Figure 1.
Overview of a reverse microbial fuel cell which uses the ammonia/nitrite redox couple as a mediator and ammonia-oxidizing Nitrosomonas europaea cells as biocatalysts.
Figure 2.
Linear sweeps of nickel, copper and glassy carbon rotating disk electrodes in 50 mM Phosphate Buffer +50 mM Sodium Nitrite at pH 7.0 at 400
rpm. Inset : constant current (2 mA/cm2) experiments in 50 mM Phosphate Buffer +50 mM Sodium Nitrite at pH 7.0 with nickel, copper and glassy carbon rotating disk electrodes at 400 rpm.
Figure 3.
Current efficiency of nitrite reduction to ammonia as a function of percentage of nitrite converted to ammonia in spent media from the bioreactor.
Inset shows the current efficiencies for 20 mM sodium nitrite in 100 mM phosphate buffer as a function of applied potential in batch experiments in an undivided three electrode cell with a glassy carbon cathode.
Table 1.
Summary of biokinetic and stoichiometric parameters describing growth of wild-type Nitrosomonas europaea on electrochemically regenerated media.
Figure 4.
Ammonia removal efficiency and observed biomass yield for continuous flow cultivated Nitrosomonas europaea.
Period 1 was defined by growth on synthetic media prepared from ACS grade chemicals. Period 2 was defined by cultivation on spent media from Period 1 that was electrochemically regenerated. Period 3 was defined by cultivation on spent media from Period 2 that was electrochemically regenerated. COD represents the chemical oxygen demand associated with complete oxidation to CO2. Replicate results are presented in Figure S1.