Preparation of polysulfone-based nanofiber Janus membrane for membrane distillation containing organic pollutants

• Published in: npj clean water 2024-06, Vol.7 (1), p.51-15, Article 51
• Main Authors: Wu, Zhuobin, Zheng, Ke, Zhang, Guichang, Huang, Longwei, Zhou, Shaoqi
• Format: Article
• Language: English
• Subjects: 639/301/1005; 639/925/357; Antifouling; Antifouling substances; Aquatic Pollution; Desalination; Distillation; Earth and Environmental Science; Energy sources; Environment; Fouling; Harnesses; Humic acids; Hydrophobicity; Membranes; Molecular dynamics; Nanotechnology; Polysulfone; Polysulfone resins; Polyvinylpyrrolidone; Rejection rate; Saline water; Salt rejection; Tetraethoxysilane; Tetraethyl orthosilicate; Waste Water Technology; Wastewater treatment; Water Industry/Water Technologies; Water Management; Water Pollution Control; Water Quality/Water Pollution; Water treatment; Wettability; Wetting
• ISSN: 2059-7037; 2059-7037
• DOI: 10.1038/s41545-024-00342-5

Membrane distillation is an emerging wastewater treatment technology that harnesses low-grade heat as an energy source and exhibits potential for complete desalination. Nonetheless, two notable challenges hinder the practical application of this technology: membrane wetting and fouling. To counter these challenges, an innovative anti-fouling Janus membrane with asymmetric wettability was developed through electrospinning. The hydrophobic layer was formed using tetraethyl orthosilicate/polysulfone (PSF), and the superhydrophilic layer was created using polyvinylpyrrolidone (PVP)/PSF. A sensitive adhesion probe was used to assess the anti-fouling performance of the Janus membrane against oil. Molecular dynamics simulation suggested that PVP reduced the adsorption tendency of the membrane for humic acid (HA). Under experimental conditions involving saline water with HA and a saline oil–water emulsion, the non-Janus membrane suffered severe fouling, resulting in rapid water permeate flux decline. However, the Janus membrane demonstrated consistent permeate flux (26.84 LMH and 24.92 LMH) and an impressive salt rejection rate (> 99.99%). This study suggests that the Janus membrane, with its high permeate fluxes and remarkable resistance to fouling and wetting, could be an effective solution for wastewater treatment, with considerable potential for future application.