Diammonium phosphate (DAP) – Properties, applications and safety
Diammonium phosphate (DAP) is an important technical additive used in a wide range of industrial applications. As a phosphate fertilizer, DAP is widely used in agriculture, but this substance also finds diverse applications in the food industry, cosmetics, and other areas. In this blog post, we take a closer look at the properties, applications, and safety aspects of diammonium phosphate.
What is Diammonium Phosphate (DAP)?
Diammonium phosphate, also known as DAP, is a crystalline solid produced from ammonia (NH3) and phosphoric acid (H3PO4). The chemical formula is (NH4)2HPO4. DAP is an important fertilizer in agriculture as it provides nitrogen and phosphorus in a readily available form.
In addition to its use as a fertilizer, diammonium phosphate is also used in other industries. For example, it is used as a fire retardant, emulsifier, buffer system, or acid regulator.
Properties of Diammonium Phosphate
Diammonium phosphate is a white, crystalline powder with high solubility in water. It has a slightly basic pH of about 8. DAP is thermally stable up to about 100°C, at higher temperatures it begins to decompose.
The most important physicochemical properties of diammonium phosphate include:
- Chemical formula: (NH4)2HPO4
- Molecular weight: 132.06 g/mol
- Melting point: 155°C
- Boiling point: Decomposition from approx. 100°C
- Solubility in water: 58 g/100 ml (20°C)
- pH (in solution): approx. 8
- Density: 1.62 g/cm³
These properties make DAP a versatile substance in industry.
Applications of Diammonium Phosphate
The main application of diammonium phosphate is certainly its use as a fertilizer in agriculture. As a nitrogen-phosphorus fertilizer, DAP provides important nutrients for plant growth. It is used in both conventional and organic farming.
In addition, diammonium phosphate is also used in numerous other areas:
Food industry
- Emulsifier and stabilizer in foods
- Acidity regulator in beverages
- Leavening agent in baked goods
Cosmetics and personal care
- Buffer system in shampoos, creams, and lotions
- Moisturizing ingredient in skincare products
Fire protection
- Flame retardant in wood, textiles, and plastics
- Component of fire extinguishing powders
Other applications
- Industrial cleaning agents
- Water treatment
- Flame retardant in building materials
- Catalyst in the chemical industry
The versatility of diammonium phosphate is thus demonstrated in the numerous application areas in industry and consumer products.
Safety and Handling of Diammonium Phosphate
As with all chemical substances, certain safety aspects must be observed with diammonium phosphate. Although DAP is generally classified as relatively harmless, some precautions should be taken:
Health hazards
- Diammonium phosphate is non-toxic during normal handling and use.
- Inhalation of dusts may cause respiratory tract irritation.
- Direct skin contact may cause irritation.
- If swallowed, it may cause gastrointestinal discomfort.
Fire hazard
- Diammonium phosphate itself is not flammable, but can release ammonia when heated.
- In combination with organic materials, there is a fire hazard.
Environmental aspects
- DAP is water-soluble and can contaminate water bodies if disposed of improperly.
- In agriculture, fertilization should be adjusted to actual needs to avoid over-fertilization.
The following measures are recommended for the safe handling of diammonium phosphate:
- Use of personal protective equipment such as gloves and respiratory protection when dust develops
- Storage in a cool, dry place protected from moisture
- Separate storage from combustible materials
- Proper disposal in accordance with applicable regulations
By observing these safety instructions, handling diammonium phosphate can be made safe.
Conclusion
Diammonium phosphate is a versatile technical additive used in numerous industrial sectors. As a fertilizer, emulsifier, fire retardant, and in other applications, DAP impresses with its specific properties.
Although some safety aspects must be considered when handling diammonium phosphate, overall the substance is classified as relatively harmless. With the right precautions, DAP can be used safely and efficiently in industrial processes.
