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The removal of nitrobenzene (NB) in microbial electrochemical systems generally requires electrical power to operate systems in the mode of microbial electrolysis cells (MECs). The present study demonstrates that single‐chamber microbial fuel cells (S‐MFCs) assembled with a bioanode and an activated carbon (AC) air cathode could simultaneously remove NB and generate electricity. S‐MFCs with 1 mM NB exhibit long term NB tolerance and stable electricity production, with NB removal up to 98% in an operation cycle and a maximum power of 16.2 ± 1.3 W m−3. High NB loadings significantly inhibited the activity of anodic biofilms, but the inhibition was reversible. Investigating the removal of NB and its reduction product aniline (AN) in different operations supported the fact that the adsorption at the AC air cathode is the main pathway for the removal of NB and AN from solution, except for the partial conversion of NB to AN by anaerobic reduction in solution. In S‐MFCs, the activated carbon in the cathode plays both functions: catalyzing the oxygen reduction reaction and adsorbing NB and AN, so that the S‐MFC assembled with the AC air cathode, unlike most NB removing MECs, functions as a system with both NB removal and electricity production. [ABSTRACT FROM AUTHOR]

Great attention has been focused on Gram-negative bacteria in the application of microbial fuel cells. In this study, the Gram-positive bacterium Enterococcus faecalis was employed in microbial fuel cells. Bacterial biofilms formed by E. faecalis ZER6 were investigated with respect to electricity production through the riboflavin-shuttled extracellular electron transfer. Trace riboflavin was shown to be essential for transferring electrons derived from the oxidation of glucose outside the peptidoglycan layer in the cell wall of E. faecalis biofilms formed on the surface of electrodes, in the absence of other potential electron mediators (e.g., yeast extract). [ABSTRACT FROM AUTHOR]

beta-cyclodextrin can react with nitrobenzene to form an inclusion complex which is characterized by (1)H NMR and powder X-ray diffractometry. The ratio of beta-CD to NB in inclusion complex is determined as 1:1. At 25 degrees C, the dissociated constant, K(D), of the inclusion complex is measured as 6.5 x 10(-3) M in neutral solution (pH=7.0), but in alkali (pH=13.5), K(D) is 3.2 x 10(-2) M which is much larger than that measured in neutral.