Chen Anwen, Liu Wei, Soomro Razium Ali, Wei Yi, Zhu Xun, Qiao Ning, Kang Yueqi, Xu Bin
Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing, 100029, China.
State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China.
Environ Sci Pollut Res Int. 2022 Dec;29(56):84410-84420. doi: 10.1007/s11356-022-20810-0. Epub 2022 Jul 2.
Graphene oxide (GO) is an excellent membrane-forming material with unique two-dimensional transport channels and excellent adsorption properties for heavy metal contaminants. However, swelling under cross-flow conditions and long-term water immersion leads to poor separation performances. To improve the stability of GO membrane materials, we propose a PVA-integrated graphene oxide/attapulgite membrane (GOAP) with a 3D microstructural arrangement of "brick-mortar-brick." The addition of PVA as mortar reinforces the strength of the structures via induced hydrogen bonding within the 3D water transport network. Furthermore, the AlO ceramic substrate pre-treated with (3-aminopropyl) triethoxysilane (APTES) provided high mechanical stability to the composite membrane, extending the membrane's stability beyond a month of immersion without swelling or shedding. The PVA-integrated GO/ATP composite membrane maintained a rejection rate of 99% for Cu solution (100 mg/L) in a 26-h continuous with nearly 100% rejection for various metals ions such as Cu, Ni, Pb, and Cd. The membrane exhibited a water flux of 20.7 L·m·h, which was 15.9-fold high than the pure GO membrane (GOM). The high water flux and heavy metal filtration rate with superior stability proved the practical suitability of the composite film for removing heavy metal ions.
氧化石墨烯（GO）是一种优异的成膜材料，具有独特的二维传输通道以及对重金属污染物出色的吸附性能。然而，错流条件下的溶胀以及长期水浸会导致分离性能不佳。为提高GO膜材料的稳定性，我们提出了一种具有“砖-灰浆-砖”三维微观结构排列的聚乙烯醇复合氧化石墨烯/凹凸棒石膜（GOAP）。作为灰浆添加的聚乙烯醇通过在三维水传输网络内诱导形成氢键增强了结构强度。此外，用（3-氨丙基）三乙氧基硅烷（APTES）预处理的AlO陶瓷基底为复合膜提供了高机械稳定性，使膜在浸泡一个多月后仍保持稳定，无溶胀或脱落现象。聚乙烯醇复合GO/ATP膜在连续26小时内对铜溶液（100mg/L）的截留率保持在99%，对铜、镍、铅和镉等各种金属离子的截留率接近100%。该膜的水通量为20.7L·m·h，比纯氧化石墨烯膜（GOM）高15.9倍。高水通量和重金属过滤率以及卓越的稳定性证明了该复合膜在去除重金属离子方面的实际适用性。
