SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Pengbo Zhao,Bowen Yao,Junquan Meng,Rui Zhang,Bing Cao,Pei Li
Pervaporation (PV), as a cost-efficient concentrating process, has been studied for Zero Liquid Discharge (ZLD) of desalination. Although high water flux and excellent salt rejection have been reported for many PV membranes. The desalination performance, fouling behavior, and cleaning protocol for treating real reverse osmosis concentrate (ROC) generated from industrial plants have never been studied. Meanwhile, understanding the fouling behavior and cleaning method in the treating process is crucial for the development of suitable PV desalination membranes. In this study, we used a lab-made PV membrane to treat industrial ROC with a high chemical oxygen demand (COD) value and high salt concentrations. The results showed that conductivity and COD of the produced water were below 20 μs/cm and 70 mg/L, respectively, which fulfilled the discharge standard. However, the membrane fouling problem was not trivial. To address the fouling issue, a chemical softening method was adopted to remove the calcium salts of the ROC, and a membrane cleaning method was developed to regenerate the water flux. As a result, a long-term water flux of 31.27 kg/m 2 ·h with a flux recovery rate of 98% were realized. This highlights the potential of PV desalination technology for ROC reclamation.
研究领域:
环境科学
·
材料科学
·
水处理工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2014
·
IF 2.538
Hong Meng,Qiang Cheng,Chunxi Li
The adhesion of proteins to the surface and pores of ultrafiltration membrane is one of the most important causes of membrane fouling, consequently lead to deterioration of membrane performance. In the present study, a polyacrylonitrile (PAN)-based zwitterionic ultrafiltration membrane was developed to improve its anti-protein-fouling capacity. 3-Dimethylaminopropylamine was first grafted onto the hydrolyzed PAN membrane by activation. Subsequently, carboxylic zwitterions were produced on the membrane surface by quaternization with 3-bromopropionic acid. The zwitterionic membranes were rigorously characterized in terms of chemical composition, morphology, and surface properties indicating that the zwitterion could successfully be bonded onto the PAN membrane without having significant effects on the membrane morphology. The anti-protein-fouling properties of the membrane were tested using static protein adsorption and dynamic-filtration experiments. The experimental results show that, although the hydrophilicity of the zwitterionic membrane decreased, the flux recovery rate of the zwitterion-grafted membrane was much higher than that of the hydrolyzed PAN membrane. Therefore, the formation of zwitterionic hydration layer may effectively prevent the adsorption interaction between protein and membrane surface, which is beneficial for the improvement of the anti-protein-fouling capacity.
研究领域:
材料科学
·
膜科学与技术
·
生物医学工程
·
表面化学
·
分离科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yong Chen,Tao Wan,Yanjun Huang,Yi Wang,Guozhi Fan,Lei Zhang,Shengxuan Fan,Xueling Liu
The amount of substation accident oil pool wastewater (SAOPW) generated has been increasing due to the successive addition and renovation of substations, and the discharge of untreated or incomplete treatment outside the station will cause serious environmental pollution problems. In this study, a polyethersulfone (PES) composite ultrafiltration membranes were fabricated using phase inversion method and evaluated them for oil removal from SAOPW. The morphology and functional groups of PES composite membranes before and after filtration were characterized and compared through scanning electron microscopy and Fourier-transform infrared spectroscopy. The effects of operating pressure, feed temperature, initial oil concentration and operating time were systematically investigated using flux recovery and oil removal rate as the indexes of investigation, and the process economy was studied and evaluated. The results showed that the PES composite membrane had a relatively high-water flux of 260.2 (L·m –2 ·h –1 ) and a high oil removal rate (≥90%), which could effectively remove oil from water. Besides, its high flux recovery ratio (≥90%) after four filtration and cleaning cycles indicated the excellent performance of this PES composite membrane in the separation of oil–water emulsions. This study confirms the applicability of PES composite membrane for oil removal from SAOPW, providing a promising treatment method for the SAOPW treatment.
研究领域:
环境工程
·
膜技术
·
水处理
·
化学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Zhaofeng Wang,Panyi Chen,Yang Liu,Hanxiang Guo,Nan Sun,Qiqi Cai,Yueying Yu,Fangbo Zhao
In this study, a new kind of aromatic diamine monomer named as 1,4-bis(4-aminophenyl)piperazine (BANPZ) was particularly designed and synthesized, and then the novel zwitterionic polyimide (ZPI) was prepared through a two-step process including polycondensation and quaternary amination reaction. The chemical structures of the prepared monomer and polymers were identified by FTIR and 1 H NMR measurements, respectively. Meanwhile, the inherent viscosities, molecular weights, solubility behaviors and thermal properties of two obtained polymers were thoroughly characterized. Compared with the control polyimide (PI) membrane, the presence of zwitterionic groups considerably improve the hydrophilicity of the ZPI membrane, thereby enhancing the water permeability to some extent without obviously affecting the rejection ratio. Based on the static protein adsorption and dynamic cycle ultrafiltration experiments, the ZPI membrane exhibited persistent antifouling property, which was demonstrated by the flux decline ratio and filtration resistance. In particular, the water flux recovery ratio of the ZPI membrane was retained at 96.0% after a three-cycles of BSA solution filtration, which was much higher than that of the PI membrane (76.7%), suggesting excellent long-term performance stability. This new approach provided a valuable strategy of combining polymer chemical structure optimization and mature non-solvent induced phase separation (NIPS) method, which could greatly drive the development and application range of separation membranes.
研究领域:
材料科学
·
膜技术
·
聚合物化学
✓ 已验证
DOI
高影响因子
WATER SCIENCE AND TECHNOLOGY
·
2021
·Vol. 84
·期 12
·3576-3585
·
IF 1.915
Shen Chong,Zhang Qian,Meng Qin
Ultrafiltration membranes can intercept oil particles smaller than 10 μm, but the membranes are easily contaminated by oil due to their hydrophobicity. To treat various oily wastewaters, we prepared a hydrophilic hollow fiber membrane (HFM) with anti-fouling property by grafting sulfobetaine methacrylate (SBMA) onto polysulfone (PSU). For six simulated wastewaters containing emulsified oil at 1,000 mg/L, the PSU-g-SBMA HFM was able to remove 98.5–99.7% of oil, higher than that of PSU HFM at 91.1–98.9%. The oil concentration in filtrate was less than 15 mg/L, which could meet the discharge standard of wastewater. The water flux of PSU-g-SBMA HFM can be completely recovered after being washed by rhamnolipid and alkali solution, while the same cleaning process could not recover the PSU HFM. As found, the contact angles of oil droplets on the PSU-g-SBMA membrane were larger than those on PSU membrane, which indicated the improved hydrophilicity by PSU-g-SBMA. For 48 h of filtration to soybean and diesel oil/water emulsion, the effect of PSU-g-SBMA HFM was stable and the flux could be completely recovered by cleaning. Therefore, we provided a new method for oily wastewater treatment, which can efficiently and energy-saving remove various oil substances in wastewater. PSU-g-SBMA hollow fiber membrane could well remove >98.5% of various oil form wastewaters. RHA + NaOH solution could completely recover the water flux of the oil-contaminated PSU-g-SBMA hollow fiber membrane. Oil contamination on membranes was partly determined by the contact angles of oil.
研究领域:
环境工程
·
膜技术
·
水处理
·
高分子科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）