Although existing membrane filtration technologies offer practical solutions for the removal of heavy metal ions from wastewater, there remains a great need for the realization of a membrane simultaneously possessing excellent selectivity, high permeability, and antifouling capability. Towards this end, novel buckypaper (BP) membranes were fabricated from multi-walled carbon nanotubes (MWCNTs) via vacuum filtration technique and the capability of two biopolymers (i.e. chitosan and carrageenan) to facilitate the formation of aqueous dispersions of MWCNTs was investigated alone and in combination of each other. For the first time, this study shows that the combination of BP membrane and both biopolymers (MWCNTs/chitosan-carrageenan) performs remarkably in terms of mechanical properties and high rejection of heavy metals. At an applied pressure of one bar, the removal of copper and lead reached 94% and 91%, respectively. The MWCNTs/chitosan-carrageenan membrane was also found to be mechanically robust, with a tensile strength and Young’s modulus of 30.69 ± 2.6 MPa and 3.78 ± 0.03 GPa, respectively. However, the MWCNTs/chitosan membrane showed superior water permeate flux, reaching up to 180 L/h.m². The morphological properties and surface area (193 ± 3 to 285 ± 5 m²/g) of the three membrane types were also characterized using scanning electron microscopy and Brunauer, Emmett, and Teller analysis.

尽管现有的膜过滤技术为去除废水中的重金属离子提供了实用的解决方案，但仍然非常需要实现同时具有优异选择性、高渗透性和防污能力的膜。为此，通过真空过滤技术由多壁碳纳米管 (MWCNT) 制造了新型巴克纸 (BP) 膜，并单独研究了两种生物聚合物（即壳聚糖和角叉菜胶）促进 MWCNT 水分散体形成的能力，并相互结合。该研究首次表明，BP 膜与两种生物聚合物（MWCNTs/壳聚糖-角叉菜胶）的组合在机械性能和高重金属截留率方面表现出色。在 1 bar 的压力下，铜和铅的去除率分别达到 94% 和 91%。还发现 MWCNTs/壳聚糖-卡拉胶膜具有机械强度，拉伸强度和杨氏模量分别为 30.69 ± 2.6 MPa 和 3.78 ± 0.03 GPa。然而，MWCNTs/壳聚糖膜表现出优异的水渗透通量，高达180 L/hm² . 三种膜类型的形态特性和表面积（193 ± 3 至 285 ± 5 m ² /g）也使用扫描电子显微镜和布鲁诺、埃米特和泰勒分析进行了表征。