BACKGROUND: In the BioDeNOX technology for NOX removal from flue gas, bioreduction of Fe(II)EDTA-NO and Fe(III)EDTA are core processes. In this study, a newly isolated strain, Paracoccus denitrificans, was used to reduce Fe(II)EDTA-NO with glucose and Fe(II)EDTA as donor electrons. To better understand the change law of Fe(II)EDTA, the process of Fe(II)EDTA-NO reduction by P. denitrificans with glucose and Fe(II)EDTA as electron donors was investigated, and the factors that might affect Fe(II)EDTA concentration were studied. RESULTS: For the bioreduction process of Fe(II)EDTA-NO, P. denitrificans could use glucose and Fe(II)EDTA as electron donors. At different stages, primary electron donors were different, thereby affecting the concentration of Fe(II)EDTA in the system. It was also proved that this strain not only reduced Fe(III)EDTA with glucose as the electron donor but also secreted several substances that reacted with Fe(III)EDTA, resulting in increased Fe(II)EDTA concentration in the solution. CONCLUSIONS: This work has shown that P. denitrificans can reduce Fe(II)EDTA-NO and Fe(III)EDTA simultaneously to regenerate NOX absorption solution. (c) 2012 Society of Chemical Industry