An improved method for the preparation of high-purity permanganate salts

A simple and easy preparative route to obtain highly pure permanganate salt s via aluminium and barium permanganate is described. Aluminium permanganat e is prepared by a known method from KMnO4 and excess Al-2(SO4)(3), then co nverted to barium per manganate by reaction with excess barium hydroxide. T he residual KMnO4 content is co-precipitated together with BaSO4 or adsorbe d on solid AI(OH)3 (which are formed in large amounts during synthesis). Th e excess Ba(OH)(2) is transformed into an insoluble precipitate during heat ing of the Ba(MnO4)(2) solution. Ammonium, zinc, cadmium, magnesium and nic kel permanganates were prepared in high purity from pure barium permanganat e and sulfate salts.