AdBlue® is the registered trademark of the Verband der Automobilindustrie (VDA) for high purity aqueous urea solution (32.5%) for use in selective catalytic reduction systems (SCR) to reduce emissions from Diesel Vehicles.
The AdBlue® is stored in a separate tank on the vehicle and from there is dosed automatically into the exhaust gas, as required to the amount of Nitrous Oxides (NOx) being produced by the engine
Following the dosing, the exhaust gas and AdBlue® mixture passes through the SCR system where a chemical reaction takes place, converting the harmful NOx to harmless nitrogen and water which is dispersed from the end of the exhaust
AdBlue® is non-toxic and safe to handle. It is not a fuel or a fuel additive and should only be used in the dedicated tank in your vehicle. It is refilled in a similar way to refuelling diesel.
SCR technology is being adopted by most large scale car manufacturers for new diesel engine vehicles and is becoming more widely available in petrol stations and by oil suppliers.