4. Conclusions
The following general conclusions can be drawn from this
study:
• H2O2/Fe2+ is a critical parameter for improving the efficiency
of the Fenton’s process.Keeping theH2O2/Fe2+ ratio constant
within the specified range, it is possible to decrease FeSO4
and H2O2 concentrations remarkably, still achieving nearly
the same COD removal efficiency.
• Fenton’s coagulation removes organic compounds which
were not removed by Fenton’s oxidation, indicating that the
Fenton’s coagulation act as a polishing step.
Considering the relatively high FeSO4 and H2O2 concentrations
required, Fenton’s treatment may be rated as uneconomical
for the large volumes of dyeing wastewater. However, degradation
of the pollutant organics into biodegradable products by
relatively low Fenton’s reagent doses and applying biological
treatment following it, might be a more economical and effective
method to achieve discharge standards