Degradation of crystal violet (CV) from aqueous solutions using ozone, peroxone, electroperoxone, and electrolysis processes: a comparison study

In this study, the degradation of crystal violet (CV) was investigated by different oxidation processes; ozone (OZ), peroxone (PO), electrolysis (E), electrolysis/H₂O₂ (ECP), electroperoxone (EPO), and electrolysis/peroxene/H₂O₂ (EPOP). Main parameters including contact time, pH, CV concentration, and effect of scavengers were studied. The results showed that all processes were capable of CV decolorization. Among these processes, peroxone and electrolysis/peroxene/H₂O₂ with efficiency about > 90% were more effective than other ones. A significant decrease in oxidation rate of CV was observed by adding scavengers. This fact was due to higher affinity to react with free radicals. To confirm degradation of CV, FTIR spectra and nitrate ion level were taken. Also, to recognize toxicity the treated wastewater was tested against coliform bacteria. Growths of Escherichia coli in EMB medium were observed. As a result, it confirms that the treated effluent can be discharged to environment.