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8256845 
Journal Article 
添加共试剂改善聚酰胺复合反渗透膜的性能 
Yan, T; Zhang, N; Li, Q; Li, Z; Li, C; Li, X; Yu, R; Wang, R; Wang, J; Cao, Z 
2021 
1 
Gaodeng Xuexiao Huaxue Xuebao / Chemical Journal of Chinese Universities
ISSN: 0251-0790 
Higher Education Press Limited Company 
42 
6 
2008-2014 
Chinese 
In a bid to improve the performance of polyamide composite reverse osmosis membranes(PA-RO-x, x represents DMAc concentration), N, N'-dimethylacetamide(DMAc) was applied as co-reagent added into the aqueous m-phenylenediamine solution for interfacial polymerization reaction with trimesoyl cloride. Characterization of the PA-RO-x membranes by X-ray photoelectron spectroscopy(XPS) and attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectroscopy confirmed that with the increase of DMAc concentration, the content of cross-linked amide linkages in PA-RO-x membranes increased relative to the li-ner pendant carboxylic acid groups. By the field emission scanning electron microscope(FE-SEM) and atomic force microscope(AFM), it is obviously showed that the surface morphology gradually changed and the surface roughness of composite reverse osmosis membranes increased as the increase of DMAc content. The static water contact angle measurement with sessile drop method revealed that the hydrophilicity of the composite reverse osmosis membranes was enhanced after DMAc was added. According to the above mentioned charac-terization results, it was confirmed that DMAc play a key role that could effectively reduce the immiscibility between aqueous phase and oil phase, and help to improve the diffusion rate of m-phenylenediamine from aqueous phase to n-hexane for accelerating the reaction between m-phenylenediamine and trimesoyl cloride. At the same time, the increase of the linkages of cross-linked amide can be as hydrogen-bond sites, which can be beneficial for water molecules penetrate through the polyamide composite reverse osmosis membranes quickly without considerable losing the salt rejection. The higher the surface roughness of the membranes, the higher the permeate flux. The water permeate flux and NaCl rejection of PA-RO-5.2(DMAc concentration is 5.2%, mass fraction) reached 66.1 L/m2•h and 98.7%, respectively, for 2 g/L NaCl under 1.6 MPa. Compared with the polyamide reverse osmosis composite membrane without DMAc addition, the permeate flux of PA-RO-5.2 increased by 115% and the desalination rate decreased by 0.9%. © 2021, Editorial Department of Chem. J. Chinese Universities. All right reserved. 
Co-reagent, N, N'-dimethylacetamide; Per-meate flux; Polyamide composite reverse osmosis membrane; Salt rejection