Boron phosphate is an inorganic compound with the chemical formula BPO4. The simplest way of producing it is the reaction of phosphoric acid and boric acid. It is a white infusible solid that evaporates above 1450 °C.[1]
Boron phosphate is synthesized from phosphoric acid and boric acid at a temperature range from 80 °C to 1200 °C. The relatively cold treatment produces a white amorphous powder, which is converted to a microcrystalline product when heated at about 1000 °C for 2 hours.[2]
The main reaction of the process is:
H3BO3 + H3PO4 → BPO4 + 3 H2O
New ways of synthesizing the compound have also been reported, such as hydrothermal and microwave synthesis.[3]
Due to the particular industrial interest of boron phosphate, other methods are used as well:
If obtained at pressure, the ordinary structure is isomorphous with the β-cristobalite, while subjecting it to high pressure is obtained a compound isomorphic with α-quartz.[4] The structure of AlPO4, berlinite, is isomorphous with α-quartz.[1]
It is used as a catalyst for dehydration and other reactions in organic synthesis. Also, it serves as a source of phosphates for exchange reactions in the solid state to obtain metal phosphates.[5]