- Enables higher NOx reduction activity and faster response at less than 200 degrees Celsius
- Provides superior thermal stability and improved storage capacity
- Does not rely on metal-promoted zeolites or vanadium
Researchers at the University of Central Florida and BASF Corporation have developed a selective catalytic reduction (SCR) technology that can efficiently remove nitrogen oxide (NOx) emissions at temperatures less than 200 degrees Celsius. Nitrogen oxides are major pollutants emitted from internal combustion engines. Examples include gasoline and diesel vehicles and stationary sources such as power plants or pumping stations that run on natural gas, oil or coal.
The new NH3-SCR catalysts provide a solution to existing zeolite-based catalysts that require higher temperatures to reduce NOx emissions. Methods for fabricating NH3-SCR catalysts are also simpler and use less costly materials. Environmentally friendly, the new catalysts are resistant to sulfur dioxide (S02) and other poisons like phosphate and alkali metals.
The NH3-SCR invention consists of a series of metal oxide-based catalyst compositions (non-vanadium, non-zeolite materials) that effectively reduce nitrogen oxide emissions in engine exhaust. Included are methods of preparing the compositions and applying their use with catalytic components and exhaust treatment systems. As an example, the compositions can include a reducible metal oxide support containing ceria and one or more transition metal oxides as a redox promotor. They also can include an acidic promotor such as an oxide of niobium, tungsten, silicon, molybdenum, or a combination.
Stage of Development
- Low-cost and easily scalable
- Allows the use of a wide range of materials for fabricating thermally stable catalysts
- Advantageous in closed-coupled SCR applications with a duel-urea injection system, where the first SCR catalyst handles low-temperature NOx controls, such as during a cold start
- Chemical refinery
- Catalyst supply
- Automotive emission control