What is AdBlue?

What is AdBlue?

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AdBlue® is the registered trademark of AUS 32 (aqueous urea solution 32.5%). The copyright of AdBlue® belongs to German Association of the Automotive industry (VDA). The product consists of aqueous urea solution (32.5%) and demineralized water (67.5%) and it is used as an additional solution in diesel engines that have a selective catalytic reduction system (SCR).

Using the SCR system in diesel engines is necessary for observing the ecological Euro 4 and Euro 5 exhaust emission norms.

The SCR technology consists of spraying specific doses of reagent AdBlue to the exhaust emissions in the presence of a catalyst, vanadium pentoxide. This results in chemical reaction that turns the harmful nitrogen oxides (NOx emissions) into safe N2 and H2O.

The production of AdBlue is strictly regulated in order to assure the highest quality of the product from the production process till delivering it to the end customer. There are two production standards to determine the quality of AdBlue, DIN 70070 and ISO 22241. The European Chemical Industry Council (CEFIC) has developed the Quality Assurance Guidance Document (QAGD) in order to control the production, storage and supply of AdBlue. When working with AdBlue solution, special equipment must be used.

AdBlue solution is produced by the largest urea producers in Europe, such as Yara, SKWP, AMI, BASF, Ab Achema etc.
ISO standards for AdBlue solution
ISO 22241-1. AUS 32 (AdBlue) quality requirements
Determines the qualitative properties of AdBlue, which are necessary for the SCR systems of the vehicles. This is the most recent international standard. The present standard replaces the previous DIN 70070 standard.
ISO 22241-2. Test methods
Describes the testing methods that are used to determine the qualitative properties of AdBlue. This standard replaces the previous DIN 70071 standard.
ISO/DIS 22241-3. Handling, transportation and storing
Describes the way to handle AdBlue solution. The document is similar to the QAGD instruction of CEFIC.
ISO 22241-4. Refilling interface
Describes the elements related with the filling device. Technical requirements for aqueous urea solution (AUS 32) in vehicles according to ISO 22241-1.