148 results about "Pyrophosphoric acid" patented technology

Pyrophosphoric acid, also known as diphosphoric acid, is the inorganic compound with the formula H₄P₂O₇ or, more descriptively, [(HO)₂P(O)]₂O. Colorless and odorless, it is soluble in water, diethyl ether, and ethyl alcohol. The anhydrous acid crystallizes in two polymorphs, which melt at 54.3 °C and 71.5 °C. The compound is not particular useful, except that it is a component of polyphosphoric acid and the conjugate acid of the pyrophosphate anion. Anions, salts, and esters of pyrophosphoric acid are called pyrophosphates.