Reduction of Fe(III)EDTA in a NOx scrubber liquor by a denitrifying bacterium and the effects of inorganic sulfur compounds on this process.
Biological reduction of Fe(III)EDTA is one of the key steps in nitrogen oxides removal in the integrated approach of metal chelate absorption combined with microbial reduction. Paracoccus denitrificans ZGL1 was used as a model bacterium to evaluate the process of Fe(III)EDTA reduction by such microorganisms that could carry out the simultaneous reduction of NO chelated by Fe(II)EDTA (Fe(II)EDTA-NO) and Fe(III)EDTA. Enzymes analysis indicated Fe(III)EDTA reductase of ZGL1 was located both in the membrane and cytoplasmic fractions. Glucose was identified as the most efficient electron donor for Fe(III)EDTA reduction. Better reduction performance was obtained with higher initial cell concentration corresponding to a specific reduction rate of 8.7 μmol h(-1) mg protein(-1). The presence of sulfate and thiosulfate had no influences on both cell growth and Fe(III)EDTA reduction. Fe(III)EDTA reduction rate and cell growth could be inhibited by addition of sulfite mainly due to its direct and indirect toxic effects.
Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, PR China.
Xiyang
X
Dong
Yu
Y
Zhang
Jiti
J
Zhou
Ning
N
Li
Mingxiang
M
Chen
D001673:Biodegradation, Environmental / Q000187:drug effects; D002244:Carbon / Q000494:pharmacology; D003116:Color; D058440:Denitrification / Q000187:drug effects; D004492:Edetic Acid / Q000378:metabolism; D038181:FMN Reductase / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism*; D007700:Kinetics; D009566:Nitrates / Q000378:metabolism*; D009573:Nitrites / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D010231:Paracoccus denitrificans / Q000166:cytology / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D013457:Sulfur Compounds / Q000494:pharmacology*; D013885:Thiosulfates / Q000378:metabolism; D013997:Time Factors; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology*
D002244:Carbon; D004492:Edetic Acid; D038181:FMN Reductase; D005290:Ferric Compounds; D009566:Nitrates; D009573:Nitrites; D013457:Sulfur Compounds; D013885:Thiosulfates; D062065:Wastewater; C023903:ferric citrate iron reductase; C019179:Fe(III)-EDTA