Boron Phosphate

Boron Phosphate (BPO₄) is a white infusible powder.  As a source of Boron, it is used as a fertilizer in agriculture.  As a source of phosphate, it can be used to prepare metal phosphates by solid-state exchange reactions.  It is also used as a catalyst for dehydration reactions in organic synthesis and is being investigated for use in flame retardants.

Boron Phosphate, due to its poor water solubility, is an effective Boron fertilizer, outperforming borax, ulexite, and colemanite in toxicity studies as it is less harmful to seedlings. It also serves as a precursor for solid-state reactions at moderate temperatures, reacting with various metal compounds to form transition metal phosphates.

In organic chemistry, it is used as a catalyst for dehydration reactions, such as the conversion of 1,2-propanediol to propanol, showing superior catalytic activity and durability. Its high-temperature stability also makes it ideal for flame retardants, offering a low-cost, low-toxicity alternative to traditional options.

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