Preparation of manganese(III) phosphate
Fourteen grams of concentrated nitric acid are mixed with 42g of 85% phosphoric acid contained in an evaporating dish. Ninety milliliters of a 50% (by weight) solution of manganese(II) nitrate are stirred in, the dish is covered with a close-fitting watch glass and heated on the steam bath, preferably in the hood. The color of the solution soon changes to amethyst, and oxides of nitrogen are evolved. The olive-green product settles out on the bottom of the vessel and some of it adheres tenaciously to the sides of the dish. When considerable material has formed, the mixture is suction-filtered and washed carefully with two 20ml portions of water, allowing the washings to run into the mother liquor. The filtrate is further heated on the steam bath and the residue on the filter is rinsed with 20ml of acetone to facilitate drying. The reaction mixture is worked over three or four more times in this manner and finally evaporated to a heavy sludge which is treated as described to isolate more of the product. The material is dried in air. Total Yield = 65g (monohydrate) This yield is quantitative based on the phosphoric acid. The product should be acid-free; otherwise it must be washed with water and acetone until the rinsings are neutral to litmus.
Inorganic laboratory preparations, by G. G. Schlessinger, 86-87, 1962
MANGANESE(III) PHOSPHATE HYDRATE, 104663-56-1, ACMC-20akkf, AKOS025294012, RT-022901