From IIT Guwahati, a device to turn wastewater into energy

The device uses microbes to convert chemical energy in organic substrates into electrical energy

Researchers at the Indian Institute of Technology Guwahati have developed a microbial fuel cell (MFC), a bio-electrochemical device that can generate “green energy” by treating wastewater.

The researchers said the device offered a dual benefit — generation of bioelectricity and waste management — by converting chemical energy contained in organic substrates into electrical energy through microbes.

The Department of Science and Technology supported the research led by Mihir Kumar Purkait and his Ph.D student Mukesh Sharma of IIT Guwahati’s Department of Chemical Engineering.

The IIT Guwahati claimed the device could be used for obtaining clean energy from municipal wastewater economically.

“MFC is a bio-electrochemical reactor system that utilises electrons liberated in the biochemical oxidation of organic substrates catalysed by anaerobic microbes. A conventional MFC reactor comprises an anaerobic biotic anode chamber, an aerobic biotic or abiotic cathode chamber, and a separator such as a proton exchange membrane (PEM),” Mr. Purkait explained.

The active biocatalyst in the anodic chamber anaerobically oxidises organic matter present in wastewater to produce electrons and protons. Protons are transported to the cathodic chamber through the PEM. The external circuit conducts the electrons to the cathode, completing the electrical circuit.

At the cathode, electrons and protons reacted in the presence of oxygen (or another electron acceptor), which got reduced to water, the researchers said.