Oxidative Degradation of Quinoline Using Nanoscale Zero-Valent Iron Supported by Granular Activated Carbon

The nano zero-valent iron supported granular activated carbon (nFe(0)/GAC or 2.5%-nFe(0)/GAC) was synthesized by the liquid chemical reduction method and further used for the oxidative degradation of quinoline. The 2.5%-nFe(0)/GAC was characterized by various techniques such as Brunauer-Emmett-Teller (BET) surface area, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). It was ascertained that iron is of zero state and well dispersed on GAC. The 2.5%-nFe(0)/GAC exhibited an H4 type hysteresis loop with a surface area of similar to 240 m(2)/g. The kinetic study reveals that quinoline degradation follows the pseudo-first order. At optimum conditions of pH = 4, m = 7.5 g/L, C-o = 100 mg/L, and T = 303 K, it was observed that (1) similar to 93% of quinoline and similar to 63% of total organic carbon (TOC) removal is obtained, (2) iron leaching is within the permissible limit, and (3) it requires similar to 63 +/- 5 min for completion of the half-life of quinoline. The activation energy is similar to 22.4 kJ/mole, which indicates that quinoline removal is controlled by a chemical surface reaction. The degradation by-products of quinoline were analyzed. The mass fragments (of m/z = 146 and 178) due to hydroxylation were obtained, which were further reduced into low m/z fragments, which may lead to mineralization of quinoline. (C) 2015 American Society of Civil Engineers.