when filtering ideal HA and BSA solutions. For the actual secondary wastewater, SEP DM improved the removal of UV 254 and DOC by 29.8% and 22.5%, respectively, over the pristine PES membrane. The decrease in membrane-specific flux was mitigated by about 20%. Notably, the dynamic nature of SEP DM allowed the contaminated DM layer to be replaced by hydraulic cleaning, resulting in 99% flux recovery (only 89% for the pristine PES membrane). These findings are beneficial in providing new ideas for the mitigation and control of UF membranes.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Frontiers of Chemical Science and Engineering
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2020
·Vol. 14
·期 6
·1018-1028
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IF 3.552
Zeng Jiehui,Zeng Jianxian,Zhou Hu,Liu Guoqing,Yuan Zhengqiu,Jian Jian
An ion-imprinted sorbent (IIP) was prepared by using Ni 2+ as template, 3-[2-(2-aminoethylamino) ethylamino] propyl-trimethoxysilane as functional monomer, and silica gel as carrier. The adsorption performance of IIP towards Ni 2+ was investigated. IIP showed a higher adsorption capacity than that of non-imprinted sorbent, and it also exhibited high selectivity for Ni 2+ in the presence of Cu 2+ and Zn 2+ ions. Then, IIP was used to form a dynamic membrane onto the surface of ceramic membrane for treatment of electroplating wastewater containing Ni 2+ . Compared with ceramic membrane, IIP dynamic membrane had much higher steady membrane flux, and also rejected Ni 2+ to obtain a lower concentration of Ni 2+ in the permeate fluid. Perhaps it is suitable for future practice applications.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2022
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IF 7.34
Wenxiang Zhang,Jiahao Mo,Wenzhong Liang,Xing Du
Membrane technology plays an important role in water purification , but there are some significant challenges such as membrane fouling and deep purification efficiency. The work proposes a carbon nanotube-adsorptive dynamic membrane (CNT-ADM), including carbon nanotube (CNT) and membrane module, to solve these problems with low operating cost and high removal efficiency. Above all, on the basis of physical adsorption and membrane separation , a CNT-ADM was prepared by applying “forward filtration” of a CNT solution on an ultrafiltration membrane surface. Then, the effects of preparation time, CNT loading amount, transmembrane pressure (TMP) and shear stress on the morphology and permeability were analyzed to evaluate the preparation performance. Pore blocking models were utilized to explain the influence of CNT loading amount on membrane fouling mechanism. The best optimized condition for CNT-ADM preparation was: agitation speed of 50 rpm, TMP of 1 bar, CNT loading amount of 55 g/m 2 and preparation time of 10 min. Furthermore, the optimized CNT-ADM was employed to treat the micro-polluted water. The effects of treatment condition on the micropollutant removal rate and flux were investigated with various shear stresses, TMPs, the amounts of micropollutant and CNT. Compared with the new membrane (below 10 %), CNT-ADM displayed a significant improvement for the micropollutant removal (above 95 % for three cycles), due to the synergy of membrane separation (sustaining CNT layer, separating micropollutant and increasing adsorption time) and adsorption removal (forming CNT layer and adsorbing micropollutant). On the other hand, the adsorption behavior also could effectively reduce the direct contact between membrane and micropollutant, then decreasing membrane fouling. Afterwards, the backwash cleaning was also successfully applied to alter the adsorption saturated CNT and generate the new CNT layer. In final, the implications for CNT-ADM application were discussed. Overall, CNT-ADM exhibits the desirable micropollutant removal and strong anti-fouling capacity, and has a great potential application in the sustainable water purification.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CHEMOSPHERE
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2019
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IF 5.108
Zhenzhou Zhu,Zhe Chen,Xiao Luo,Wenzhong Liang,Shuyi Li,Jingren He,Wenxiang Zhang,Tianwei Hao,Zi Yang
Biomimetic dynamic membrane (BDM) has been employed as a promising membrane separation technology regarding water/wastewater treatment (Model pollutant is methylene blue). Given its catalytic function on micro-pollutant removal and fouling control, detailed mechanism for impacts of fabrication method, carriers (CNT and GO) and laccase on the construction of biomimetic layer and enzyme immobilization have not been clear so far. In this work, the BDM performance with various fabrication methods, carriers and laccase were investigated and verified. The BDM fabrication tests demonstrated that BDM with mixed filtration method had better filtration performance (up to 120 L m −2 h −1 flux and 80% removal rate) than BDM with stepwise filtration method. Moreover, the laccases immobilized on GO exhibited a stronger laccase activity than those on CNT. Increasing CNT or GO dosage strengthened removal rate, but lowered flux, meanwhile flux and removal rate exhibited a significant fluctuation with certain laccase dosage. At 25 g m −2 CNT or GO dosage and 50 g m −2 laccase dosage, the optimized flux and removal rate values were obtained. Further study investigated the surface morphology and property of BDM, showing that BDM with mixed filtration method turned out to be the optimized enzyme immobilization mechanism and fabrication method. In addition, during multiple filtration cycles, with the optimized conditions, the removal rate, flux and laccase activity of BDM could maintain at high levels. On account of the finding of the present study, selecting a suitable fabrication method, appropriate CNT or GO dosage and laccase dosage can indeed optimize the structure of biomimetic layer and enzyme immobilization, expanding its possibility on sustainable operation.
