Chitosan-titanium oxide fibers supported zero-valent nanoparticles: Highly efficient and easily retrievable catalyst for the removal of organic pollutants

Different chitosan-titanium oxide (CS-TiO(2)-x, with x = TiO(2) loadings of 1, 5, 10,15 and 20 wt%) nanocomposite fibers were prepared and kept separately in each salt solution of CuSO(4), CoNO(3), AgNO(3) and NiSO(4) to adsorb Cu(2+), Co(2+), Ag(+), and Ni(+) ions, respectively. The metal ions loaded onto CS-TiO(2) fibers were reduced to their respective zero-valent metal nanoparticles (ZV-MNPs) like Cu(0), Co(0), Ag(0) and Ni(0) by treating with NaBH(4). The CS-TiO(2) fibers templated with various ZV-MNPs were characterized and investigated for their catalytic efficiency. Among all prepared ZV-MNPs, Cu(0) nanoparticles templated on CS-TiO(2)-15 fibers exhibited high catalytic efficiency for the reduction of dyes (methyl orange (MO), congo red (CR), methylene blue (MB) and acridine orange (AO)) and nitrophenols (4-nitrohphenol (4-NP), 2-nitrophenol (2-NP), 3-nitrophenol (3-NP) and 2,6-dinitrophenol (2,6-DNP)). Besides the good catalytic activities of Cu/CS-TiO(2)-15 fibers, it could be easily recovered by simply pulling the fiber from the reaction medium.