Abstract
Sodium hexaphosphate was made by hydrolyzing cyclo-hexaphosphate in a 10M sodium hydroxide solution at -7°C, neutralizing the solution with hydrochloric acid, sampling a hexaphosphate solution by column separation, and then adding methanol to the hexaphosphate solution. Ammonium hexaphosphate was prepared by dissolving sodium hexaphosphate in water, removing sodium ions by passing the solution through a cation exchange resin, and then adding ammonia water and ethanol to the resulting solution. Alkaline earth hexaphosphates were made by dissolving the sodium hexaphosphate in water, adding alkaline earth chlorides to the solution, and aging it for 1h at 0°C with stirring. Sodium and alkaline earth hexaphosphates were amorphous and unstable. They decomposed to phosphates with shorter chain lengths at room temperature. Ammonium hexaphosphate was crystalline and stable at room temperature.
