Janus C-PAN/PH membrane for simulated shale gas wastewater (SGW) treatment in membrane distillation: Integrating surface property and catalytic degradation for anti-fouling

Membrane distillation (MD) is an effective method for treating shale gas wastewater (SGW), but membrane fouling remains a significant obstacle. To mitigate membrane fouling, we developed a dual-layer nanofibrous catalytic membrane (C-PAN/PH) that includes a hydrophilic polyacrylonitrile (PAN) layer with Co-TPML nano-catalysts and a hydrophobic poly(vinylidene fluoride-hexafluoropropylene) (PH) layer. This novel membrane can effectively treat feed solutions containing kerosene or aniline due to its surface hydration and peroxymonosulfate (PMS) activation. The water flux of the C-PAN/PH membrane was 38% higher than that of the PH membrane due to the higher thermal conductivity of hydrophilic layer. The C-PAN/PH membrane also exhibited stable flux for 10 h in treating 3,000 mg/L oil/water emulsion due to its hydration capability. Moreover, the C-PAN/PH membrane removed over 92% of the aniline within 2 min, and electron paramagnetic resonance (EPR) analysis indicated that reactive species (•OH and SO4•-) played a primary role in the degradation process. Density functional theory (DFT) simulations suggested that PMS was strongly adsorbed on Co with an adsorption energy of −3.77 eV. This study aimed to design a novel membrane specifically for MD in SGW treatment.