研究领域:
环境科学
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生物技术
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水处理工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
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IF 6.361
Senlin Shao,Yang Liu,Danting Shi,Weihua Qing,Wenwen Fu,Jiangyun Li,Zheng Fang,Yiqun Chen
Hypothesis A superhydrophilic membrane with rough and hierarchical structures is possibly fouled by surfactant-stabilized oil and organic foulants, because these foulants could not be hindered by the water layer formed on superhydrophilic membrane surface. A dynamic membrane was possibly an effective method to address this fouling problem. Experiments A microfiltration membrane, a nanofiber membrane, and a dynamic membrane were used for the separation of surfactant-free emulsions, surfactant-stabilized emulsions, and the surfactant-stabilized emulsions containing typical organic foulants. The oil rejection and membrane fouling were compared. Findings The microfiltration membrane, nanofiber membrane, and dynamic membrane had high resistances to the fouling by surfactant-free emulsions because these membranes were underwater superoleophobic. However, these membranes showed low resistances to the fouling by surfactant-stabilized oil droplets and organic foulants. For the dynamic membrane, the oil droplets and organic foulants trapped in the separation layer could be readily removed in the detachment-washing-recoating steps; therefore, almost no physically irreversible fouling was observed in the multi-cycle filtration. With the size distributions of oil droplets in the emulsions and the particle of the dynamic membrane, the rejection of oil by the dynamic membrane could be calculated by simply assuming that the particle was spherical, uniform, and tightly packed.
研究领域:
环境工程
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膜科学
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产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
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2018
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IF 7.051
Wensong Chen,Jiahao Mo,Xing Du,Zhien Zhang,Wenxiang Zhang
This study utilized physical adsorption and filtration of carbon nanotubes (CNTs) and laccases to fabricate biomimetic dynamic membrane (BDM) for the advanced treatment of dye wastewater. In BDM, the adsorption, enzymatic degradation and membrane separation demonstrated a synergism effect on pollutant removal . At first, the fabrication methods of BDM were investigated, and the mixed filtration for laccases and CNTs showed a better performance than the stepwise filtration. Furthermore, the operation parameters of BDM, including CNTs and laccase loading amounts, dye concentration, agitation speed and transmembrane pressure (TMP), were studied. Suitable CNTs and laccase amounts could reduce filtration resistance and increase catalysis efficiency, while moderate TMP and agitation speed were in favor of boosting the BDM structure for catalysis and permeability. Optimized operation parameters (CNT loading amount = 20 g m −2 , laccase loading amount = 74.6 g m −2 , agitation speed = 100 rpm, and TMP = 1.0 bar) sustained a high removal rate, and the flux was over 120 L m −2 h −1 , even for 7 operation cycle’ tests. BDM exhibited an excellent dye removal rate, stable flux and great antifouling capacity, on the ground that adsorption saturation and foulant may be alleviated “online and in-situ” by the enzymatic degradation. Afterwards, the bionic layer on BDM, after absorption saturation and catalyst deactivation, could be eliminated rapidly by carrying out a simple backwash cleaning operation, then a new one could be fabricated immediately. Therefore, BDM is a good candidate for functional membrane materials in future water treatment .
研究领域:
环境科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2022
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IF 10.53
Guichang Chen,Jinlan Wen,Yang Yu,Mai Liu,Guoqiang Liu
Previous studies found that the inhabitation of filamentous bacteria on the support materials with large apertures in dynamic membrane bioreactor (DMBR) could stabilize the DM structure and resulted in stable effluent quality. However, it is hard to cultivate the filamentous bacteria on support materials in DMBR intentionally. In present study, a polyvinyl alcohol (PVA) nanofiber layer was coated on 180-μm nylon mesh to simulate the inhabitation of filamentous bacteria. The nanofiber coated mesh with 1 h spinning time (referred as PVA-1h) had a similar porosity (14.9%) to that of 25-μm nylon mesh and dominant pore size of 1.0–2.5 μm. Short-term test indicated that the PVA-1h had a low initial effluent turbidity of 5.3 NTU and could form DM within 5 min. Long-term test in DMBR demonstrated that better and more stable effluent quality (0.71 ± 0.31 NTU) was achieved by PVA-1h compared to typical used support materials of 25-μm mesh (1.04 ± 0.60 NTU). However, the PVA-1h had an operation flux of 30–50 L/(m 2 ·h) with a water head loss ≤2 cm, which was comparable with the 25-μm mesh but much greater than that of 2.6-μm mesh (<5 L/(m 2 ·h)). In addition, the filtration resistance change between the PVA-1h and 25-μm mesh were very similar. Therefore, this study demonstrated that with proper density of nanofiber as the skeletons, DMs would be formed more quickly and stably, resulting in better and more stable effluent quality in DMBR without sacrificing operation flux.
