Enhancing the Cu (II) Removal in Water Using Functional Hybrid Membranes

Abstract

This work developed hybrid EIPS/NIPS membranes of poly (butylene adipate-co-terephthalate) (PBAT) with nanocurcumin (NC) and/or Cloisite 20A (C20A). The dispersed phases were characterized by dynamic light scattering (DLS), ζ potential, X-ray diffractometry (XRD), scanning electron microscopy (SEM), and fourier-transform infrared spectroscopy (FTIR), while XRD, SEM, FTIR, mechanical properties, contact angle, and copper sorption evaluated the composite membranes. DLS analysis indicated that the dispersed phases present a nanometric size distribution; ζ potential measurements showed low electrostatic stability, explaining the agglomeration effects observed. Pure PBAT membranes presented macro-pores throughout their structure, which showed a slight size reduction with the inclusion of NC and C20A. The membrane’s mechanical performance was affected by the presence of the pores that functioned as stress-concentrating defects, and the inclusion of the dispersed phases increased the elastic modulus and tensile strength, especially for PBAT/0.5% C20A with values 18.7 and 8.9% higher than those of pure PBAT, respectively. Hybrid EIPS/NIPS membranes showed a hydrophilic nature with all the contact angle measurements lower than 90°. The sorption tests using a high-concentration copper solution (1,000 mg/L) showed a removal of around 25%. These results highlighted the development of new eco-friendly membranes using NC and C20A as dispersed phases with the potential to remove toxic elements from water.