Inhibitory effect of inorganic ions on nitrobenzene oxidation by fluidized-bed Fenton process

This study investigated the effects of inorganic ions including chloride ions, dihydrogen phosphate ions and nitrate ions on the oxidation of nitrobenzene by the fluidized-bed Fenton process. The nitrobenzene degradation decreased with increasing chloride, dihydrogen phosphate and nitrate concentrations. Dihydrogen phosphate and chloride ions significantly inhibited nitrobenzene degradation. However, the inhibition caused by chloride ions could be overcome by extending the reaction time if the concentration of chloride ions was low. Nitrate did not have significant effect on nitrobenzene removal. The inhibition effect of each inorganic ion on the nitrobenzene degradation was in the order: H2PO4− ≫ Cl− > NO3−. In addition, the results also show that the removal efficiency of nitrobenzene by fluidized-bed Fenton process was higher than traditional Fenton process.

Graphical abstractThis study investigated the effects of inorganic ions on nitrobenzene oxidation by fluidized-bed Fenton process. Inhibition effect of each inorganic ion was in the order: H2PO4− ≫ Cl− > NO3−.Figure optionsDownload full-size imageDownload high-quality image (68 K)Download as PowerPoint slideResearch highlights▶ The degradation of nitrobenzene by fluidized-bed Fenton process is extremely sensitive to inorganic anions. ▶ The complexation reactions with ferric ions are the main reason for the inhibition of the degradation efficiency. ▶ In the presence of chloride and dihydrogen phosphate ions, nitrobenzene oxidation is strongly inhibited.