抄録
Thermal reaction of copper (II) oxide-ammonium dihydrogenphosphate-urea mixtures was carried out in a stream of nitrogen gas to prepare cyclo-tetraphosphate. Addition of urea was not effective for the formation of cyclo-tetraphosphate. Instead, an appreciable amount of cyclo-octaphosphate was produced at 400°C and at the urea/CuO/NH4H2PO4 mixing molar ratio of 2/1/2 or 4/1/2. Sodium cyclo-octaphosphate heptahydrate, Na8P8O24·7H2O, was prepared from the thermal product of a mixture with the urea/CuO/NH4H2PO4 molar ratio of 2/1/2.
