Anike Obinna, Cuhorka Jiří, Ezeogu Nkechi, Mikulášek Petr
Institute of Environmental and Chemical Engineering, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 532 10 Pardubice, Czech Republic.
Membranes (Basel). 2024 Nov 23;14(12):248. doi: 10.3390/membranes14120248.
The widespread use of antimicrobial drugs has contributed to the increasing trace levels of contaminants in the environment, posing an environmental problem and a challenge to modern-day medicine seeking advanced solutions. Nanofiltration is one such breakthrough solution for the selective removal of antibiotics from wastewater due to their high efficiency, scalability, and versatility. This study examines the separation of antibiotics (sulfamethoxazole (SMX), trimethoprim (TMP), and metformin (MET), respectively) using commercially available membranes with an emphasis on AFC membranes (AFC 30 and AFC 80). Thus, we evaluate their efficacy, performance, and applicability in wastewater treatment processes. The data for characterizing the structural parameters of the NF membranes were determined from an uncharged organic solute rejection experiment, and the effect of various operating conditions on the retention of solutes was evaluated. All experimental data were collected using a laboratory-scale nanofiltration unit and HPLC, and rejection percentages were determined using analytical measurements. The results obtained allowed for the determination of the radius of the membrane pores using the Steric Hindrance Pore (SHP) model, resulting in values of 0.353 and 0.268 nm for the AFC 30 and AFC 80 membranes, respectively. Additionally, higher transmembrane pressure and feed flow were observed to lead to an increased rejection of antibiotics. AFC 30 demonstrated a rejection of 94% for SMX, 87% for TMP, and 87% for MET, while AFC 80 exhibited a rejection of 99.5% for SMX, 97.5% for TMP, and 98% for MET. The sieving effect appears to be the primary separation mechanism for AFC 30, as lower feed-flow rates were observed to intensify concentration polarization, thereby compromising rejection efficiency. On the contrary, AFC 80 experienced less concentration polarization due to its smaller pore sizes, effectively preventing pore clogging. Membrane performance was evaluated using the Spiegler-Kedem-Katchalsky model, based on irreversible thermodynamics, which effectively explained the mechanism of solute transport of antibiotics through the AFC 30 and AFC 80 membranes in the NF process.
抗菌药物的广泛使用导致环境中污染物的痕量水平不断增加，这既带来了环境问题，也给寻求先进解决方案的现代医学带来了挑战。纳滤是一种突破性的解决方案，因其高效、可扩展性和多功能性，能够从废水中选择性去除抗生素。本研究考察了使用市售膜（重点是AFC膜（AFC 30和AFC 80））分离抗生素（分别为磺胺甲恶唑（SMX）、甲氧苄啶（TMP）和二甲双胍（MET））的情况。因此，我们评估了它们在废水处理过程中的功效、性能和适用性。通过非带电有机溶质截留实验确定了纳滤膜结构参数的数据，并评估了各种操作条件对溶质截留率的影响。所有实验数据均使用实验室规模的纳滤装置和高效液相色谱法收集，并通过分析测量确定截留率。所得结果允许使用空间位阻孔（SHP）模型确定膜孔半径，AFC 30膜和AFC 80膜的半径分别为0.353和0.268纳米。此外，观察到较高的跨膜压力和进料流量会导致抗生素截留率增加。AFC 30对SMX的截留率为94%，对TMP的截留率为87%，对MET的截留率为87%，而AFC 80对SMX的截留率为99.5%，对TMP的截留率为97.5%，对MET的截留率为98%。筛分效应似乎是AFC 30的主要分离机制，因为观察到较低的进料流速会加剧浓差极化，从而损害截留效率。相反，AFC 80由于其较小的孔径，浓差极化较小，有效防止了膜孔堵塞。基于不可逆热力学，使用Spiegler-Kedem-Katchalsky模型评估了膜性能，该模型有效地解释了纳滤过程中抗生素通过AFC 30和AFC 80膜的溶质传输机制。
