物理化学学报2020，Vol.36Issue(1)：83-91,9.DOI:10.3866/PKU.WHXB201906044
具有抗生物污染活性的分子筛膜用于高效油水分离
Zeolite-Coated Anti-Biofouling Mesh Film for Efficient Oil-Water Separation
摘要
Abstract
The development of the global economy has been accompanied by frequent oil spills caused by accidental leaks and industrial manufacturing, which have seriously threatened the aquatic environment and human health. Traditional methods for the treatment of oily wastewater include centrifugation, skimming, flotation, oil-absorbing technology, etc., which are limited by low separation efficiency as well as secondary pollution during the post-processing of oil absorption materials. Recently, separation technologies utilizing the special wettabilities of filtration membranes have been developed to enrich and recycle oils from wastewater. Among these, the fabrication of superhydrophilic/underwater superhydrophobic membranes have attracted intensive research interest, which can selectively allow the passage of water through the membrane while blocking the oils. However, microorganisms are more likely to breed on these hydrophilic surfaces, eventually leading to the blockage of the membranes. In this study, ZSM-5 zeolite crystals (MFI topological structure) were coated onto the stainless-steel meshes by means of seeding and secondary hydrothermal growth. Then, 70% of the total Na+ ions in the zeolite channels were substituted by Ag+ ions via an ion exchange process. The resultant membranes (Ag@ZCMFs) were superamphiphilic in air, with both water contact angle and oil contact angle of approximately 0°. However, they became superoleophobic when immersed in water, and the underwater oil contact angle reached 151.27° ± 4.34°. In terms of special wettability, Ag@ZCMF achieved efficient separation for various oil-water mixtures with separation efficiencies above 99%. The water flux and intrusion pressure of Ag@ZCMF depended on the diameter of pinholes in the membrane, which could be modulated by altering the time of secondary hydrothermal growth. For instance, the average diameter of pinholes in Ag@ZCMF with optimum secondary growth time of 14 h (Ag@ZCMF- 14) reached approximately 21 μm, giving rise to the water flux and intrusion pressure of 54720 L·m?2·h?1 and 4357 Pa, respectively. The anti-corrosion test and rubbing test confirmed the high chemical and mechanical stability of Ag@ZCMF- 14, respectively. The separation efficiency of Ag@ZCMF-14 remained stable during ten purification?regeneration cycles, and no obvious attenuation was observed, proving the high separation stability of Ag@ZCMF-14. Furthermore, the loaded Ag+ ions afforded the membrane excellent anti-biofouling activity, which could effectively inhibit the growth of both alga and bacteria in the operating environment, thus preventing membrane blockage during the oil-water separation process. In particular, the bacteriostatic rate of Ag@ZCMF-14 to Escherichia coli reached to 99.6%. These results demonstrate that Ag@ZCMFs with anti-biofouling activity has promising potential future applications in the removal of oil slicks from oily wastewater.关键词
分子筛/浸润性/油水分离/离子交换/抗生物污染Key words
Zeolite/ Wettability/ Oil-water separation/ Ion exchange/ Anti-biofouling activity分类
化学化工引用本文复制引用
王百先,王琪菲,邸建城,于吉红..具有抗生物污染活性的分子筛膜用于高效油水分离[J].物理化学学报,2020,36(1):83-91,9.基金项目
国家自然科学基金(21621001,21835002),111 计划(B17020)和吉林省/吉林大学新材料合作建设项目资金(SXGJSF2017-3)资助.The project was supported by the National Natural Science Foundation of China (21621001, 21835002), the 111 Project, China (B17020) and the Jilin Province/Jilin University Co-construction Project-Funds for New Materials, China (SXGJSF2017-3). （21621001,21835002）
