Flexible biological arsenite oxidation utilizing NOxand O2as alternative electron acceptors.
The feasibility of flexible microbial arsenite (AsIII) oxidation coupled with the reduction of different electron acceptors was investigated. The results indicated the acclimated microorganisms could oxidize AsIIIwith oxygen, nitrate and nitrite as the alternative electron acceptors. A series of batch tests were conducted to measure the kinetic parameters of AsIIIoxidation and to evaluate the effects of environmental conditions including pH and temperature on the activity of biological AsIIIoxidation dependent on different electron acceptors. Kinetic results showed that oxygen-dependent AsIIIoxidation had the highest oxidation rate (0.59 mg As g-1VSS min-1), followed by nitrate- (0.40 mg As g-1VSS min-1) and nitrite-dependent AsIIIoxidation (0.32 mg As g-1VSS min-1). The kinetic data of aerobic AsIIIoxidation were fitted well with the Monod kinetic model, while the Haldane substrate inhibition model was better applicable to describe the inhibition of anoxic AsIIIoxidation. Both aerobic and anoxic AsIIIoxidation performed the optimal activity at the near neutral pH. Besides, the optimal temperature for oxygen-, nitrate- and nitrite-dependent AsIIIoxidation was 30 ± 1 °C, 40 ± 1 °C and 20 ± 1 °C, respectively.
School of Chemical Engineering and Energy, Zhengzhou University, 100 Science Avenue, 450001, PR China.
Jie
J
Wang
School of Chemical Engineering and Energy, Zhengzhou University, 100 Science Avenue, 450001, PR China. Electronic address: wanjunfeng@zzu.edu.cn.
Junfeng
J
Wan
School of Chemical Engineering and Energy, Zhengzhou University, 100 Science Avenue, 450001, PR China.
Zihao
Z
Wu
School of Chemical Engineering and Energy, Zhengzhou University, 100 Science Avenue, 450001, PR China.
Hongli
H
Li
School of Chemical Engineering and Energy, Zhengzhou University, 100 Science Avenue, 450001, PR China.
Haisong
H
Li
GRESE EA 4330, Université de Limoges, 123 Avenue Albert Thomas, F-87060, Limoges Cedex, France; INSERM, U1092, Limoges, France.
Christophe
C
Dagot
School of Chemical Engineering and Energy, Zhengzhou University, 100 Science Avenue, 450001, PR China.
Yan
Y
Wang
D018053:Arsenites / Q000737:chemistry*; D004583:Electrons; D007700:Kinetics; D009566:Nitrates / Q000737:chemistry*; D009573:Nitrites / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*
D018053:Arsenites; D009566:Nitrates; D009573:Nitrites; C015001:arsenite; D010100:Oxygen
Acclimatized sludge; Biological arsenite oxidation; Dynamic modeling; Electron acceptor