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41.
湿法炼铜领域中的膜技术 总被引:8,自引:0,他引:8
结合典型应用实例,介绍用纳滤,反渗透,超滤,微滤,扩散渗析等膜分离解决铜溶剂萃取工艺中存在的低浓度含铜浸出液处理,水平衡控制与铜的浓缩,电解贫液处理,絮凝物等问题,并分析我国湿法炼铜工业中采用膜技术的前景。 相似文献
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Pei Sean Goh Kar Chun Wong Tuck Whye Wong Ahmad Fauzi Ismail 《Frontiers of Chemical Science and Engineering》2022,16(5):564
Polyamide thin film composite membranes have dominated current reverse osmosis market on account of their excellent separation performances compared to the integrally skinned counterparts. Despite their very promising separation performance, chlorine-induced degradation resulted from the susceptibility of polyamide toward chlorine attack has been regarded as the Achilles’s heel of polyamide thin film composite. The free chlorine species present during chlorine treatment can impair membrane performance through chlorination and depolymerization of the polyamide selective layer. From material point of view, a chemically stable membrane is crucial for the sustainable application of membrane separation process as it warrants a longer membrane lifespan and reduces the cost involved in membrane replacement. Various strategies, particularly those involved membrane material optimization and surface modifications, have been established to address this issue. This review discusses membrane degradation by free chlorine attack and its correlation with the surface chemistry of polyamide. The advancement in the development of chlorine resistant polyamide thin film composite membranes is reviewed based on the state-of-the-art surface modifications and tailoring approaches which include the in situ and post-fabrication membrane modifications using a broad range of functional materials. The challenges and future directions in this field are also highlighted. 相似文献
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The progress in atom transfer radical polymerization (ATRP) provides an effective means for the design and preparation of functional membranes. Polymeric membranes with different macromolecular architectures applied in fuel cells, including block and graft copolymers are conveniently prepared via ATRP. Moreover, ATRP has also been widely used to introduce functionality onto the membrane surface to enhance its use in specific applications, such as antifouling, stimuli-responsive, adsorption function and pervaporation. In this review, the recent design and synthesis of advanced functional membranes via the ATRP technique are discussed in detail and their especial advantages are highlighted by selected examples extract the principles for preparation or modification of membranes using the ATRP methodology. 相似文献
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Aiming at preparing high-performance polyamide (PA) reverse osmosis (RO) membrane in a facile and high effective way, the codeposition strategy of dopamine and zwitterionic polymer was first applied to modify PA RO membrane. The noncovalent bonds between dopamine and Poly [2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (PSPE) act to fix PSPE onto the membrane surface and simultaneously destroy the interaction force between dopamine aggregations so that the modified layer could equably form on the PA layer. PSPE significantly improved the hydrophilicity [the water contact angle (WCA) of S-D-3 is 25.3°] of the modified membrane. And, the smoother surface was noticed on the modified membrane. All of these endow the PSPE/dopamine modified membrane superb water flux (the maximum water flux is 51.86 L m−1 h−1 at 1.6 MPa and 25 °C) and impressive antifouling and anti-adhesion properties to bovine serum albumin (BSA) (protein), sodium dodecyl sulfate (anionic surfactant), and dodecyl trimethyl ammonium bromide (cationic surfactant) with salt retention was well maintained. Notably, in the BSA fouling test, nearly 100% of the flux recovery ratio was achieved. This method is promising to be employed in industrial scale-up production. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48355. 相似文献
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针对安钢永通铸管公司380m3高炉冷却系统存在的风口烧穿、热风阀烧坏、冷却壁结垢堵塞严重及个别模块烧毁等问题进行了分析,介绍了循环冷却系统完善、处理方案和相应的改进措施,以及改造后的运行效果. 相似文献
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反渗透专用阻垢剂性能的动态评价方法 总被引:2,自引:0,他引:2
综述了近年来反渗透专用阻垢剂的动态评价方法,包括给水一次通过法、全循环法、部分循环法、间歇循环法。从运行过程中溶液浓度的变化、化学药品的消耗量、模拟停留时间、结垢的种类等几方面对这4种评价方法进行了分析和比较,总结了各种方法的优缺点和适用范围,为人们选择和开发合适的阻垢剂评价方法提供了可靠的依据。 相似文献
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