To selection of low-wear anode coatings based on iridium, ruthenium, titanium and tantalum oxides for direct electrolysis of natural waters

Abstract

Selection of anode coatings to obtain low-concentration sodium hypochlorite by direct electrolysis of natural waters is considered. The corrosion resistance of anodes with different packing of ruthenium, iridium and tantalum oxides, as well as their characteristics have been determined: chlorine current output, cell voltage, dynamics of growth of active chlorine concentration in solution. It is shown that when tantalum is added to the OIRTA system composition, the solid solution system turns from the three-component one into the four-component one, which adds certain advantages to the metal oxide coating of the anode: increased anode service life, reduction of the specific packing of precious metal (cost reduction), reduction of energy costs, which allows to conclude that it is expedient to use an OIRTA-Ta coating.