Wu Daoji, Zhou Weiwei, Cheng Xiaoxiang, Luo Congwei, Li Peijie, Zhang Fengzhi, Ren Zixiao
School of Municipal and Environmental Engineering, Shandong Jianzhu University Jinan Shandong China 250101
Shandong Urban Construction Vocational College Jinan Shandong China 250103.
RSC Adv. 2019 Jun 27;9(35):20035-20043. doi: 10.1039/c9ra03549d. eCollection 2019 Jun 25.
In the present study, polyoxyethylene (20) sorbitan monolaurate (Tween-20) was employed as a surface coating agent for hydrophilic modification of poly(vinylidene fluoride) microfiltration membranes. The optimized parameters for membrane preparation (, coating temperature, coating concentration, coating time and drying time) were systematically investigated. Contact angle and transmembrane pressure were employed to evaluate the efficiency of the modified membranes, and the optimized parameters were proposed. The removal of chemical oxygen demand (COD) and suspended solids (SS), as well as fouling control performance, was further evaluated. The results showed that the optimized parameters were 40 °C, 4.5 mmol L, 45 min and 45 min for coating temperature, coating concentration, coating time and drying time, respectively. Under these conditions, a hydration layer on the surface was formed, resulting in a more hydrophilic membrane surface. During domestic wastewater treatment in membrane bioreactor (MBR), the Tween-20 modified membrane exhibited better performance with rejection efficiencies of 94.56% and 97.53% for COD and SS, respectively. Tween-20 coating could mitigate the increase of transmembrane pressure and reduce the concentration of proteins accumulated on the membrane surface, which was effective for membrane fouling control. Simultaneously, the operation time of MBR was extended from 25 to 46 days. Furthermore, the stability of Tween-20 coated PVDF membrane was also verified. The results indicated that surface coating with Tween-20 is efficient and easy to be carried out, showing a great potential for application in MBR during wastewater treatment.
在本研究中,聚氧乙烯(20)山梨醇酐单月桂酸酯(吐温 - 20)被用作聚偏氟乙烯微滤膜亲水化改性的表面涂层剂。系统研究了膜制备的优化参数(涂层温度、涂层浓度、涂层时间和干燥时间)。采用接触角和跨膜压力来评估改性膜的效率,并提出了优化参数。进一步评估了化学需氧量(COD)和悬浮固体(SS)的去除率以及抗污染性能。结果表明,涂层温度、涂层浓度、涂层时间和干燥时间的优化参数分别为40℃、4.5 mmol/L、45分钟和45分钟。在这些条件下,膜表面形成了水化层,从而使膜表面更具亲水性。在膜生物反应器(MBR)处理生活污水过程中,吐温 - 20改性膜表现出更好的性能,对COD和SS的截留效率分别为94.56%和97.53%。吐温 - 20涂层可以减轻跨膜压力的增加,并降低膜表面积累的蛋白质浓度,这对控制膜污染有效。同时,MBR的运行时间从25天延长到了46天。此外,还验证了吐温 - 20涂层PVDF膜的稳定性。结果表明,用吐温 - 20进行表面涂层高效且易于实施,在污水处理的MBR中具有很大的应用潜力。