Low-temperature NOx reduction using H2 in the exhaust gas of diesel engines

To meet current and future emission limits, low-temperature NOx reduction is a focal point for diesel engines. The SCR and NSK methods used so far sometimes exhibit insufficient NOx conversion due to low exhaust gas temperatures (100 – 200 °C), especially during urban driving conditions, posing a problem for current diesel passenger cars.

To expand NOx conversion towards lower temperatures, catalytic reduction using hydrogen as an additional DeNOx technology presents itself. Hydrogen can be electrolytically generated from AdBlue in the vehicle, complementing currently used SCR systems.

• Selection of promising H2-deNOx catalysts based on literature review
• Laboratory evaluation of the catalysts and optimization of the best catalyst in terms of conversion and selectivity
• Assessment and validation of the best catalyst under real gas conditions on the engine test bench
• Development of electrocatalytic H2 generation through electrolysis of AdBlue
• Development of a concept for integrating the entire system into the vehicle environment
• Overall evaluation regarding NOx conversion, secondary emissions, H2, and energy demand