DEF/NOx reduction

Reduce NOx emissions from diesel engines

Stamicarbon offers technology concepts to produce 32.5% urea-in-solution AdBlue® - often known as AUS32 or DEF (Diesel Exhaust Fluid) – for reducing NOx emissions in diesel engines. As a licensor of urea technology, Stamicarbon is in an ideal position to develop a state-of-the-art solution not only taking into account the current regulations but also anticipating future developments and requirements.

The Challenge

Although it seems easy to make such a solution without in-depth knowledge of the application it is used for, crucial and costly mistakes are easily made.

Stamicarbon has thoroughly investigated all the requirements, evaluated the options and designed a cost-effective solution for our customers ensuring, guaranteed, the highest quality product for now and in the future. 

The solution used for NOx reduction has to be virtually free from everything but urea, which proves to be a challenge as most urea contains a certain concentration of ammonia, biuret and formaldehyde. Thus, it cannot be made by simply diluting or dissolving urea in deionized water, as was thought originally. 

This is often out of the required specification, and as such, prone to either damage or foul the expensive catalyst used for NOx reduction. This is, however, not the only issue. The water added for dilution or formed while producing urea also contains an unwanted byproduct (corrosion or polymerization products) which is not acceptable for the market. 

Not every plant is directly suited to produce such a urea solution and as a result, investments may well be much higher than originally anticipated.


Our Solution

Stamicarbon's design will supply a reliable and high-quality solution for the long term with lifetime support. We offer an alternative solution for the production of AdBlue® directly from an aqueous urea solution from any urea plant. 

The solution enables the production of high-quality AdBlue® that conforms to ISO standard specifications. Stamicarbon can also provide related services, including:

  • Certificate consultancy service
  • Quality management from process design to production, storage and transport
  • Operator training for plant operation


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