Preparation of hydroxylamine phosphate
21 g of hydroxylammonium chloride are dissolved in 20ml of water at 40°C and constantly stirred while 12g of 85% phosphoric acid are added in one portion. An ice-cold solution of 12g of sodium hydroxide in 40ml of water is rapidly added dropwise from a separatory funnel while stirring is maintained. To avoid decomposition during the addition of the alkali, the temperature should not rise above 70°C; if necessary, the reaction mixture should be temporarily cooled in cold water. When all of the sodium hydroxide has been added, the crystalline slurry is cooled to 15°C, suction-filtered, and washed carefully three times with 10-ml portions of ice water. The obtained hydroxylamine phosphate is dried in vacuo yielding 16-18 g of final product.
Inorganic laboratory preparations, by G. G. Schlessinger, 77-78, 1962
Hydroxylammonium phosphate, Hydroxylamine phosphate salt (3:1), HYDROXYLAMINEPHOSPHATE, 55485_ALDRICH, 342351_ALDRICH, 55485_FLUKA
Hydroxylamine phosphate, IUPAC: Hydroxylamine; Phosphoric Acid, CID11252585, 20845-01-6