US scientists turn contaminated water into 92% pure fertilizer, fuel

Yale researchers have developed a novel electrochemical method to convert nitrate—a common and harmful water pollutant—into ammonia with a remarkable 92% efficiency. This breakthrough addresses two critical challenges in nitrate conversion: achieving high selectivity (minimizing unwanted byproducts) and high activity (speed of conversion). The team combined an ionophore, which binds and retains nitrite (a problematic intermediate), with an electrified membrane made of copper and carbon nanotubes. This combination allows nitrite to be fully converted into ammonia before it escapes, enabling rapid conversion in just six seconds—significantly faster than traditional methods that take hours. The system was tested successfully on real water samples from a lake and a wastewater treatment plant, demonstrating stability and practical applicability. This technology not only promises cleaner water by removing nitrate pollutants but also produces ammonia, a valuable resource for fertilizers and carbon-free fuels. The researchers believe their approach, detailed in Nature Chemical Engineering, could be scaled up for conventional water treatment, offering a