摘要
Membrane distillation (MD) encounters severe operational bottlenecks arising from complex organic fouling coupled with oxidative membrane degradation during inevitable chemical cleaning. Conventional polyamide (PA) membranes are intrinsically susceptible to chlorine attack, which further exacerbates this issue. To overcome this critical bottleneck, a novel dual layer thin-film composite (TFC) Janus membrane (denoted as TFC (PE-PA) ) was developed via sequential interfacial polymerization (SIP) strategy. An ultrathin polyester (PE) skin layer was grown in situ directly onto a highly permeable PA substrate. The as-prepared composite membrane features a significantly smoothed surface topography and a highly hydrophilic character, which together establish a robust hydration barrier. This unique architecture effectively repels complex foulants, including oil droplets and amphiphilic organics. Consequently, the membrane exhibited exceptional durability and maintained near-complete salt rejection throughout 120 h of continuous desalination of hypersaline wastewater with a highly complex matrix. Furthermore, the ester-rich PE top layer lacks the vulnerable amide nitrogen sites that typically trigger chlorine-induced depolymerization. This inherent structural advantage enables the top layer to function as a robust chemical shield. The membrane demonstrated outstanding chemical inertness under a massive cumulative chlorine exposure of 72,000 ppm h at the highly aggressive pH of 5. During a rigorous 160-h long-term test comprising 32 consecutive cycles of organic fouling and aggressive chlorination cleaning, the dual-layer membrane retained an unprecedented flux recovery rate (FRR) exceeding 96.16%. This rational interfacial design successfully decouples intrinsic material vulnerability from long-term separation performance, offering a highly reliable engineering solution for sustainable industrial wastewater treatment.
危险品化学品经营许可证（带存储）