Solid-state blending for the preparation of porous eco-friendly PCL membranes: Potential for filtration applications.

This article focuses on the development of biodegradable porous microfiltration (MF) membranes fabricated from poly (ε-caprolactone) (PCL) using a solventless cryomilling, hot pressing, and porogen leaching method. Eco-friendly porogens—poly (ethylene oxide) (PEO) and salt—were used to create porosity, while wood sawdust (WSD) and potassium aluminum sulfate (alum) were incorporated as fillers to modify hydrophilicity, mechanical strength, and antimicrobial properties. The resulting membranes exhibited dense surface skins with lamellar porous structures and mean pore sizes within the MF range (0.15–0.21 μm). Membranes containing WSD showed increased hydrophilicity but reduced mechanical properties, whereas alum addition enhanced hydrophilicity but caused embrittlement and accelerated degradation. Filtration tests using industrial textile wastewater demonstrated that membranes fabricated with both PEO and salt porogens achieved higher pure water flux and comparable or better turbidity reduction than commercial cellulose nitrate membranes, indicating the potential of this green fabrication approach for sustainable water treatment applications.