Nitric Acid Production According to State-of-the-Art Technology
At Covestro, we are advancing more sustainable production through our newly commissioned NAUCI (Nitric Acid Unit Climate Initiative) project at our Baytown and Caojing sites. This technology can reduce greenhouse gas emissions from nitric acid units by up to 99%.
Having successfully operated this proven technology at our German production site since 2011, we have demonstrated our long-term dedication to innovative climate solutions. Our NAUCI initiative exemplifies our commitment to operational climate neutrality by 2035. By significantly reducing our Scope 1 emissions, this project demonstrates that environmental leadership and operational excellence go hand in hand. Every industrial process tells a story – and ours is about turning a climate challenge into an opportunity.
This isn't just another technology implementation – it's pioneering collaboration in action.
Nitric acid serves as a crucial raw material in the production of MDI (methylene diphenyl diisocyanate) and TDI (toluene diisocyanate), two essential isocyanate building blocks for polyurethane manufacturing. These materials enable diverse applications including mattresses, furniture, energy-efficient building insulation, and automotive seating.
Leveraging thyssenkrupp Uhde's proprietary EnviNOx technology, the EnviNOx system specifically addresses the most challenging emissions from nitric acid manufacturing: nitrous oxide (N₂O) and nitrogen oxides (NOx).
Every ton of emissions we eliminate brings us closer to operational climate neutrality while maintaining the production efficiency our customers depend on.
Want to dive deeper into the science? Curious about the technical details behind NAUCI's breakthrough results? Read on for the chemistry and engineering that make it possible.
Greenhouse Gas (GHG) Emissions refer to the release of gases into the atmosphere that enhance the greenhouse effect, contributing to global warming and climate change. Primary greenhouse gases include Carbon Dioxide (CO2), Methane (CH4) and Nitrous Oxides (N₂O, NOx).
Covestro produces nitric acid at sites in the US, Europe and China using catalytic ammonia oxidation as described by the Ostwald process. In this process, ammonia is converted to nitric oxide. After the combustion of ammonia, the nitrogen monoxide product gas is cooled and routed to absorption, where it is finally absorbed in water to form nitric acid. Covestro operates dual pressure plants that utilize technology sourced entirely from external providers.
Building on established Ostwald process principles from the early 1900s, modern equipment incorporates advanced technologies for enhanced performance and environmental optimization.
While 80% of global nitric acid production serves fertilizer manufacturing, 10% supports products from companies like Covestro. As the largest users, fertilizer manufacturers set industry standards for nitric acid processes. From these established standards, Covestro selects the best technology for production and tail gas abatement.
Implementing N₂O pyrolysis catalysts in industrial processes efficiently converts the greenhouse gas N₂O into substances such as nitrogen and water.
NAUCI represents exactly the pioneering innovation needed to achieve our climate neutrality goals and support our sustainable future strategy.
