Integration of Fenton with biological and physical–chemical methods in the treatment of complex effluents: a review

ABSTRACT

The management of complex effluents is a great environmental challenge because they contain toxicants or recalcitrants which make conventional treatment methods inadequate. The use of Fenton oxidation in the treatment of these effluents has an edge over other advanced oxidation processes methods due to its simplicity in application. However, detailed studies on its use in common complex effluents are not documented. The aim of this study was to review the use of Fenton in the treatment of refractory compounds and toxicants in complex effluents. The most applied Fenton processes in complex effluent treatment include; photo-Fenton, classic Fenton, heterogeneous Fenton, electrochemical Fenton, ultraviolet and vacuum Fenton processes. A detailed review on how the Fenton processes have been integrated with other processes, including biological and physical/chemical processes, was done. The effluent qualities determine the integration processes and the stage of Fenton application. A criterion for determining the application stage of Fenton oxidation in the integrated treatment of complex effluents was proposed. The use of Fenton processes in the pretreatment or post-treatment of complex effluents was also studied. Detailed comparative studies on how the integration of Fenton processes affects the process efficiency and overall process costs are lacking and should be studied further.

KEYWORDS:

• Wastewater
• complex
• treatment
• recalcitrants
• Fenton

Additional information

Funding

The financial support by Deutscher Akademischer Austausch Dienst and National Commission of Science, Technology and Innovation Kenya, reference no. 91548162, is also acknowledged.