[Some aspects of water electrolysis with the use of a solid polymer electrolyte].

Electrochemical process in cells with a solid polymer electrolyte is dependent on catalyst durability in harsh environments and catalyst sputtering technology to ensure efficient power consumption. Active polymer electrolytes will permit to reduce substantially non-productive layouts and design a cost-effective, compact and safe system generator of high-purity oxygen and hydrogen. The existing designs of combined oxide systems integrating rear-earth and earth metals with a structure of Ln3+x Me2+1-x CoO3 containing perofskites were shown to be active catalysts in cells with a solid polymer electrolyte, and the sputtering technology was proven to reduce non-productive layouts in 2 or 2.5 times.

[Improvement of organization of oxygen generation technology in a solid electrolyte electrochemical system]. / Usovershenstvovanie ogranizatsii tekhnologii generirovaniia kisloroda v élektrokhimicheskom ustroistve s tverdym élektrolitom.

Candidate methods for improving the electrochemical oxygen production by a solid-oxide electrolyte with the fluorite-type structure and oxide electrodes with the perofskite structure were analyzed. After consideration of mechanisms of oxygen-producing electrode reactions, physical-chemical properties of oxide materials and diagrams of states of substances used as an electrolyte and electrodes in solid-electrolyte systems, a qualitatively new approach to arraying an electrochemical cell with a solid oxide electrolyte and oxide electrodes was proposed.

[Method of predicting electrochemical parameters of electrodes in a liquid electrolyte oxygen regeneration system on the basis of factorial statistical analysis]. / Metod prognozirovaniia élektrokhimicheskikh svoistv oksidnykh élektrodov na osnove mnogofaktornogo statisticheskogo analiza dlia ustroistv regeneratsii kisloroda s zhidkim élektrolitom.

The proposed method of predicting electrochemical parameters of multicomponent oxide surfactant compositions with a perovskite structure utilizes the factorial statistical analysis. The method originated from results of experimental investigations of the effects of a variety of physical/chemical factors of the oxide crystal structure (effective radii, effective electrical resistance and total valence of ions, number of unbound d-electrons, ion fraction within the ion-valent admixture, relative deflection of ad-component radius) etc. Slope of the linear segment of polarized curve and anode potential in close-to-equilibrium conditions were chosen to be the criteria of the electrochemical activity of oxide compositions.

[Perspective oxide materials for anode of low-temperature electrochemical oxygen regeneration system]. / Perspektivnye oksidnye materialy dlia anodov nizkotemperaturnykh élektrokhimicheskikh ustroistv regeneratsii kisloroda.

The paper summarizes results of substantiating, selecting, developing, manufacturing and testing of oxidic multicomponent surface compositions with the perovskite structure on porous titanium matrixes proposed for use in anodes of low-temperature electrochemical systems with a liquid electrolyte. Electrochemical activity of 88 oxide layers was evaluated as a function of composition, concentration and temperature of the carbonate electrolyte, elementary content of oxidic composition, and physical/chemical characteristics of the crystal structure. It was shown that the electrode process can be controlled by changing components of the electrolyte or complexity of the multicomponent oxidic surface compositions.

[Thermodynamics of the state of a multicomponent CO2-CO-H2O-H2-N2 gas mixture in an electrolyzer with a solid electrolyte]. / Termodinamika sostoianiia mnogokomponentnoi gazovoi smesi CO2-CO-H2O-H2-N2 v élektrolizere s tverdym elektrolitom.

The thermodynamic state of the gas mixture CO2 = CO = H2O = H2 = N2 in the cathode space of the electrolyzer containing a solid electrolyte is investigated. Calculation of the thermodynamic state makes it possible to determine the theoretical voltage of decomposition and concentration of individual components of this mixture at the outlet of the electrolyzer or each electrolytic cell as applied to various modes of operation. Knowledge of these parameters is important to build a technological scheme of a gas mixture regeneration system. Equations of four independent reactions are used to describe thermodynamic equilibrium reactions are used to describe thermodynamic equilibrium of the gas mixture. Particular cases that occur, when one, two or more conditions of the technological process are not satisfied, are considered.

[Derivation of the working equations of a CO2-CO-H2O-H2-N2 gas mixture for the cathode space of an electrolyzer with solid electrolyte taking into account its oxygen extraction]. / Vyvod rabochikh uravnenii gazovoi smesi CO2-CO-H2O-H2-N2 dlia katodnogo prostranstva élektrolizera s tverdym élektrolitom s uchetom izvlecheniia iz nee kisloroda.

Equations of thermodynamic equilibrium of the gas mixture CO2-CO--H2O-H2--N2 for the cathode space of the electrolyzer containing a solid electrolyte with extracted oxygen taken into consideration were derived. Equilibrium partial gas pressures, thermal effect of reactions, theoretical voltage of dissociation (the system of equations included 11 unknown parameters) were determined. These parameters are functions of temperature, total pressure of the gas mixture, initial gas composition, and the coefficient characterizing the degree of oxygen transfer from the cathode cell to the anode cell of the electrolyzer.

[Experimental research on the process of decomposition of a CO2-CO-H2O-H2-N2 gas mixture in an electrolytic cell with a solid electrolyte]. / Eksperimental'nye issledovaniia protsessa razlozheniia gazovoi smesi CO2-CO-H2O-H2-N2 v élektroliznoi iacheike s tverdym élektrolitom.

The experimental investigation was carried out in an electrolytic cell having the form of a short tube and containing a solid electrolyte of the following composition 0.9 ZrO2-0.1 Y2O3. The concentration of the gaseous mixtures investigated [H/C]00 varied in the range 0.22 to 18.0. The cathode polarization of the cell with platinum electrodes was measured as a function of the composition of the gaseous mixture [H/C]00 and oxygen content [O/C + H]0 at the temperatures 800, 900 and 1000 degrees C. The measurements demonstrated that the cell cathode polarization decreased as the water concentration in the starting mixture increased. The dependence of the cell cathode polarization on the oxygen content had minima in a specific range of the values [O/C + H]0. The minimal narrowed and shifted towards lower rations of [O/C + H]0. Simultaneously, the cell cathode polarization decreased as the water content in the starting gaseous mixture increased (ratio of [H/C]00).