Preparation of alkali metal ferrates.

Alkali metal ferrates are produced by prepg. a mixt. contg. an alkali metal or alk. earth hypochlorite, an iron salt, and an alkali metal hydroxide; adding an inert matter in the form of solid particles to the mixt.; reacting the mixt. under agitation; cooling the reaction mixt. to 50-90°, and recovering alkali metal ferrate granules by screening. Preferably, the reactants are basic iron sulfate, calcium hypochlorite, and KOH. The inert matter consists of cryst. anhyd. potassium sulfate having a particle size of \textgreater 0.1 mm. The cooling is carried out by blowing cold and dry air through the reaction mixt. The produced ferrate can be used as water treatment agent