Potassium phosphates are excellent fertilizers because of
their very high phosphorus content. At present, most
potassium phosphates used in fertilizers are produced
from potassium hydroxide or carbonate, and various
phosphoric acids as per the following chemical reactions:
These phosphates are used in liquid fertilizers for
foliar application or other speciality uses. Their
advantages arise from their (a) high analysis, (b) low salt
index, (c) ability to produce clear fluid fertilizers which are high in potassium (K2O), (d) route to making
polyphosphates with a controlled solubility, (e) status of
being free from fluorine and chlorine, which makes them
well-suited for use on tobacco, potato and other crops
sensitive to excessive amounts of chloride ions, and ( f )
containing major nutrients like potassium and
phosphorus.
In addition, a potassium phosphate solution of 0-26-
27 grade has been produced from superphosphoric acid
and potassium hydroxide; it contains a mixture of ortho-,
pyro- and higher poly-phosphates.
