Chitosan coated polyacrylonitrile nanofibrous mat for dye adsorption.

Chitosan is a promising natural-derived polymer for dye adsorption owing to its rich source, good biodegradablity and high adsorption capacity. However, electrospinning of pure chitosan nanofiber needs high concentration of acid solution and the electrospinning productivity is very low due to its high degree of hydrogen bonding and polycationic nature. To solve the problem, the chitosan coated polyacrylonitrile nanofibrous mat (CPNM) was successfully prepared via a two-step fabrication process of polyacrylonitrile electrospinning and a subsequent chitosan coating. The chitosan was homogeneously adhered onto the PAN nanofibers, which improved the hydrophilicity and adsorption capacity of Acid Blue-113 significantly. The adsorption of Acid Blue-113 on CPNM fitted the pseudo-second-order kinetics model well, and the maximum adsorption capacity of CPNM calculated from the Langmuir isotherm model was 1708 mg/g with the average fiber diameter of 189 nm. The CPNM demonstrate the virtue of simple fabrication process, high adsorption capacity and good reusability, which is a promising adsorbent for dye removal.