NEWS
Process design for bioelectrochemical recovery of NH4+ from wastewaters
How can we turn wastewater into something valuable? In this research, we’re developing a microbial electrolysis cell (MEC) that helps recover ammonium (NH4+) from wastewater by using electroactive microorganisms together with an externally applied electrical potential.
DC7
Doctoral Candidate: Amin Narimani Supervisors: Albert Guisasola, Zainab Ul Kausar, Marika Kokko
What we’re building
We’re working with a three-chamber MEC designed to separate treatment and recovery steps. It combines:
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Electroactive microorganisms at the anode that oxidize organic matter in wastewater,
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Electrodes that enable electron transfer through the circuit,
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A cation exchange membrane (CEM) to transport ammonium (NH₄⁺),
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And a hydrophobic gas-diffusion interface to extract NH₃ into a recovery chamber.
How it works
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At the anode, microorganisms oxidize organic matter and release electrons.
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We apply a controlled potential across the cell to drive the electrochemical process.
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This supports NH₄⁺ transport through the CEM toward the cathode.
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Near the cathode, alkaline conditions convert NH₄⁺ into NH₃.
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NH₃ passes through the gas-diffusion interface into the recovery chamber, where it can be captured as an ammonium salt.
Where we are right now
So far, batch tests with synthetic wastewater have shown stable operation and effective ammonia recovery.We are now operating the system in continuous mode to evaluate long-term stability and performance. Next, we will test the MEC with real digestate to assess how it behaves under realistic conditions.
