Degradation Reactive Black 5 dye from aqueous solutions using ozonation with pumices and pumices modified by nanoscale zero valent iron (nZVI)

Reactive Black 5 (RB5) dyes are a dye widely used in textile industries. The nanocatalytic ozonation of RB5 solution in the presence of pumice modified with nanoscale zero valent iron (nZVI) catalysts and pumice raw investigated in a laboratory scale batch reactor. The effects of solution pH (3-11), reaction time, pumice dosage (10, 15 and 20 g/L) and COD removal were evaluated. Natural mineral raw pumice and pumice-nZVI was used directly in nanocatalytic ozonation of dye of RB5 solution. Compared with raw pumice, pumice-nZVI into the ozonation reactor greatly accelerated the rate of RB5 degradation. The results indicate that with increasing (pH, and pumice dosage) increased rate RB5 degradation. Molecular ozone direct oxidation mechanism was proved in nanocatalytic ozonation with pumice, and hydroxyl radical mechanism was demonstrated to play a main role in nanocatalytic ozonation with nZVI.