Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea.
Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea; KU-KIST Green School, Graduate School of Energy and Environment, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
Chemosphere. 2018 Sep;207:347-356. doi: 10.1016/j.chemosphere.2018.05.096. Epub 2018 May 17.
Graphene oxide (GO)/poly(vinylidene fluoride) (PVDF) electrospun nanofibrous membranes (ENMs) have been fabricated to remove tetracycline (TC) from water via adsorptive-filtration. The pure water permeation flux of GO/PVDF ENMs (27,407-29,337 LMH/bar) was increased compared with that of PVDF ENMs. The flow pore diameter was steadily reduced by increasing the GO content from 0 to 1.5 wt% in the GO/PVDF ENMs. The maximum TC adsorption capacity of GO is 720.26 mg/g (Langmuir model) and GO retained its TC adsorption property after incorporation into GO/PVDF ENMs during water filtration (transmembrane pressure = 0.91 bar). The maximum experimental TC removal capacity (q,) was 17.92 mg/g with 1.5 wt% of GO (GO/PVDF) ENMs, which was similar to the modified dose-response model value of 18.03 mg/g. In the presence of natural organic matter, TC adsorption was enhanced, because hydrophobic organic carbon improved hydrophobic and π-π interactions. The presence of Cu(II) further improved the TC adsorption capacity of GO/PVDF ENMs through cation bridging. However, the presence of Ca(II) hindered TC adsorption by an electron shielding effect. For examining anti-fouling activity of GO/PVDF ENMs, the log removal values of both bacteria, Escherichia coli and Staphylococcus aureus, were maintained at over 5 during water filtration. In addition, incorporation of GO in PVDF ENMs prevents bovine serum albumin (BSA) adsorption by both increasing the hydrophilicity of the ENMs forming hydration layer on the surface and electrostatic repulsion between both negatively charged BSA and GO in GO/PVDF ENMs (zeta potential = - 14.14 mV, deionized water at pH 6).
氧化石墨烯（GO）/聚偏二氟乙烯（PVDF）静电纺纳米纤维膜（ENMs）已被制备用于通过吸附-过滤从水中去除四环素（TC）。与 PVDF ENMs 相比，GO/PVDF ENMs 的纯水渗透通量（27,407-29,337 LMH/bar）增加。通过在 GO/PVDF ENMs 中从 0 到 1.5 wt%增加 GO 的含量，流孔直径稳步减小。GO 的最大 TC 吸附容量为 720.26 mg/g（朗缪尔模型），并且在水过滤过程中（跨膜压力= 0.91 巴）GO 保留了其 TC 吸附性能。在 1.5 wt%GO（GO/PVDF）ENMs 中，最大实验 TC 去除容量（q，）为 17.92 mg/g，与修正后的剂量响应模型值 18.03 mg/g 相似。在天然有机物存在下，TC 吸附增强，因为疏水性有机碳改善了疏水性和 π-π 相互作用。Cu(II) 的存在通过阳离子桥接进一步提高了 GO/PVDF ENMs 的 TC 吸附能力。然而，Ca(II)的存在通过电子屏蔽效应阻碍了 TC 的吸附。为了检验 GO/PVDF ENMs 的抗污活性，在水过滤过程中，两种细菌（大肠杆菌和金黄色葡萄球菌）的对数去除值均保持在 5 以上。此外，通过增加 ENMs 的亲水性，在 ENMs 表面形成水合层，以及 GO/PVDF ENMs 中带负电荷的 BSA 和 GO 之间的静电排斥，GO 的掺入防止了牛血清白蛋白（BSA）的吸附（Zeta 电位=-14.14 mV，pH 6 的去离子水）。
