AdBlue® is a colourless liquid used in the car’s ignition system (SCR) to reduce emissions of harmful substances from diesel engines. The Euro 4 exhaust emission standards came into force in Europe in 2005. This legislation requires a reduction in nitrogen oxide emissions from the current level of 5.0 to 3.5 g/k Wh. The Euro 5 standards that came into force in 2008 have reduced the permissible level even further to 2.0 g/k Wh. In order to meet the new standards, the main European vehicle manufacturers have agreed on the new SCR technology (Selective Catalytic Reduction).

This is how AdBlue® – a high-purity urea solution – was born as a reducing agent. SCR technology is already used in the new Euro 6 generation of heavy-duty and passenger vehicles. How does SCR work? With the SCR method, the high NOX emissions produced by the engine’s optimum combustion efficiency are treated with a catalytic converter. This process requires the addition of AdBlue®. A precisely defined volume of AdBlue® is sprayed from the nozzle into the exhaust stream, where it is first hydrolyzed and then causes the nitrogen oxides (NOX) to be converted into nitrogen (N) and water (H2O) in the catalytic converter. AdBlue® is the ideal way to exploit the potential of SCR technology and ensure compliance with EU legislation on exhaust emission levels.