Atian Xie,Jiuyun Cui,Jin Yang,Chunxiang Li,Yi Wang,Jiangdong Dai
The effective treatment of oily wastewater is of great significance for the protection of the ecological environment and human health. Aiming to prepare a membrane with excellent antifouling properties, a new active antifouling carbon cloth@Ni-Co LDH/Ag (CC@LDH/Ag) membrane was reported here via in situ hydrothermal growth and followed photo-deposition methods. The effects of Ag deposition on self-cleaning ability and surface wettability of CC@LDH/Ag membrane were studied. The experimental results showed CC@LDH/Ag membrane is superhydrophilic/underwater superoleophobic, and exhibited high separation efficiency (>98.6%) and high flux (6551–22,050 L m −2 h −1 ) for different kinds of oil/water mixtures. Moreover, CC@LDH/Ag membrane also displayed excellent environmental and mechanical durability. Good self-cleaning ability enabled CC@LDH/Ag membrane to be separated at least 30 times, and still maintained high separation performance. The self-cleaning CC@LDH/Ag membrane may hold great application prospects in oily wastewater remediation.
Yufei Wang,Zili Liu,Xingchuan Wei,Kuiliang Liu,Jiahai Wang,Jietao Hu,Jing Lin
Numerous strategies on the application of superwettable membranes for oil/water (O/W) separation have been proposed; however, few works on one-step separation strategies and the separation mechanism of complex O/W effluents containing organic dye and bacteria have been reported. Here, an integrated strategy for O/W separation, removal, and anti-oil/bacteria/dye-fouling is firstly proposed. A hydrogel fabricated PVDF@ZnO/Ag (H-PVDF@ZnO/Ag) membrane is designed with a superhydrophilic/underwater superoleophobic surface and hierarchical membrane channels, which exhibits superior separation efficiency (99.4%) and flux (1700 L m −2 h −1 bar −1 ). Considering the wettability, the interface intrusion pressure influences the O/W separation. Also considering the energy and molecular kinetics, the differences in the interaction energy and mean square displacement (MSD) of the water and oil molecules with the membrane obtained by molecular dynamics (MD) simulations are the internal factors influencing the O/W separation. The experimental and MD simulation results demonstrate that the high organic dye removal efficiency (>99%) is attributed to the synergistic effect between the hydrogel electrostatic adsorption and the ZnO/Ag photodegradation. The excellent anti-oil/dye/bacteria-fouling is due to the low oil adhesion, hydration layer, photodegradation, and antibacterial activity. Introducing an amino resin to the membrane increases the membrane’s tolerance and resistance to mechanical damage and chemical attack due to the intertwined cross-linking network and hydrogen bonds. The membrane also exhibits effective separation of real wastewater from jeans factory. This strategy may inspire further research on the treatment of complex O/W effluents.
Water is a precious resource in space stations, and wastewater recycling is necessary to meet the needs of astronauts. In that respect, applying the high anti-pollution disk tubular reverse osmosis (DTRO) technique is a reliable way to remove pollutes from wastewater. Thin film composite (TFC) membrane treatment is the most frequently employed solution for purifying wastewater in industry; however, the intrinsic weaknesses of polymer membrane substrates, e.g., poor mechanical property, foulant adsorption and low resistance to acidic/basic conditions, greatly hamper their applications. In this study, the novel polysulfate (PSE) membrane substrates were prepared via non-solvent induced phase separation (NIPS) method. The microstructure and performance of PSE membrane substrates were comprehensively investigated at varying polymer concentration and nanoparticle types. The results showed that adding nanosilver to the support layer significantly enhanced the TFC- PSE/Ag membrane performance (up to 57 %) and tensile strength (by 4.57 ± 0.13). According to computational fluid dynamics (CFD) simulations, the optimized geometric design of deflectors would have noticeably improved the flow field distribution and strength, which was consistent with experimental data. The DTRO modules enabled the effective management of wastewater using simulated space bathing wastewater. The effluent met the water reuse criteria in terms of COD concentration, NH 3 -N concentration, conductivity and turbidity whose respective values were 15 mg/L, 0.21 mg/L, 60 μS/cm, and 0.9 NTU. The proposed DTRO modules own antifouling and acid/alkaline-resistance, indicating their remarkable application potential in the large-scale recovery of bathing wastewater from the earth or space station.
危险品化学品经营许可证（带存储）