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

Abstract

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 10–20nm, 20–40nm, and 40–60nm 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 10–20nm exhibited the highest catalytic activity of the three CNTs under MW irradiation. Further, complete degradation was obtained using 10–20nm CNTs within 7.0min irradiation when 25mL MO solution (25mg/L), 1.2g/L catalyst dose, 450W, 2450MHz, and pH=6.0 were applied. The rate constants (k) for the degradation of SDBS, MB, MP, MO and BPA using 10–20nm CNTs/MW system were 0.726, 0.679, 0.463, 0.334 and 0.168min−1, respectively. Therefore, this technology may have potential application for the treatment of targeted organic pollutants in wastewaters.