Urea

What Is Urea?

Urea (chemical formula: CO(NH₂)₂) is an organic compound composed of carbon, nitrogen, oxygen, and hydrogen. It is the most commonly used nitrogen fertilizer worldwide due to its high nitrogen content (46% N) and excellent cost-to-nitrogen ratio. Urea is a white, crystalline, and non-toxic solid that dissolves easily in water, making it ideal for use in both solid and liquid fertilizer applications.

In addition to agriculture, urea is also used in chemical industries, livestock feed, automotive systems (DEF/AdBlue), and resins.

Key Properties of Urea

Property Value
Chemical Formula CO(NH₂)₂
Nitrogen Content 46% by weight
Physical Form White crystalline solid
Solubility in Water Highly soluble
Odor Odorless
Biodegradability Readily biodegradable

Main Applications of Urea

🧪 1. Agriculture (Fertilizer Use)

  • Supplies plants with readily available nitrogen.

  • Can be applied directly to the soil, dissolved in fertigation systems, or sprayed on leaves.

  • Often used in blends (e.g., NPK fertilizers).

🚛 2. Automotive Industry (Diesel Exhaust Fluid – DEF/AdBlue)

  • Urea is dissolved in deionized water and sprayed into the exhaust system of diesel engines to reduce NOx emissions, converting them into harmless nitrogen and water.

🐄 3. Livestock Feed

  • Used as a non-protein nitrogen (NPN) supplement to improve microbial activity in the rumen of cattle and sheep.

🏭 4. Industrial Uses

  • Raw material in the production of:

    • Urea-formaldehyde resins

    • Melamine

    • Adhesives and glues

    • Explosives (like urea nitrate)

    • Plastic foams and textiles

Types of Urea Products

Type Description
Granular Urea Larger particle size; better for bulk handling and storage.
Prilled Urea Smaller particles; dissolves faster in water.
Technical Grade Urea Used in resins, glues, and chemical production.
Automotive Grade Urea (DEF) Highly pure; meets ISO 22241 for AdBlue/DEF use.

Advantages of Urea in Agriculture

  • ✅ High Nitrogen Concentration: Cost-effective delivery of N to plants.

  • ✅ Neutral pH: Compatible with most soils.

  • ✅ Versatile Use: Suitable for dry spreading, foliar sprays, or fertigation.

  • ✅ Blends Easily: Compatible with other fertilizers.

Handling and Storage

  • Store in dry, well-ventilated areas to prevent moisture absorption (urea is hygroscopic).

  • Avoid contamination with acidic or alkaline substances.

  • Packaging: 50 kg bags, jumbo bags (500–1000 kg), or bulk.

Environmental Considerations

  • Overuse or incorrect application can lead to nitrogen leaching, ammonia volatilization, or greenhouse gas emissions (N₂O).

  • Best practices include split application, soil incorporation, and use of urease inhibitors to minimize losses.

Conclusion

Urea remains the backbone of global nitrogen fertilizer usage, offering unmatched nitrogen content, flexibility, and affordability. With additional applications in industry, livestock, and emissions control, it is one of the most important and widely produced nitrogen-based chemicals in the world today.