Treatment of wastewater derived from dinitrodiazophenol (DDNP) manufacturing by the Fe/Cu/O3 process

Abstract

In this paper, the Fe/Cu bimetallic particles and ozone were combined to decompose or transform the toxic and refractory pollutants in dinitrodiazophenol (DDNP) wastewater. Firstly, operational parameters including theoretical Cu mass loading (TML_Cu), Fe/Cu dosage, initial pH, O₃ flow rate and treatment time were optimized respectively. The maximum COD removal efficiency (85.3%) and color removal efficiency (95.0%) were obtained under the optimal conditions (i.e., theoretical Cu mass loading (TML_Cu) = 0.02 g Cu per g Fe, Fe/Cu dosage = 20 g L⁻¹, initial pH = 5.0, O₃ flow rate = 0.3 L min⁻¹, treatment time = 15 min). Then, in order to confirm the superiority of the Fe/Cu/O₃ process, three control experiment systems including Fe/Cu, O₃ and Fe⁰/O₃ processes were set up under the same conditions. In addition, the UV-vis and FTIR results confirm the main pollutants in DDNP wastewater were oxidized and generated intermediates, which revealed the superiority of Fe/Cu/O₃ process. Thus, the DDNP wastewater could be treated by Fe/Cu/O₃ process in a promising way.