Photocatalytic removal organic matter and bacteria simultaneously from real WWTP effluent with power generation concomitantly: Using an Er Al ZnO photo-anode

Abstract

Abstract Wastewater treatment plant (WWTP) effluent is one of the most bulk water body that carries organic matters which is promising for energy catching, but it also contains complex un-degradable organic matters with low concentrations. Integration of advanced treatment of Wastewater treatment plant (WWTP) effluent and electricity generation is an attractive method but rarely reported. We innovatively applied a photocatalytic fuel cell (PFC) with a highly efficient Er-Al co-doped ZnO photo-anode to treat the WWTP effluent, which realized simultaneous advanced organic matters removal, bacteria disinfection, and considerable electricity generation. In the constructed visible light-driven PFC system, the chemical oxygen demand (COD) and dissolved organic carbon (DOC) removal efficiencies achieved 69.7% and 53.0%, respectively. The soluble microbial products decreased significantly. Both of the total bacteria cell and Escherichia coli (E. coli) cell accounts showed a ∼99% disinfection efficiency. Advanced electricity generation capability was simultaneously observed, in which the open-circuit voltage, short-current density, and maximum power density were 0.55 V, 9.13 µA cm−2 and 1.83 µW cm−2, respectively, with the fill factor as high as 0.36. In summary, the proposed PFC open up more opportunities for WWTP effluent reusing and clean energy generation.