Microwave-induced carbon nanotubes catalytic degradation of organic pollutants in aqueous solution

In this study, a new catalytic degradation technology using microwave induced carbon nanotubes (MW/CNTs) was proposed and applied in the treatment of organic pollutants in aqueous solution. The catalytic activity of three CNTs of 10-20 nm, 20-40 nm, and 40-60 nm diameters were compared. The results showed that organic pollutants such as methyl orange (MO), methyl parathion (MP), sodium dodecyl benzene sulfonate (SDBS), bisphenol A (BPA), and methylene blue (MB) in aqueous solution could be degraded effectively and rapidly in MW/CNTs system. CNTs with diameter of 10-20 nm exhibited the highest catalytic activity of the three CNTs under MW irradiation. Further, complete degradation was obtained using 10-20 nm CNTs within 7.0 min irradiation when 25 mL MO solution (25 mg/L), 1.2 g/L catalyst dose, 450W, 2450 MHz, and pH = 6.0 were applied. The rate constants (k) for the degradation of SDBS, MB, MP, MO and BPA using 10-20 nm CNTs/MW system were 0.726, 0.679, 0.463, 0.334 and 0.168 min(-1), respectively. Therefore, this technology may have potential application for the treatment of targeted organic pollutants in wastewaters. (C) 2016 Elsevier B.V. All rights reserved.