Mono Ammonium Phosphate

The process for manufacturing MAP is relatively simple. In a common method, a one-to-one ratio of ammonia (NH3) and phosphoric acid (H3PO4) is reacted and the resulting slurry of MAP is solidified in a granulator. The second method introduces the two starting materials in a pipe-cross reactor, where the reaction generates heat to evaporate water and solidify MAP. Other methods exist as well. An advantage of manufactured MAP is that lower-quality H3PO4 can be used compared with other P fertilizers often requiring a more pure grade of acid. The phosphorus pentoxide (P2O5) equivalent content of MAP varies from 48 to 61 percent, depending on the amount of impurity in the acid. The most common fertilizer composition is 11-52-0.No special precautions are needed with the use of MAP. The slight acidity associated with this fertilizer reduces the potential for NH3 loss to the air. MAP can be placed in close proximity to germinating seeds without concern for NH3 damage. However, MAP used in foliar spray or added to irrigation water, shouldn't be mixed with calcium or magnesium fertilizers.