Diesel Exhaust Fluid (DEF) – AUS 32
High-Purity Emission Reduction Solution for Diesel Engines
Diesel Exhaust Fluid (DEF), technically known as AUS 32, is a high-purity aqueous urea solution formulated for diesel engines equipped with Selective Catalytic Reduction (SCR) systems.
DEF helps reduce nitrogen oxide (NOx) emissions and supports compliance with applicable vehicle and machinery emission requirements. It consists of 32.5% high-purity urea and 67.5% deionized water and must meet the applicable quality requirements of ISO 22241.
When injected into the exhaust stream, DEF decomposes to produce ammonia. Inside the SCR catalyst, the ammonia reacts with nitrogen oxides and converts them primarily into nitrogen and water, helping reduce harmful exhaust emissions.
What Is Diesel Exhaust Fluid (DEF)?
Diesel Exhaust Fluid (DEF), also known technically as AUS 32, is an aqueous urea solution used in Selective Catalytic Reduction systems to reduce NOx emissions from compatible diesel engines.
In many markets, this type of product is sold under the AdBlue® trademark. AdBlue® is a registered trademark of the German Association of the Automotive Industry (VDA). DEF and AUS 32 are the generic terms used throughout this page.
Key Benefits of Diesel Exhaust Fluid
1. Reduces Harmful NOx Emissions
DEF works with SCR technology to reduce nitrogen oxide emissions from compatible diesel engines. It is widely used in trucks, buses, passenger vehicles, and other diesel-powered equipment fitted with SCR systems.
2. Supports Environmental Compliance
The use of compliant DEF helps SCR-equipped vehicles and machinery meet applicable emission requirements, including relevant Euro standards and other regional regulations.
3. Supports Efficient Engine Operation
SCR technology allows diesel engines to manage NOx emissions through exhaust after-treatment. Depending on the engine design and operating conditions, this may allow manufacturers to optimize combustion and engine performance without relying solely on internal emission-control measures.
4. Non-Flammable and Suitable for Safe Handling
DEF is a non-flammable, water-based solution. It should be handled, transported, and stored according to the manufacturer’s Safety Data Sheet and ISO 22241 recommendations to preserve product quality and ensure safe use.
5. Practical Emission-Control Solution
For compatible SCR-equipped engines, DEF provides an established method of reducing NOx emissions. Correct product quality, storage, and refilling are essential for reliable SCR operation and for avoiding damage caused by contamination.
How Diesel Exhaust Fluid Works in Diesel Engines
DEF is stored in a dedicated tank and is automatically injected into the exhaust stream while the engine is operating.
After injection:
- Water evaporates from the solution.
- Urea thermally decomposes and produces ammonia.
- The ammonia enters the SCR catalyst.
- The catalyst facilitates reactions that convert NOx primarily into nitrogen and water.
The vehicle or equipment operator should monitor the DEF level and follow the manufacturer’s maintenance instructions. Using contaminated, diluted, or incorrectly formulated fluid may affect SCR performance and damage system components.
Applications of Diesel Exhaust Fluid
1. Road Vehicles: DEF is used in compatible diesel-powered trucks, buses, passenger vehicles, and commercial fleets equipped with SCR emission-control systems.
2. Agricultural and Construction Machinery: Compatible tractors, harvesters, excavators, loaders, and other off-road machinery may use DEF as part of their SCR systems.
3. Marine Applications: Certain marine diesel engines equipped with compatible SCR technology use aqueous urea solutions to reduce NOx emissions. Product specifications and operating requirements may vary according to the engine and applicable marine standards.
4. Industrial Equipment: Some diesel generators, stationary engines, and industrial equipment fitted with SCR systems use DEF or another specified aqueous urea solution for exhaust after-treatment.
Why Source Diesel Exhaust Fluid Through Green Gubre Group?
Green Gubre Group is an international supplier and trading company. We do not manufacture Diesel Exhaust Fluid ourselves.
We source DEF / AUS 32 from qualified manufacturers according to customers’ technical, commercial, packaging, and destination requirements.
ISO 22241 Requirements
Product compliance depends on the selected manufacturer and shipment. Technical documentation, including the Technical Data Sheet, Safety Data Sheet, and Certificate of Analysis, should be reviewed and confirmed before contracting.
Bulk Supply
Bulk supply may be arranged subject to manufacturer availability, destination, minimum order quantity, logistics conditions, and commercial agreement.
Quality-Focused Sourcing
Our sourcing process focuses on selecting suitable manufacturers and confirming the required specifications and documentation for each transaction.
Storage and Handling
DEF quality can be affected by contamination, unsuitable materials, excessive heat, and improper storage.
Recommended precautions include:
- Store the product in clean and compatible tanks or containers.
- Prevent contact with fuels, oils, dust, and other chemicals.
- Use equipment and materials suitable for DEF.
- Keep containers closed when not in use.
- Follow the selected manufacturer’s SDS and storage instructions.
- Avoid prolonged exposure to extreme temperatures.
Environmental Role of Diesel Exhaust Fluid
DEF supports the reduction of NOx emissions from compatible diesel engines equipped with properly functioning SCR systems.
Reducing NOx emissions can contribute to improved air quality, particularly in areas with significant road transport, construction, agricultural, or industrial diesel activity. Actual emission performance depends on the vehicle or equipment design, operating conditions, maintenance, SCR system condition, and quality of the fluid used.
Conclusion
Diesel Exhaust Fluid, technically known as AUS 32, is an important exhaust after-treatment solution for modern diesel engines equipped with SCR technology.
When produced according to ISO 22241 requirements, stored correctly, and used in a compatible SCR system, DEF supports effective NOx reduction and compliance with applicable emission standards.
Green Gubre Group can source bulk DEF / AUS 32 from qualified manufacturers based on customer specifications, shipment requirements, and commercial availability.
Trademark Notice
AdBlue® is a registered trademark of the German Association of the Automotive Industry (VDA).
Green Gubre Group is not affiliated with or endorsed by VDA and does not manufacture, market, or sell products under the AdBlue® trademark. Green Gubre Group supplies generic Diesel Exhaust Fluid (DEF) / AUS 32 sourced from qualified manufacturers according to customer requirements.
