Green-synthesized AgNP/bc-anchored cellulose acetate composites derived from waste textiles: physicochemical, biological, and filtration performance for advanced applications

Cellulose acetate has gained remarkable interest due to its biocompatibility, easy formability, and moderate physical properties. In this study, silver particles synthesized by two different green methods were anchored with biocarbon (AgP-bc) in cellulose acetate (CA), which was synthesized from textile waste using a chemical route. The effects of AgP preparation methods reduced with quince extract in solution (Method I) and powder form (Method II) were monitored and compared mainly by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses. Water uptake, porosity, and water contact angle measurements were carried out, and the surface areas of the composites were determined by multi-point BET analysis. Antimicrobial studies were conducted to evaluate the biological activity of the composites. Cellulose acetate was successfully prepared from textile waste, and the methods used in AgP preparation significantly influenced both the physical and antimicrobial properties of the composites. AgP-bc-CA1 exhibited a high BET surface area and measurable, supportive antimicrobial activity against Escherichia coli O157:H7 and Staphylococcus aureus. The flat-sheet composite membranes achieved a flux of 51.3 L·m⁻²·h⁻¹·bar⁻¹ and a methyl orange (MO) rejection efficiency of 54.2% during filtration. Smooth-surfaced AgP-bc-CA1 demonstrated the best fouling resistance. The composites, produced as flat-sheet membranes with homogeneous AgP distribution enabled by the biocarbon additive, are suitable for filtration applications, with antimicrobial activity serving as a supportive functional property. Cellulose acetate was produced from waste textiles, enabling an environmentally sustainable composite system. AgP–biocarbon was incorporated into the cellulose acetate matrix via solution precipitation (Method I) and powder addition (Method II), demonstrating the strong influence of preparation method on pore structure and surface morphology. Method I provided more homogeneous additive distribution and controlled internal pore architecture, resulting in improved filtration performance with methyl orange rejection efficiencies up to ~ 54% and enhanced fouling resistance. Although antimicrobial activity was not the primary design objective, AgP-containing composites exhibited supportive antibacterial effects against E. coli O157:H7 and S. aureus (inhibition zones up to ~ 11 mm), supporting potential use in food-contact, filtration, and selected medical or biomedical applications.