Effect of Different Current Density on the Performance of Microbial Fuel Cell and Denitrification Activity

Abstract

Nitrate pollution of groundwater constitutes an important and rapid increasing environmental problem 1. One of the most common causes of nitrate pollution is the excessive use of fertilizers in intensive agriculture and irrigation with ammoniarich effluents discharged by wastewater treatment plants 2. Conventional physico-chemical methods used to remove nitrate from water contain ion exchange, reverse osmosis and electrochemical reduction and bioremediation 3. Among the techniques available for the removal of nitrate from groundwater, microbial denitrification stands out because of its economical environmental protection and being easy to a large-scale application 4. Denitrification is carried out by facultative aerobic bacteria which acts as a terminal electron acceptor in respiration under the conditional absence of oxygen 5,6. Microbial fuel cells (MFCs) represent an innovative remediation technology for waste and wastewater treatment, because they have the potential for simultaneous electricity generation and removal of organic pollutants. The cathodic compartments of microbial fuel cells are less studied and in most microbial fuel cells the cathodic reaction is abiotic, typically the reduction of oxygen or ferricyanide 7. In this study,