Rational Process Design for Facile Fabrication of Dual Functional Hybrid Membrane of MOF and Electrospun Nanofiber towards High Removal Efficiency of PM 2.5 and Toxic Gases

Dual antifouling and antibacterial polysulfone(PSf)/polyethersulfone(PES) hybrid membranes were developed by the synergy of capsaicin-mimic N-(5-methyl acrylamide-2,3,4 hydroxy benzyl) acrylamide (AMTHBA) and vinyl triethylene (b-methoxy ethoxy) silane (VTMES). First, AMTHBA as a natural antimicrobial agent was incorporated into a casting solution via “microwave-assistance (MWA) in situ polymerization-blending” process to construct a hydroxyl-rich environment. Then, VTMES crosslinked to a hydroxyl-rich polymer matrix via hydrolytic condensation, and the influence of VTMES content on the hybrid membrane properties was systematically investigated. When the VTMES added amount was 1.0 wt %, the hybrid membrane achieved an optimal separation performance including a steady-state humic acid (HA) (5 mg/L) permeation flux of 326 L·m−2·h−1 and a rejection percentage of 97%. The antibacterial tests revealed that the hybrid membranes exhibited sustained bactericidal activity and effective inhibition of bacterial adhesion. Besides, the dual-functional membranes were clean as new after two-cycles filtration (with a cleaning efficiency of ~90%), indicating that the network silicone film on the surface benefits the foulant repellence. Hopefully, the dual-functional membranes constructed in this study can be applicable to the pretreatment stage of water treatment.

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Evaluation of modified permeable pavement systems with coal gangue to remove typical runoff pollutants under simulated rainfall

Water Science & Technology ◽

10.2166/wst.2020.574 ◽

2020 ◽

Author(s):

Xiaoran Zhang ◽

Yiran Tian ◽

Junfeng Liu ◽

Yinrui Wang ◽

Ziyang Zhang ◽

...

Keyword(s):

Removal Efficiency ◽

Process Design ◽

Coal Gangue ◽

Maximum Adsorption Capacity ◽

Batch Experiments ◽

Leaching Behavior ◽

Permeable Pavement ◽

Traditional System ◽

Sorption Ability ◽

Sand And Gravel

Abstract Coal gangue (CG) as mineral waste was properly treated and applied as the filter media in permeable pavement systems due to its good sorption ability and mechanical strength. Batch experiments show the maximum adsorption capacity of calcined CG to phosphorus could reach 2.63 mg/g. To evaluate the removal effect of typical runoff pollutants including COD, TN, TP and NH4+-N, the gravel and sand in a traditional pavement system were replaced by CG respectively. The leaching behavior of the four pollutants in CG modified systems is limited and comparable with traditional system, indicating pretreated CG as filler would not cause environmental risk. CG-based pavement systems improved the removal efficiency of the four pollutants especially for TP. The removal mechanisms including interception, adsorption and microorganism degradation. The removal rates of COD, NH4+-N and TN by CG modified and traditional systems decreased with rainfall duration, while it is not obviously changed with rainfall recurrence period and drying period. Overall, the permeable pavement with CG layers that replaced both sand and gravel layers show best removal efficiency of all pollutants investigated especially for TP (>95%). This study provides a new way for CG utilization and gives the reference for the process design of permeable pavement.

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Study on Nitrogen Removal Efficiency of Hybrid Anoxic/Aerobic Membrane Bioreactor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.516 ◽

2012 ◽

Vol 178-181 ◽

pp. 516-519

Author(s):

Bai Ge Su ◽

Zhi Qiang Liu ◽

Xiao Jing Li ◽

Xue Xu ◽

Lei Gao

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Hybrid Membrane ◽

Filling Ratio ◽

Experimental Results ◽

Aeration Intensity ◽

System A ◽

Bioreactor System ◽

Main Influence

Based on fillers theory and traditional A/O-MBR theory, anoxic/aerobic hybrid membrane bioreactor system (A/O-HMBR for short) was modified by adding suspended biological fillers in one of the aerobic tanks of the traditional A/O-MBR, in which the filling ratio of fillers was 8%. The thesis mainly studies the nitrogen removal effect in the A/O-HMBR system when the main influence parameters, such as influent C/N(5,7,10), aeration intensity(15m3/h,20m3/h,25m3/h) and HRT(5h,8h,11h), were changed.The experimental results show that when HRT was 8h, C/N was 7, and aeration intensity was 20m3/h, TN removal effect was best.

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