Monoammonium Phosphate(MAP)

1. Agricultural Planting Sector

• High-Concentration Compound Fertilizer: MAP is a core nitrogen-phosphorus binary fertilizer, containing approximately 12% nitrogen and 61% phosphorus (as P₂O₅). It is one of the water-soluble phosphate fertilizers with the highest phosphorus content, and its aqueous solution is weakly acidic, making it suitable for application in alkaline soils. It effectively improves soil pH and replenishes nitrogen and phosphorus nutrients. It can be used as a base fertilizer, top dressing, or foliar fertilizer, suitable for crops such as wheat, corn, rice, cotton, melons, and vegetables. It is particularly effective in meeting the phosphorus requirements of crops during the seedling and flowering/fruiting stages, promoting root development and grain plumpness. It can also be used in the cultivation of chlorine-sensitive crops such as tobacco and citrus.

• Raw materials for compound fertilizers and water-soluble fertilizers: MAP is a key raw material for the production of multi-element compound fertilizers and specialized water-soluble fertilizers. It can be compounded with urea, potassium sulfate, potassium chloride, etc., to create fertilizers with different nutrient ratios, suitable for different crops and soil fertilization programs. In hydroponic nutrient solutions, MAP can serve as a precise source of nitrogen and phosphorus nutrients, ensuring balanced nutrient absorption by crops.

• Seedling substrate component: In the production of seedling substrates and microbial fertilizers, MAP provides nitrogen and phosphorus nutrients to seedlings and functional strains, promoting robust seedling growth, rapid strain reproduction, and improving seedling survival rate and microbial fertilizer activity.

2. Firefighting field

• Core raw material for dry powder fire extinguishing agents: This is a distinctive industrial application of MAP. MAP is a major component (comprising over 80%) of ABC-type dry powder fire extinguishing agents. Its extinguishing principle is as follows: at high temperatures, the phosphoric acid and polyphosphoric acid produced by MAP decomposition form a flame-retardant char layer on the surface of the burning material, isolating it from oxygen. Simultaneously, the released ammonia gas dilutes flammable gases, interrupting the combustion chain reaction. It can effectively extinguish various types of fires, including solid, liquid, and gaseous fires, and is widely used in fire protection systems in buildings, mines, ships, and vehicles.

3. Industrial Production Field

• Water Treatment Agent: MAP can be used as a scale and corrosion inhibitor in circulating cooling water systems. Its phosphate ions can form stable complexes or slightly soluble precipitates with calcium and magnesium ions in the water, inhibiting scale formation. It can also adjust the pH value of the water, alleviating corrosion of metal pipes, making it particularly suitable for alkaline water treatment scenarios.

• Electroplating and Surface Treatment: In electroplating processes, MAP can be used as a buffer and complexing agent in nickel and zinc plating systems to stabilize the weakly acidic environment of the plating bath, prevent the hydrolysis and precipitation of metal ions, and improve the uniformity, gloss, and adhesion of the coating. It can also be used in metal surface phosphating to enhance the bonding between the metal substrate and the coating.

• Flame Retardant Materials: MAP can be used alone or in combination with ammonium polyphosphate, magnesium hydroxide, etc., to prepare intumescent flame retardants for flame-retardant modification of materials such as plastics, wood, paper, and coatings. The flame-retardant layer formed by the decomposition of MAP at high temperatures can block heat and oxygen, significantly improving the fire resistance of materials, and its environmental friendliness is superior to halogen-containing flame retardants.

• Optical and Electronic Materials: High-purity MAP crystals have excellent optical transmittance and nonlinear optical properties, and can be used to prepare special optical materials such as laser devices and optical sensors. In the electronics industry, MAP can be used as a flame-retardant encapsulation material for electronic components, improving the fire resistance reliability of equipment.

4. Pharmaceutical and Biological Fields

• Pharmaceutical Excipients: In pharmaceutical preparations, MAP can be used as a pH buffer to stabilize the acid-base environment of oral solutions and injections, extending their shelf life. Simultaneously, due to its nitrogen and phosphorus content, it can be used as an auxiliary ingredient in electrolyte supplements to regulate body fluid electrolyte balance.

• Biological Experimental Reagents: MAP is a common component in the preparation of phosphate buffer solutions. It can be combined with diammonium hydrogen phosphate to construct acidic buffer systems, maintaining acid-base stability in experiments such as enzymatic reactions, cell culture, and protein purification. It can also serve as a nitrogen and phosphorus nutrient source for microbial culture media, ensuring the growth and reproduction of strains and the smooth progress of experiments.

5. Other Special Applications

• Food Industry: Food-grade MAP can be used as a food additive, providing a phosphorus source for yeast in baked goods production, promoting dough fermentation, and improving the texture and taste of bread and biscuits. It can also be used as a nutritional fortifier in functional foods to supplement the nitrogen and phosphorus minerals needed by the human body.

• Ceramics and Refractory Materials: MAP can be used as a flux in ceramic production to improve the density and smoothness of ceramic products; in refractory materials, it can be used as a binder to enhance the high-temperature stability and mechanical strength of refractory bricks.