Fabrication and characterization of electrospun PLA/tuff composite membranes as potential eco-friendly metal adsorbents

In this study, electrospinning was successfully employed to fabricate membranes based on polylactic acid (PLA), a polymer known for its biodegradability, containing varying amounts of opalized tuff (0, 2, 5, and 10 wt%). The addition of tuff introduced active mineral sites within the fibrous network, while the PLA matrix ensured mechanical stability, environmental sustainability, and prevention of secondary pollution. The electrospun membranes exhibited a uniform fibrous morphology with well-developed surface porosity, as confirmed by scanning electron microscopy. X-ray powder diffraction and Fourier-transform infrared spectroscopy verified the preservation of the characteristic structural features of both PLA and tuff, indicating successful incorporation of the filler without chemical alteration of the polymer matrix. Scanning electron microscopy combined with energy dispersive X-ray spectroscopy analysis demonstrated effective adsorption of nickel (Ni2+) and lead (Pb2+) ions from aqueous solutions, attributed to the high surface activity of the silicate mineral phase. These findings highlight the synergistic combination of a renewable, environmentally friendly polymer and a naturally occurring mineral filler to produce efficient and eco-friendly adsorptive membranes for heavy metal removal from aqueous solution.