Researchers at MIT have developed a method to selectively remove micropollutants from water.
Published in the journal Energy and Environmental Science, the research details how an electrochemical process can select and remove organic contaminants, such as pesticides, chemical waste, and pharmaceuticals.
Ion-selective electrochemical systems, which permit the capture of targeted substances, can encounter trouble in acidic environments or environments that have a complex interplay of elements across the filtration surface. The MIT findings, led by Xiao Su, Ralph Landau Professor of Chemical Engineering T. Alan Hatton, focused on an asymmetric Faradaic cell that can act as both a cathode and anode can enhance ion separation, especially when targeting organic micropollutants. Indeed, the research found a 96 per cent effectiveness in selective capture of micropollutants.
The research team found that their process could remove molecules with as low concentration as in the parts-per-million. This offers potential for water treatment systems that use membrane filtration and electrodialysis and capacitive deionization, as the new method is not limited by their failings: temperature variance and high voltages, respectively.
“The system could be used for environmental remediation, for toxic organic chemical removal, or in a chemical plant to recover value-added products, as they would all rely on the same principle to pull out the minority ion from a complex multi-ion system,” Su said to Science Daily.
The researchers have previously won the 2016 MIT Water Innovation Prize, as Redox Water Solutions. At the time of their win, Xu said to the Massachusetts Clean Energy Center, “We expect our redox-water technology to offer a sustainable, energy-efficient method for wastewater treatment and environmental remediation, especially targeting dilute contaminants of high toxicity. Our aim is to use the opportunity offered by the [Water Innovation Prize] and support of MassCEC to take our technology forward in scaling up, and commercialization in the near future.”