Zhou Kai, Guo Changsheng, Gan Feng, Xin John H, Yu Hui
Guangdong-Hong Kong Joint Laboratory for Advanced Textile Materials, School of Textile Materials and Engineering, Wuyi University, Jiangmen 529020, China.
Institute of Textiles & Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
J Colloid Interface Sci. 2023 Jun 15;640:261-269. doi: 10.1016/j.jcis.2023.02.107. Epub 2023 Feb 24.
In existing separation membranes, it is difficult to quickly produce large-area graphene oxide (GO) nanofiltration membranes with high permeability and high rejection, which is the bottleneck of industrialization. In this study, a pre-crosslinking rod-coating technique is reported. A GO-P-Phenylenediamine (PPD) suspension was obtained by chemically crosslinking GO and PPD for 180 min. After scraping and coating with a Mayer rod, the ultra-thin GO-PPD nanofiltration membrane with an area of 400 cm and a thickness of 40 nm was prepared in 30 s. The PPD formed an amide bond with GO to improve its stability. It also increased the layer spacing of GO membrane, which could improve the permeability. The prepared GO nanofiltration membrane had a 99 % rejection rate for dyes such as methylene blue, crystal violet, and Congo red. Meanwhile, the permeation flux reached to 42 LMH/bar, which was 10 times that of the GO membrane without PPD crosslinking, and it still maintained excellent stability under strongly acidic and basic conditions. This work successfully solved the problems of GO nanofiltration membranes, including the large-area fabrication, high permeability and high rejection.
在现有的分离膜中，难以快速制备出具有高渗透性和高截留率的大面积氧化石墨烯（GO）纳滤膜，这是其工业化的瓶颈。在本研究中，报道了一种预交联棒涂技术。通过将GO与对苯二胺（PPD）化学交联180分钟，得到GO-PPD悬浮液。用迈耶棒刮涂后，在30秒内制备出面积为400平方厘米、厚度为40纳米的超薄GO-PPD纳滤膜。PPD与GO形成酰胺键以提高其稳定性。它还增加了GO膜的层间距，从而提高了渗透性。所制备的GO纳滤膜对亚甲基蓝、结晶紫和刚果红等染料的截留率达到99%。同时，渗透通量达到42 LMH/bar，是未进行PPD交联的GO膜的10倍，并且在强酸性和碱性条件下仍保持优异的稳定性。这项工作成功解决了GO纳滤膜的大面积制备、高渗透性和高截留率等问题。