研究领域:
环境工程
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生物学
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产品关联
DOI
高影响因子
Results in Engineering
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2023
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IF 5
Wenxiang Zhang,Wenzhong Liang,Xing Du
Adsorptive dynamic membrane, consisting of adsorption and filtration, exhibits a desirable efficiency for water purification. However, the entire adsorption-filtration process is affected by many influencing factors, and the operating regulation and process optimization remain still uncertain. The present work deals with the process optimization for adsorptive dynamic membrane treating micro-polluted water. A Box-Behnken response surface methodology was utilized to investigate the effect of operating conditions (dye concentration, agitation speed, carbon nanotubes dosage, Transmembrane Pressure and pH) on the dye removal and flux. The response surface methodology with high coefficients of determination values were fitted to the experimental data, which demonstrated that the polynomial response models fitted well for describing dye removal and adsorptive dynamic membrane filtration efficiency. Based on the design, the optimized conditions for obtaining highest dye removal rate (100%) were dye concentration = 5 mg/L, agitation speed = 210 rpm, carbon nanotubes dosage = 13 g/m 2 , Transmembrane Pressure = 0.2 mPa and pH = 5.8. The graphical optimization of superimposed contour plots fulfilled the conditions to obtain dye removal >95% and flux >100 L m −2 h −1 , as well the interactions among various operating conditions. The work indicated that response surface methodology can be applied for analyzing the effect of operating conditions and acquiring the optimized conditions for adsorptive dynamic membrane treating water/wastewater.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 108
·89015-89024
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IF 3.84
Yanqiu Pan,Wenjuan Wang,Wei Wang,Tonghua Wang
Theoretical and experimental investigations were conducted to predict particle deposition and layer growth during formation of a dynamic membrane using cross-flow microfiltration. A critical particle size model was developed and solved in radial, circumferential and axial directions by analyzing the forces acting on a single particle. The model accounted for the normal drag, lateral lift, shear-induced and Brownian diffusion forces in the depositional direction, the van der Waals force in the circumferential direction, and the cross-flow drag and van der Waals forces in the axial direction. Cross-flow velocity and feed temperature were selected as representative influencing factors to examine variations of the critical particle sizes with permeate flux. Experiments were then conducted with carbon tubes as the support and zirconium dioxide particles as the coating material to verify the model. Results showed that a dynamic layer with non-uniform thickness along the circumferential direction was formed within the horizontal tube due to gravity. The layer thickness decreased as the cross-flow velocities were increased under a given trans-membrane pressure difference and feed concentration. An appropriately large cross-flow velocity was beneficial to achieve thickness uniformity during formation. The effect of the feed temperature on the critical particle size and layer thickness can be ignored. Comparisons between the theoretical predictions and experimental data of the layer thicknesses displayed good agreements. The effects of trans-membrane pressure differences and feed concentrations were finally examined in the present work.
研究领域:
环境工程
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化学工程
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Yisong Hu,Ying Zang,Yuan Yang,Ao Duan,Xiaochang C. Wang,Huu Hao Ngo,Yu-You Li,Runda Du
Wastewater preconcentration to capture abundant organics is promising for facilitating subsequent anaerobic digestion (AD) to recover bioenergy, however research efforts are still needed to verify the effectiveness of such an emerging strategy as carbon capture plus AD. Therefore, lab-scale anaerobic dynamic membrane bioreactors (AnDMBRs) without and with the addition of zero-valent iron (ZVI) (i.e., AnDMBR1 versus AnDMBR2) were developed for preconcentrated domestic wastewater (PDW) treatment, and the impact of ZVI addition on process performance and associated mechanisms were investigated. The stepwise addition of ZVI from 2 to 4 to 6 g/L improved the treatment performance as COD removal slightly increased and TP removal and methane production were enhanced by 53.3%–62.9% and 22.6%–31.3%, respectively, in consecutive operational phases. However, the average increasing rate of the transmembrane pressure (TMP) in AnDMBR2 (0.18 kPa/d) was obviously higher than that in AnDMBR1 (0.05 kPa/d), indicating an unfavorable impact of dosing ZVI on the dynamic membrane (DM) filtration performance. ZVI that has transformed to iron ions (mainly Fe 2+ ) can behave as a coagulant, electron donor or inorganic foulant, thus enabling the excellent removal of dissolved phosphorous, enhancing the enrichment and activities of specific methanogens and causing the formation of a compact DM layer. Morphological, componential, and microbial community analyses provided new insights into the functional mechanisms of ZVI added to membrane-assisted anaerobic digesters, indicating that ZVI has the potential to improve bioenergy production and resource recovery, while optimizing the ZVI dosage should be considered to alleviate membrane fouling .
研究领域:
环境工程
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微生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）