FIELD: chemistry.SUBSTANCE: invention relates to a method of producing a disinfectant, which includes converting a freshwater solution of NaCl into an anolyte in the anode chamber of a diaphragm cell and into a catholyte in the cathode chamber passing streams into the anode and cathode chambers in one direction from the bottom up obtaining a disinfectant with pH 2.5-5.5 from the NaCl solution entering the anode chamber directly from a mixer for mixing a NaCl concentrate with fresh water obtaining a disinfectant with pH 5.5-8.5 from the NaCl solution entering the anode chamber after treatment thereof in the cathode chamber changing the pH of the disinfectant in the ranges 2.5-5.5 and 5.5-8.5 by changing the ratio between the streams in the electrode chambers by changing the value of the catholyte stream into the external medium removing the disinfectant from the electrolysis cell having the required concentration of active chlorine. The method is characterised by that NaCl solution prepared only from a portion of fresh water used in producing the disinfectant is treated in the electrode chambers the remaining portion of fresh water is fed first into the inner space of a hollow cathode, and then into the mixer-top of the electrolysis cell, where it is mixed with the anolyte coming from the anode chamber, which enables to obtain a disinfectant with active chlorine concentration of up to 2 g/l and pH in the range of 2.5-8.5. The invention also relates to an apparatus for producing the disinfectant.EFFECT: use of the present invention reduces consumption of NaCl and electric power, as well as fresh water.6 cl, 1 dwg, 2 tblИзобретение относится к способу получения дезинфицирующего средства, включает преобразование пресноводного раствора NaCl в анолит в анодной камере диафрагменного электролизера и в католит в катодной камере, протекание потоков в анодной и катодной камерах в одном направлении снизу вверх, получение дезинфицирующего средства с рН 2,5-5,5 из раствора NaCl,
