APP(Ammonium polyphosphate) is an important phosphorus raw material for the development of water-soluble fertilizers with following advantages.

APP(Ammonium polyphosphate) is an important phosphorus raw material for the development of water-soluble fertilizers with following advantages.

(1) The phosphorus content is high, the pH value is near neutral, and the crop safety factor is high.

(2) High solubility, liquid fertilizer with high phosphorus content can be configured; low crystallization temperature, convenient production and use.

(3) It has a chelating effect on metal ions, which can prevent metal impurities from forming precipitation in the solution. Adding trace elements to liquid fertilizers is conducive to making high-concentration and high-quality liquid fertilizers. Phosphorus is not easily fixed by metal ions such as iron and calcium in the soil, but can form soluble complexes with ineffective trace elements in the soil and be absorbed and utilized by plants.

(4) Although it is not directly absorbed by plants in the soil, it can be slowly hydrolyzed into orthophosphate in the soil and then used by plants. It is a slow-dissolving long-acting fertilizer.

(5) It can be made into foliar fertilizer for foliar spraying of crops. As a fertilizer, polyphosphate can be applied at a rate 3 times higher than orthophosphate, but it will not burn the leaves. Its neutral solution can remain on the leaves for several days without being evaporated or salted out.