Highly Efficient Removal of Chromium, Methylene Blue and Methyl Orange Using Electrospun Polyurethane as a Support in Heterogeneous Fenton Reaction

Electrospun membranes act as a support so that the iron (III) ions can be immobilized on polymer substrates to create heterogeneous Fenton catalysts with high activity, low iron leaching and improved stability without generating iron hydroxide sludge. In this study, functionalization of electrospun polyurethane (PU) is done using triethanolamine (TEA) and used as a novel support for heterogeneous Fenton catalyst. The fabricated membranes were characterized using scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) to analyze the effective doping of ferric chloride (FeCl₃) and amine compounds properly into the fibrous electrospun PU. The porous nature and increased wettability resulted in improved adsorption and further degradation. The composite microfibrous membrane showed highly efficient degradation of 98% for chromium, 93% for methyl orange (MO) and 89% for methylene blue (MB) using the Fenton reaction reported for the first time. Experimental conditions were optimized at a pH of 3 for chromium (Cr(III)) and MO, and at a pH of 11 for MB, with an initial concentration of 10 ppm, catalyst loading of 2 g/L and temperature of 50 ℃. From the detailed kinetics study, data fitted well the first order reaction kinetics, and the membranes were successfully reused for five cycles after regeneration.