Diesel Exhaust Fluid – Blue DEF

Diesel Exhaust Fluid (DEF), is a high-purity aqueous urea solution specifically manufactured for use in Selective Catalytic Reduction (SCR) systems fitted to modern diesel engines.

DEF consists of 32.5% high-purity automotive-grade urea and 67.5% demineralized water. When injected into the hot exhaust stream, it helps the SCR system convert harmful nitrogen oxides (NOx) into primarily nitrogen and water.

DEF is not a diesel fuel additive and must never be added directly to the diesel fuel tank. It is stored in a separate DEF tank and automatically metered into the exhaust system.

Urea Solution 32.5%

Product Description

Urea Solution 32.5% is a clear, homogeneous aqueous solution containing approximately 32.5% by weight urea dissolved in water. It provides a convenient liquid source of urea for industrial applications where accurate dosing, rapid mixing and elimination of solid-urea handling are desirable.

The product can be used in industrial chemical processing, NOx-control systems, process-water applications and other formulations requiring a controlled concentration of urea.

Chemical Name: Urea
Formula: CH₄N₂O
CAS No.: 57-13-6
Concentration: 32.5% w/w Urea

Typical Specifications

RXSOL product, Diesel Exhaust Fluid (DEF) is the safer product use requirements are met.

How Diesel Exhaust Fluid Works

DEF is injected into the exhaust upstream of the SCR catalyst. At elevated exhaust temperatures, the urea generates ammonia, which participates in catalytic reactions with NOx.

The SCR process converts a significant proportion of the nitrogen oxides into nitrogen and water vapour, enabling compatible diesel engines to meet stringent emission requirements.

Applications

Diesel Exhaust Fluid is intended for SCR-equipped diesel engines used in:

• Heavy-duty trucks

• Buses and coaches
• Commercial vehicles
• Construction equipment
• Mining equipment
• Agricultural machinery
• Diesel generators
• Industrial diesel engines
• Off-highway equipment
• Marine diesel applications equipped with compatible SCR systems

Key Benefits

• Designed for modern SCR emission-control systems

• Helps reduce NOx emissions
• Ready-to-use 32.5% urea solution
• Manufactured using high-purity urea and demineralized water
• Suitable for automatic DEF dosing systems
• Non-flammable
• Water-based
• Helps SCR-equipped engines maintain designed emissions performance

Quality is Critical

DEF should not be manufactured using ordinary fertilizer-grade urea simply because it has the same chemical name.

SCR systems contain sensitive dosing equipment and catalysts, so impurities such as calcium, magnesium, sodium, potassium, iron, copper, phosphate and other contaminants must be tightly controlled.

For a product marketed as automotive DEF/AUS 32, both the raw materials and finished product should comply with the relevant requirements of ISO 22241.

Applications

Urea Solution 32.5% may be used for:

• NOx reduction and emission-control systems
• Selective Non-Catalytic Reduction (SNCR) processes
• Suitable Selective Catalytic Reduction (SCR) systems designed for aqueous urea
• Industrial chemical manufacturing
• Process chemical formulations
• Nitrogen-source applications
• Industrial wastewater-treatment processes where urea is required as a nutrient
• Controlled liquid dosing systems

Dosage

NOx Reduction

Urea solutions can be used as a reagent in appropriately designed industrial NOx-control systems. Under controlled operating conditions, urea ultimately provides ammonia species that react with nitrogen oxides to form primarily nitrogen and water.

The correct concentration, injection rate, temperature window and atomization conditions depend on the specific SCR/SNCR system and equipment design.

Important: 32.5% urea solution should not be represented as AdBlue/DEF/AUS 32. Automotive DEF is a standardized 32.5% high-purity urea solution, whereas this product contains approximately 32.5% urea.
 

DEF 32.5% vs Urea Solution 40%

These are not interchangeable products.

A 40% industrial urea solution should not be filled into a vehicle's DEF tank unless the equipment manufacturer explicitly specifies that concentration.

Notes

Key Benefits

• Ready-to-use liquid urea source
• 32.5% active urea concentration
• Eliminates on-site dissolution of solid urea
• Easy pumping and metering
• Rapid mixing with aqueous systems
• Suitable for automated dosing
• Consistent concentration
• Useful for industrial NOx-control applications
• Convenient for bulk industrial operations

Precautions

Storage

Store in a clean, closed and compatible tank or container and protect from contamination and excessive temperature. Because concentrated urea solutions can crystallize at sufficiently low temperatures, storage and transfer conditions should be selected to keep the product fully liquid.

For emission-control applications, contamination by metals, oils, salts or other chemicals should be carefully avoided where reagent purity is critical.

Urea 40 Percent solution is used as Selective Supplement for Urea Agar Base Christensen or Urea broth Base. Bacterial decomposition of urea has been especially useful in distinguishing between members of Proteus group and other organisms.

Keywords

Storage & Handling

DEF should be stored in dedicated, clean and compatible equipment to prevent contamination. Suitable materials commonly include appropriate grades of stainless steel and compatible plastics, subject to ISO 22241 requirements.

Keep containers tightly closed and protect the product from contamination, excessive heat and prolonged adverse storage conditions.

Dedicated pumps, hoses, tanks and transfer equipment are strongly recommended because even small amounts of contamination can adversely affect DEF quality and SCR-system performance.

RXSOL Diesel Exhaust Fluid DEF 32.5% – AUS 32

“Diesel Exhaust Fluid DEF 32.5% (AUS 32)”