Microbial denitrification by immobilized bacteria Pseudomonas denitrificans stimulated by constant electric field

A comparative study of microbial reduction of nitrate ions by immobilized Pseudomonas denitrificans cells in the presence and in the absence of a constant electric field was carried out. The experiments were carried out in a continuous stirred tank reactor at a broad range of dilution rates. The cathode potential was maintained constant around the standard potential value of the nitrate/nitrite redox couple. The residual outlet concentrations of nitrate, when the electric field was applied, were much lower than those obtained without the electric field, all other conditions being equal. It was demonstrated that the electric field had a significant effect on the nitrate reduction rate allowing the use of much higher inlet flow rates compared to the flow rate in the absence of an electric field.