Dolina Jan, Gončuková Zuzanna, Bobák Marek, Dvořák Lukáš
Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec Studentská 2 461 17 Liberec Czech Republic
Membrain s.r.o. Pod Vinicí 87, 471 27 Stráž pod Ralskem Czech Republic.
RSC Adv. 2018 Apr 18;8(26):14552-14560. doi: 10.1039/c8ra02026d. eCollection 2018 Apr 17.
Biofouling represents a serious problem limiting the widespread application of membrane technology. Therefore, the aim of this study was to develop and verify a new modification method based on the formation of silver nanoparticles and their incorporation into a membrane polymer to prevent biofouling. The modification method consisted of soaking a commercial hollow-fibre polyethersulfone membrane in a solution of silver ions, diffusion of ions into the membrane polymer, and their reduction using ascorbic acid. Such a modified membrane displayed a lower tendency towards biofouling, exhibiting an about 15% higher permeability compared to an unmodified membrane when filtering actual wastewater treatment plant effluent. The modification also led to the formation of stable silver nanoparticles (mostly in the range of 25-50 nm) homogenously distributed on the surface of the hollow-fibres. This resulted in higher surface hydrophilicity (the water contact angle decreased from 91° to 86°) contributing to the biofouling prevention. The modified membrane also showed high stability, as only 2.1% of the total silver leached after 8 h of filtration. Moreover, no changes in the original membrane cross-section structure or separation properties were observed. Besides the improved antibiofouling properties of the modified membrane, the main advantage of the developed method is its simplicity, short reaction time, absence of high energy-consuming initiation, and the possibility to apply it on site, thus even with commercial membrane modules. It will increase the application potential of membranes in the field of wastewater treatment.
生物污染是限制膜技术广泛应用的一个严重问题。因此，本研究的目的是开发并验证一种基于银纳米颗粒的形成及其掺入膜聚合物以防止生物污染的新改性方法。该改性方法包括将商用中空纤维聚醚砜膜浸泡在银离子溶液中，使离子扩散到膜聚合物中，并用抗坏血酸将其还原。这种改性膜表现出较低的生物污染倾向，在过滤实际污水处理厂出水时，与未改性膜相比，渗透率高出约15%。改性还导致在中空纤维表面均匀分布形成稳定的银纳米颗粒（大多在25 - 50 nm范围内）。这导致表面亲水性提高（水接触角从91°降至86°），有助于防止生物污染。改性膜还表现出高稳定性，因为在过滤8小时后，总银的浸出量仅为2.1%。此外，未观察到原始膜横截面结构或分离性能的变化。除了改性膜的抗生物污染性能得到改善外，所开发方法的主要优点是其简单性、反应时间短、无需高能耗引发，并且有可能现场应用，甚至适用于商业膜组件。这将增加膜在废水处理领域的应用潜力。
