Urea is one of the most widely used organic nitrogen compounds in the world. It plays a crucial role in plant growth, the development of chemical industries, and various industrial processes. 

1. What is Urea?

Urea, with the chemical formula CO(NH₂)₂, is an organic compound composed of carbon, nitrogen, oxygen, and hydrogen. It appears as a white crystalline solid with high purity and excellent water solubility. The nitrogen content is approximately 46% of the dry weight, making it highly valuable for chemical and industrial applications.

Key Characteristics of Urea:

• Chemical formula: CO(NH₂)₂
• Nitrogen content: 46% — the highest among common solid nitrogenous compounds
• Physical form: White crystalline solid
• Solubility: Highly soluble in water
• Common packaging: 50 kg polypropylene bags or bulk industrial shipments

2. Types of Urea Based on Form and Processing

In this section, we examine various forms of urea produced in the petrochemical industry in Iran and worldwide. Differences in particle size, physical form, and processing methods result in diverse performance and applications in agriculture and chemical industries. The main categories include Prilled Urea, Granular Urea, Coated Urea, and Uncoated Urea—each with its own advantages, characteristics, and application requirements.

2.1. Prilled Urea

Characteristics:

• Small spherical particles (~2 mm in diameter)
• Rapid dissolution in water, suitable for blending with other fertilizers
• Pure white appearance, free from visible impurities

Advantages:

• Even distribution across the field
• Fast nitrogen uptake by plants
• Suitable for direct application or preparation of nitrogen solutions

Producing Companies:

• Shiraz Petrochemical Company — the oldest urea producer in Iran, with over 50 years of experience and high domestic/export supply capacity
• Khorasan Petrochemical Company — active in Central Asian markets and the domestic market

2.2. Granular Urea

Characteristics:

• Larger particle size (3–4 mm) and higher density
• Greater resistance to moisture and caking

Advantages:

• Ideal for mechanical spreading using agricultural machinery
• Reduced fertilization frequency thanks to gradual nitrogen release
• Effective for heavy soils in low-rainfall areas

Producing Companies:

• Shiraz Petrochemical Co.
• Pardis Petrochemical Co.
• Kermanshah Petrochemical Co.
• Razi Petrochemical Co.
• Masjed Soleyman Petrochemical Industries
• Lordegan Urea Chemical Co.

2.3. Coated Urea

Processing:

Using sulfur or polymer coatings, nitrogen release can be controlled. This ensures slow release into the soil and minimizes losses due to leaching or volatilization.

Applications:

• Sensitive crops such as tea, rice, and vegetables
• Agriculture in high-rainfall areas or under heavy irrigation

Producing Companies:

• Shiraz Petrochemical Co.
• Kermanshah Petrochemical Co.
• Khorasan Petrochemical Co.

2.4. Uncoated Urea

Characteristics:

• No protective layer
• Rapid dissolution in water and immediate nitrogen release
• More cost-effective compared to coated types

Applications:

• Suitable for dry soils and quick nitrogen requirements
• Preparation of quick-application fertilizer solutions

3. Urea Market in Iran

Urea is traded both inside and outside the Iran Mercantile Exchange (IME). According to IME data, three types—Prilled Urea, Granular Urea, and Prilled Urea (without formaldehyde)—are offered in the domestic ring of the exchange.

In the first half of 1404 (2025), Khorasan Petrochemical Co. had the highest prilled urea sales volume at 11,850 tons, while Shiraz Petrochemical Co. led in granular urea sales with 16,430 tons.

In some production processes, formaldehyde solution is added to reduce dust formation or prevent particle agglomeration. While harmless for industrial use, it can create limitations or concerns in agriculture and food-related applications. Prilled Urea without formaldehyde is essentially standard urea with no added formaldehyde, maintaining pure CO(NH₂)₂ composition.

Notably, Khorasan Petrochemical Co. is the only supplier of prilled urea without formaldehyde in the domestic ring of the IME and sold 4,760 tons in the first half of 1404 (2025).

4. Conclusion

Urea, with its exceptional nutrient storage and delivery capacity, exists in multiple forms to meet diverse agricultural and industrial needs. From the fine, fast-dissolving prills to moisture-resistant granules, from coated versions with controlled release to the simple uncoated form, each type serves distinct purposes. The production diversity at major Iranian petrochemical complexes—such as Pardis, Shiraz, Kermanshah, Razi, and Khorasan—has positioned Iran prominently in the global market. Combined with high production capacity, this range of products is a strategic asset for the reliable supply of nitrogen in agriculture and chemical industries.