Removal of textile dyes from water by TiO2 nanoparticles immobilized on poly(ε-caprolactone) beads and foams

This study discusses the possibility of colloidal TiO 2 nanoparticles (NPs) immobilization onto poly(e-caprolactone) (PCL) beads and foams which can be utilized for removal of textile dyes from water by photodegradation. PCL foams were fabricated by environmentally friendly treatment of PCL beads in supercritical carbon-dioxide. PCL beads and foams loaded with colloidal TiO 2 NPs were used as photocatalysts for the removal of textile dyes C.I. Acid Orange 7 and C.I. Basic Yellow 28 from aqueous solutions (10 mg/L) under the illumination which simulated the sunlight. Unlike the PCL beads, the PCL foams provided complete discoloration of dye solution within 24 h of illumination. The PCL foams also exhibited excellent floatability that was maintained more than four weeks. Additionally, their photocatalytic activity was preserved within three repeated photodegradation cycles indicating that floating photocatalyst provided superior photocatalytic activity compared to non-floating PCL beads.