DEF - Diesel Exhaust Fluid)

About DEF - Diesel Exhaust Fluid)

Long Description

Diesel Exhaust Fluid (DEF) is a non-toxic, colorless, and odorless solution made from high-purity urea (32.5%) and deionized water (67.5%). It is used in modern diesel engines equipped with Selective Catalytic Reduction (SCR) systems to reduce harmful nitrogen oxide (NOx) emissions. DEF is stored in a separate tank and injected into the exhaust stream, where it helps convert pollutants into harmless nitrogen and water vapor.

Key Specifications

• Composition: 32.5% Urea + 67.5% Deionized Water
• Standard: ISO 22241
• Appearance: Clear liquid
• Odor: Odorless (may have slight ammonia smell)
• Freezing Point: -11C
• Density: ~1.09 g/cm at 20C
• pH Value: 9.010.0
• Toxicity: Non-toxic, non-flammable, non-hazardous
• Storage Life: Typically 12 years if stored properly

Applications

• Heavy-duty diesel trucks and buses
• Passenger diesel vehicles with SCR systems
• Construction and mining equipment
• Agricultural machinery (tractors, harvesters)
• Marine diesel engines
• Power generators using diesel engines

Function

DEF is injected into the exhaust gases before they pass through the SCR catalyst. Under high temperature:

1. DEF decomposes into ammonia (NH) and carbon dioxide (CO).
2. Ammonia reacts with nitrogen oxides (NOx).
3. This chemical reaction converts harmful NOx into:
   • Nitrogen (N)
   • Water vapor (HO)

Benefits

• Reduces Emissions: Cuts NOx emissions by up to 90%
• Environmental Compliance: Meets BS6, Euro 6, EPA emission norms
• Improves Air Quality: Reduces smog and pollution
• Fuel Efficiency: Enables optimized engine performance
• Engine Longevity: Cleaner exhaust system reduces wear
• Non-Hazardous: Safe to handle and store
• Regulatory Requirement: Mandatory for modern diesel vehicles with SCR