Fundamentals of Nitrophosphates

The basic (and simplified) acidulation reaction can be represented by the following reaction equations  

Dicalcium phosphate is insoluble in water but soluble in ammonium citrate solution and is therefore regarded as a source of available P2O5, at least in the United States. However, fertilizer specifications often require high water solubility, and this type of product is limited to 50% water solubility of the P2O5. 

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