Kinetics of the reduction of molecular oxygen from water by ultrafine copper in an ion-exchange matrix

The rate of the reduction of molecular oxygen from water with a low-capacity copper-containing electron-ion exchanger at various initial ionic forms, grain radii, and sizes of metal particles dispersed into pores. The applicability of the mixed-diffusion and diffusional-kinetic models incorporating a first-order irreversible reaction to describing the system under study was examined. The kinetic parameters of the system were determined within the framework of these models. It was found that the limiting stage of the process in the stationary mode is the internal diffusion of oxygen molecules to the redox sorbent particle. The increase in the rate of the absorption of oxygen by samples containing copper of higher dispersity was observed at the initial stage of the process and was likely associated with an increase in the surface area of the reactive interface.     

Tests of Pilot and Industrial Pilot Installations for Catching of Nitrogen Oxides with Water Condensation Aerosols

A pilot installation for catching of nitrogen oxides with water-condensation aerosols, with a throughput of 10 m³ h^?1, was tested. A shell-and-tube industrial pilot installation for catching of nitrogen oxides with water-condensation aerosols, with a throughput of 1800 m³ h^?1, was fabricated and tested.     

Electroreduction of molecular oxygen on dispersed copper in an ion-exchange matrix

Electrochemical reduction of molecular oxygen was studied on a [dispersed copper]-[macroporous KU-23 15/100S sulfocation exchanger with various metal concentrations] composite electrode. It was found that a high proton concentration in the ion-exchange matrix causes a decrease in the oxygen reaction overvoltage. The nanostructured state of copper particles causes stabilization of the intermediate product, i.e., hydrogen peroxide. Using the rotating disk electrode method, it was detected that the process is limited by external diffusion of oxygen to composite grains. The oxygen reaction is mostly concentrated on the grain surface and surface layers; oxygen is reduced in the bulk due to dispersed copper oxidation.