Imagine a world where industrial waste isn’t just reduced, it’s turned into something useful.
Imagine a world where industrial waste isn’t just reduced, it’s turned into something useful. This kind of circular economy is already in the works for carbon. Now, researchers in energy, environmental & chemical engineering at Washington University in St. Louis have developed a promising pathway to convert harmful nitric oxide, a key component of acid rain, into valuable nitric acid, which is used in everyday applications from fertilizer production to metal processing.
Feng Jiao, the Lauren and Lee Fixel Distinguished Professor in the McKelvey School of Engineering at WashU, and collaborators developed a method to convert nitric oxide (NO) emissions into high-purity, concentrated nitric acid (HNO₃). The new process operates at near-ambient conditions with minimal infrastructure, offering an economically viable solution to industrial nitrogen waste with economic and environmental benefits. The work was published April 3, 2025 in Nature Catalysis.
“We’ve developed an electrochemical approach to converting NO, a toxic waste gas, into valuable nitric acid,” Jiao said. “Our primary motivation is to address NO waste gases from mining sites, where large amounts of nitric acid are used to dissolve metal ores, leading to significant emissions. Our technology enables on-site NO conversion back into nitric acid for immediate reuse, creating a more sustainable and circular process.”
Read more at Washington University in St. Louis
Photo Credit: herbert2512 via Pixabay
