Preparation and crystallization of short-chain polyphosphates

The preparation of short-chain condensed phosphates of tri-, tetra-, hexa-, and octaphosphates was achieved by hydrolyzing cyclo-tri-, cyclo-tetra-, c yclo-hexa-, and cyclo-octaphosphates in a strongly basic solution and then precipitating the produced short-chain condensed phosphates from the soluti on. Triphosphate was precipitated by adding metal cations or alcohol into t he solution as a well crystallized compound and was stable at normal temper ature. The crystallization of tetra-, hexa-, and octaphosphates was not eas y. Metal salts of these oligophosphates were amorphous and were unstable at normal temperature. Guanidine tetraphosphate and ammonium hexaphosphate we re crystalline and stable at normal temperature.