The process of electrochemical deoxygenation of water in an open flow system using a high-capacity Cu(0)-containing nanocomposite based on a Lewatit K 2620(Na + ) ion-exchange matrix is theoretically substantiated and implemented. Functioning is ensured by the simultaneous reduction of oxygen by means of polarization by an external current and due to the oxidation of copper nanoparticles with the formation of solid-phase products. It is shown that in a multistage electrochemical block filled with a granular nanocomposite layer, the process reaches a steady state over time, the rate of which is controlled by the value of the polarizing current. A seven-stage electrochemical unit is capable of continuously deoxygenating water by 95–96%. An additional chemical block increases the level of water deoxygenation to 99.9% or more. Theoretical calculation shows that for a rather long period (~10 4 h) the residual oxygen content can be ~1–3 μg/L (ppb).

The behavior of copper ion-exchange composites with metal particles of various sizes and contents in the electroreduction of oxygen dissolved in water have been studied. The primary size effect is significant for samples with low metal capacity: the smaller the metal particle size, the higher the process rate. At the same time, for samples with high metal capacity, the process occurs at approximately the same rate on copper particles obtained using different reducing agents due to the comparable size. A secondary size effect is observed due to the collective interaction of metal particles. The size effect was taken into account along with the effect of the content of metal particles using the proposed nanosized complex, which represents the ratio of capacity and size. At the level of electronic conductivity percolation, the nanosized complex reaches the limiting value corresponding to the highest degree of development of the reaction surface, which makes it possible to increase the current to the maximum current capacity. The reduction of oxygen occurs along several routes: electroreduction on copper particles, mainly on the surface of nanocomposite grains; and autocatalytic chemical reaction with electroregenerated metal nanoparticles in the nanocomposite grains. The electroreduction of oxygen generally reaches an intense steady-state mode.

New metal-polymer nanocomposites for deep water deoxygenation have been obtained and studied. A macroand monoporous sulphocation exchanger with a nanometer pore size was used as the polymer matrix, and the metal was nanodispersed copper deposited in the pores of the matrix. A specific feature of the studied nanocomposites is their sodium ionic form, which eliminates the possibility of the formation of soluble copper oxidation products. The established linear dependence of the copper capacity on the number of cycles of ion-exchange saturation chemical deposition shows that the process of metal deposition into the pores of the matrix does not have significant obstacles during 10 cycles and contributes to the production of high-capacity samples. The high efficiency and duration of the life cycle of high-capacity copper ion exchanger nanocomposites have been shown. Experimental studies of water deoxygenation in column-type apparatus with a nanocomposite nozzle were confirmed by a theoretical analysis of the process dynamics. Experimental data and theoretical calculations showed the deep level of water deoxygenation had practically unchanged values of pH and electrical conductivity. Residual oxygen can be controlled and does not exceed 3 μg/l (ppb). The hygienic and economic substantiation of the expediency of using the obtained nanocomposites is provided. The necessity of using modern nanocomposite metal-polymer materials for deep water deoxygenation circulating in technological systems was analysed. When using this innovation, the metal components of the distribution facilities will be protected from corrosion and, therefore, the hygienic requirements for the water quality of centralised drinking water supply systems will be ensured. Deep chemical water deoxygenation using copper ion-exchange polymer nanocomposites in sodium form allows solving the problem of the corrosion resistance of metals, ensuring that water meets hygienic requirements on a large scale. The competitive advantage of the considered water deoxygenation system in comparison with the known systems is the rejection of the use of precious metals-catalysts (palladium, platinum), pure hydrogen, and complex design solutions. The proposed new nanocomposite installation for water deoxygenation is characterised by its ease of use and can be built into a filter system for water purification. SWOT analysis of the advantages and disadvantages of the proposed method of water deoxygenation showed that its main advantages are the high oxygen capacity of the nanocomposite, low residual oxygen content (3 ppb (μg/l)) in the water, and ease of operation of the deoxygenator. Calculations of the economic efficiency of the nanocomposite have been carried out. The breakeven point is reached when producing only ~100 l of nanocomposite and a volume of sales ~1,600,000 roubles, above which a profit can be obtained. The payback period for an investment of ~15,000,000 roubles is rather short and will not exceed 2 years.