FIELD: catalytic decomposition of hypochlorite-ions which comprise in flow of liquid. SUBSTANCE: flow of liquid comprising hypochlorite-ions is contacted with layer of catalyst as particles. Said catalyst decomposes hypochlorite-ions while liberation of oxygen, catalyst being displaced at least in two consequently connected layers which are disposed in cascade with stand pipes; flow of liquid is fed opposite to flow of oxygen being liberated. Volume rate of liquid comprising hypochlorite-ions which flows through layer of catalyst is 0.1-10 h-1, temperature of the process is 10-90 C. EFFECT: improved efficiency of the method. 4 cl, 1 dwg, 2 tbl
