Abstract

Degradation of 2.5 mM EDTA-Fe solution was performed in a coupled photocatalytic-biological reactor. The system consists of a photochemical annular reactor filled with Tio 2 immobilized on glass Raschig rings coupled with an activated sludge continuous reactor. Around 50 % of EDTA degradation was reached after 150 min irradiation. Simultaneously a four-fold increase in biodegradability, measured as BOD 5/COD ratio, was observed. The activated sludge is not capable to degrade the complex EDTA-Fe but it removed partially the COd and efficiently the BOD 5 of the photochemically treated solution. © Selper Ltd., 2007.