Development of chitosan-TiO2 thin film and its application for methylene blue dye degradation

Abstract

ABSTRACT Fish processing industries are one of the pollution-causing sectors all over the world due to the generation of huge quantities of solid and liquid wastes and lacks proper treatment facilities. Wastewater treatment using nano-thin films will be one of the most promising technologies for the treatment of industrial effluents by saving considerable amount of money. Therefore, the current research aims to develop an energy-efficient, eco-friendly, cost-effective and green isolation technique for the production of natural polymer from crab shell followed by the development of nano thin films by dip-coating technique for the degradation of methylene blue dye. The stability studies of the nano thin films were performed at different environmental conditions. The characterisation techniques employed are Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and UV–Visible spectroscopy. A series of batch experimental studies were performed using the fabricated thin films for the degradation of methylene blue dye by varying the effluent solution pH (2.0 to 10.0), concentration of dye solution (0.1 mg/L – 1.0 mg/L), exposure time (30 min to 210 min) and number of layers (2 to 14) of thin-film deposition for the optimisation of processing conditions. The best processing conditions obtained from the batch study are pH 6.0, 0.60 mg/L dye concentration, 120 minutes of contact time and 12 layers of thin-film deposition. The experimental study demonstrates that the chitosan-TiO2 nano thin films were found to be effective in the treatment of industrial effluent containing methylene blue dye.