Evaluation of simultaneous reduction of Fe(II)EDTA‐NO and Fe(III)EDTA by a bacterial pure culture

Abstract

AbstractBACKGROUNDThe integrated approach of using metal chelate (e.g. Fe(II)EDTA) absorption combined with microbial reduction for nitric oxide (NO) removal has been a frequent topic of much recent study. The present study was undertaken to evaluate simultaneous Fe(II)EDTA‐NO and Fe(III)EDTA with Paracoccus denitrificans as a model microorganism.RESULTSThe experimental results suggested that Fe(III)EDTA reduction was severely inhibited by Fe(II)EDTA‐NO while the addition of Fe(III)EDTA could have a positive effect on the reduction of Fe(II)EDTA‐NO. Riboflavin, AQDS and vitamin B12 at 0.1 mmol L−1 did not have significant effects on simultaneous reduction of Fe(II)EDTA‐NO and Fe(III)EDTA. Addition of sulfide not only could directly react with Fe(II)EDTA‐NO and Fe(III)EDTA but also might play multiple roles in biological Fe(II)EDTA‐NO reduction and Fe(III)EDTA reduction. The respiratory inhibitor CuCl2 inhibited Fe(II)EDTA‐NO reduction as well as Fe(III)EDTA reduction while NaN3 and rotenone showed no measurable effects.CONCLUSIONSThe present study showed that Fe(II)EDTA‐NO reduction and Fe(III)EDTA reduction reacted upon each other. The roles of sulfide were divided in terms of biological and chemical interactions during the simultaneous reduction. CuCl2 could inhibit the simultaneous reduction rates. © 2013 Society of Chemical Industry