Degradation of 2,4-Dinitrophenol in Aqueous Solution by Microscale Fe~0/H_2O_2/O_3 Process

摘要

In this study, a microscale Fe~(0) (mFe~(0))/H_(2)O_(2)/O_(3) process was set up to degrade 2,4-dinitrophenol (DNP) in aqueous solution. First, key operating parameters including initial solution pH, mFe~(0) dosage, O_(3) flow rate, and H_(2)O_(2) dosage on Chemical Oxygen Demand (COD) removal efficiency were optimized through single-factor experiments. Under optimal conditions, COD removal efficiency reached 80.2%, and Biochemical Oxygen Demand (BOD_(5))/COD (B/C) ratio was elevated from 0 to 0.61 after 15 min treatment. Moreover, compared with control experiments (i.e., mFe~(0), O_(3), H_(2)O_(2), mFe~(0)/O_(3), mFe~(0)/H_(2)O_(2), O_(3)/H_(2)O_(2), mFe~(0)/H_(2)O_(2)/O_(2)), the mFe~(0)/H_(2)O_(2)/O_(3) process exerted better performance for degradation of DNP in aqueous solution due to the strong synergistic effect between mFe~(0), H_(2)O_(2), and O_(3). In addition, degradation and transformation of DNP were also analyzed. Finally, a reaction mechanism of mFe~(0)/H_(2)O_(2)/O_(3) process was proposed. It can be concluded that efficient mFe~(0)/H_(2)O_(2)/O_(3) process mainly resulted from the combination effects of heterogeneous and homogeneous catalytic ozonation process, Fenton and Fenton-like oxidation process, and direct oxidation process by O_(3). Therefore, the mFe~(0)/H_(2)O_(2)/O_(3) process could be proposed as a high-efficient treatment technology for removal of toxic refractory DNP from wastewater.